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Anmeldungsdatum: 07.08.2004
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BeitragVerfasst am: Sa Dez 08, 2012 12:07:13 
Titel: Boeing 787 Dreamliner - Special Feature
Antworten mit Zitat

dachte, das wird doch eventuelle Einige von Euch interessieren..

"THE ELECTRIC AIRLINER"

"Boeingvolt" sozusagen...

wir haben doch auch im Cabin Air Thread ganz kurz mal angeschnitten, dass die 787 in vielen Bereichen ganz neue ( oder auch alte) Wege geht..

Boeing hat jetzt im November einige Fachzeitschriften nach Seattle eingeladen um das Ding mal ordentlich im Flug und am Boden unter die Lupe zu nehmen..

Ich verlinke ( und paste & copy) hier mal die Beiträge von Flight Intl und Aviation Week..

Kurzer Tip: Für die Interessierten um auch an das Link im Flight Intl zu gelangen empfiehlt sich eine registration im FG Club dort, ist free of charge und gibt Access zu immer sehr interessanten Features..

Zuerst mal der Bericht von Flight Intl.

Der Pilot Report wurde von einem B757 / B767 Airline Pilot verfasst, der aber in seinem Lebenslauf auch mal die Edwards Test Pilot School gemacht hat und massgeblich in seiner militärischen Karriere beim F-35 Testing auch dabei war...also ein doch sehr beachtlicher Background..

Zitat:


IN FOCUS: 787 Dreamliner flight test

Test pilot Paul Smith got behind production-standard controls in a 787 test aircraft for an evaluation flight of Boeing’s technologically ground-breaking Dreamliner

By: Paul Smith

Two years ago, Flight International was offered a preview of the Boeing 787’s flying qualities when Mike Gerzanics flew and reported on CAE’s full-flight 787 simulator. The day before my evaluation flight of the aircraft itself, I spent time in one of Boeing’s simulators, which would prepare me well for the real thing. The preview Dreamliner was flight-test aircraft ZA005 (N787FT), configured with General Electric GEnx-1B engines. The flightdeck was production representative, while the passenger cabin was configured for flight-test operations.

Aviation buffs the world over would agree that if it looks right it will probably fly right, and as I walked to the preview aircraft I was once again reminded of how pleasing the 787 is on the eye. The gentle sweep of the wings, the smooth composite surfaces and the unique noise-reducing engine nacelles paint the picture of a bird yearning to fly. Aesthetics aside, what makes the Dreamliner’s design so intriguing is how Boeing has balanced the needs of its three main constituencies: the paying passenger, the purchasing airline, and the operations and maintenance crew.

Boeing
ZA005 is powered by BEnx-1B engines

My experience in the Joint Strike Fighter programme taught me balancing requirements is the chief engineer’s main task. Boeing has successfully balanced these requirements in the Dreamliner by retaining sufficient commonality with its 777 line to keep pilots and mechanics happy, and by using composites and alternative aircraft systems to cut manufacturing and operating costs and improve dispatch reliability.

While changes affecting pilots might be considered evolutionary, systems design considerations are revolutionary, reducing the need for engine bleed air and hydraulic systems power by relying more on electrical power and the large-scale use of composites in the structure.

There are many reasons behind Boeing’s composite design, including significantly less touch labour in manufacturing and an overall lower gross weight, with corresponding cost savings. Another justification for a composite design was to improve passenger comfort. Boeing conducted a vigorous analysis early in the design process to determine exactly what causes passenger fatigue. Cabin altitude and humidity play a part, but even more important is the off-gassing of volatile organic compounds. We may enjoy the “new car” smell associated with these VOCs, but they are subtly nauseating. They even emanate from the luggage and personal affects brought onboard by passengers.

CALMING EFFECT
In addition to a cabin filter, the Dreamliner has a gaseous filtration system to further purify the air. The larger window design permitted by the composite structure creates a calming effect for passengers as it provides more horizon references to reduce flying stress. The smooth composite fuselage skin reduces cabin noise – a subtle stressor.

Boeing
The cockpit design allows for improved situational awareness

The fuselage shape provides greater room at the cabin edges. For this 193cm (6ft 4in) pilot, the increased cabin height gave an airy feel to the cabin. This extra volume also extended to the cockpit, where I could easily walk in and sit at the controls, without being a contortionist.
Other revolutionary design considerations are not so apparent to the passenger but become a major consideration to the operating airline and mechanics who keep it flying.

Electrical power production is much more efficient than conventional engine-driven accessories and the Dreamliner’s electrical system has six generators: two 250kVA ones on each engine and two 225kVA units on the auxiliary power unit. The engine generators combined are starter/generators.

One primary benefactor of this electrical vice hydraulic power is the electrically driven brake system. Brake-system health is continuously monitored and alerts are set as needed if malfunctions or failures occur.
Brake-wear measurements are periodically checked after gear extension and this information is communicated to maintenance for tracking and replacement planning. In terms of dispatch reliability, the aircraft can have up to 25% of the brakes inoperative on each side. During slow-speed braking, only half of the brakes are used: two of the four on each side.
This saves on brake life, since carbonfibre brake wear is a function more of the number of brake applications than of braking force. The system rotates which four brakes are working as the pilot performs each brake application. At any time, full braking capability is available if the pilot needs it. From my perspective, the braking effectiveness was adequate and, more importantly, easily controlled, preventing sudden stops which might disturb passengers.

As with the 777, the Boeing 787 has three hydraulic systems but they operate at 345bar (5,000lb/in2) versus the 777’s 207bar. The higher operating system pressure allows for a lighter and more compact system.
REDUCED WEIGHT

The electrical system powers typical pneumatically operated ones such as air-conditioning and pressurisation which, in conjunction with the electrically powered hydraulic system, results in a significant reduction in wasted engine horsepower. For extended operations, the electrical system also provides back-up power and it is protected by electronic circuit breakers, accessible via MFDs. Each circuit breaker status is depicted in an easy-to-understand format which mimics actual physical circuit breakers.
I accompanied Boeing test pilot Mike Bryan as he performed the pre-flight walk-around inspection. The pre-flight was perfunctory and not much different from that of any other transport aircraft.

MEET THE PILOT
When our test pilot Mike Gerzanics had his hopes of flying the Dreamliner dashed by a car accident, his long-time colleague Paul Smith volunteered to step into the breach.
Smith and Gerzanics attended US Air Force test pilot school together. While Gerzanics left the USAF to work as a test pilot for United Airlines, Smith continued his service, finishing his air force career as lead government X-35 test pilot and commander of the Joint Strike Fighter joint test force.
He now flies Boeing 757s and 767s for a US-based airline. Additionally, he has developed an aviation consultancy that ?specialises in pilot-vehicle interface issues.
Smith: adding the 787 to a dazzling array of types tested


Boeing

The preview aircraft was equipped with a trailing cone pitot-static system, reminding me this was not a passenger flight. The brake system was extremely clean – no flammable hydraulic fluid near hot brake stacks. There are no bleed-air holes in the leading-edge devices as the slats are electrically anti-iced. Powerful copper heating elements embedded in the composite make it a fully evaporate system. The only parts of the aircraft de-iced by more conventional bleed air are the engine nacelle inlet lips.
Boeing has been touting the 20% fuel savings the Dreamliner offers over legacy aircraft, and 787 vice-president and chief project engineer Mike Sinnett says about 40% of the fuel-efficiency improvement is down to the engines. The large diameter fan with its wide chord and wildly curved blades lend credence to this claim on a visceral level. Major design effort has also been spent in optimising engine nacelle aerodynamics, attaining laminar flow over most of the nacelle

Entering through door 1 Left, it was immediately obvious we were on board a test aircraft – instrumentation racks and water tanks filled the cabin area. For the first half of the three-hour flight I was seated at a flight-test station in the cabin, with a great view of cockpit repeaters, while also being able to monitor cockpit communications.
I looked on as another preview pilot flew a similar flight profile. I could see the flightdeck displays are well arranged, with the primary flight display in a prominent position. The engine display is unobtrusive and can be moved from one pilot’s display to the other.

PASSENGER PERSPECTIVE
A benefit to sitting in the back while another pilot flies a similar profile is gaining the perspective a passenger has during manoeuvring flight. It is evident when the flight-control system’s “normal” mode is engaged or disengaged. The system provides pitch compensation by utilising control surface commands to minimise pitch responses to thrust changes, configuration changes – gear, flap, speedbrake – turbulence, and turns up to 30° of bank.
The system essentially smoothes pilot inputs and effectively washes out the adverse yaw, with the resulting kick one occasionally feels when a pilot is a little more aggressive on the controls.

Boeing
Boeing test pilot Mike Bryan took Paul Smith on the pre-flight walk-around

We encountered no bumpy air, but the Dreamliner’s gust-suppression system is designed to alleviate those uncomfortable ups and downs a passenger might feel. It utilises symmetrical deflection of the flaperons and elevators to alleviate gust acceleration. This function is active only with the autopilot engaged in “altitude hold” or VNAV level flight modes. Lateral gust suppression improves ride quality and can reduce pilot workload on approach by automatic application of discrete yaw commands in response to lateral gusts and turbulence. Operation of vertical and lateral gust suppression does not result in control yoke or rudder-pedal movement.

After watching the full stop landing on runway 32R at Moses Lake’s Grant County International airport from the cabin, I took my place in the cockpit’s left seat while Bryan configured the flight-management system (FMS) for our take-off.
We used the onboard performance tool to calculate take-off data, information which must be verified by both pilots before loading into the FMS. Being a test aircraft, we were able to read the centre of gravity immediately off the instrumentation display mounted on the top of the mode-control panel.

BREAKAWAY THRUST
The long taxi back to the approach end of runway 32R provided ample opportunity to evaluate the nose-wheel steering. At our light weight, breakaway thrust was minimal and idle thrust resulted in a slight acceleration throughout the taxi. The tiller and rudder steering are well integrated and I was able to gently nudge the Dreamliner around the field.

Toe braking was intuitive. The head-up display (HUD) shows groundspeed, allowing me to manage deceleration rates and minimise disturbance in the cabin. Dialling down the range scale on the horizontal situation display (HSD) gives a detailed airfield schematic, greatly improving situational awareness on an unfamiliar airport. This feature should help prevent runway incursions, especially in low-visibility conditions. Bryan tells me Boeing is studying future improvements to the HSD and HUD to enhance safety regarding runway incursions and excursions.

Holding short of the runway, Bryan reminded me we were going to carry out a simulated engine failure by pulling the right thrust lever back at V1. After ensuring final checks were accomplished using the electronic checklist, I pulled on to the runway and began the rolling take-off.
Of particular note is the ground-roll guidance provided by the HUD for low-visibility take-offs. The cues give the pilot steering guidance when transitioning from visual to instrument conditions. This was extremely useful during the V1 cut. Bryan pulled the right engine to idle shortly after reaching V1.

While forewarned, the subsequent yaw was surprising. We purposefully left the moderate yawing motion in the flight-control logic to cue the pilot as to which engine had failed. A small rudder input stopped the drift and, once airborne, the flight-control system fully kicked-in to zero-out yawing forces.

With the gear retracted we continued the climb to level-off altitude. During the entire V1 cut, the aircraft was stable. The back-driven rudder pedals assured me the aircraft was making the right corrections and helped me smooth my bank-angle rates in a surreptitious way. When I flew the same take-off in the simulator, I asked the operator to dial in a 15kt (28km/h) right crosswind and fail the right engine. The crosswind effects made the take-off more critical and in the simulator, the take-off was remarkably easy to fly. I was unable to dial in the wind for the actual take-off at Moses Lake, but I did feel confident the simulator modelled the single-engine effects well.



Once safely airborne, Bryan advanced power on the right engine to terminate the exercise. At this point, with only a few minutes under my belt in the left seat, I felt at home.

The Dreamliner shares a common type rating with the 777 – Boeing proposes only a five-day differences course for 777 pilots. While I have no time in the 777, there are many similarities between the 757/767, which I currently fly, and the 787.

We left the landing gear extended to cool the wheels and brakes for the pattern work. I looked on as Bryan accomplished all the FMS work, such as loading approaches, setting speeds and frequencies. After completing the landing checklist, the item “speed brake” was annunciated, as we left them unarmed for the touch and go. Bryan acknowledged and overrode it to close out the checklist.

Levelling off on downwind at 3,000ft (900m), Bryan set me up for an instrument approach. In the legacy 767, a non-precision approach must be hand-built, in a fashion, to provide vertical guidance to stay on a constant descent path.

Levelling off at an intermediate altitude, a technique called “dive and drive” is no longer an appropriate way to fly a non-precision approach. The autopilot flight director system (AFDS) in the integrated approach navigation (IAN) mode takes available guidance and builds an approach with a common format.

The Dreamliner’s AFDS IAN mode allows the use of consistent procedures for all types of instrument approaches and provides vertical and lateral guidance. To the pilot, all approaches look like a precision approach. The IAN mode does not support automatic landings, however, and the pilot must disengage the autopilot and complete the landing manually.
I liked the vertical situation display on the lower portion of the HSD, which presented location on the vertical path and pointed to slow and configure in order to fly an efficient constant descent approach. Turning on to final fully configured and on the vertical path for the approach, I easily kept the aircraft on both the lateral and vertical path using the flightpath marker in the HUD.

The approach’s glidepath angle was referenced on the same display allowing me to visually ensure I was on the correct glidepath. Lining up the flightpath marker with the end of the runway kept me on glidepath.
More importantly, had I been in the weather and broken out at decision height, seeing the flightpath marker on the landing zone and at the right glidepath angle would have immediately confirmed I was in a safe position to continue the approach to landing.

Although the HUD is not certificated as a primary flight display, the large display provides excellent situational awareness while allowing the pilot to keep his eyes outside where the real threats are. Speed cues on the airspeed tape made airspeed control a snap. Particularly useful were the flight-mode annunciators showing the commanded flight modes in the HUD.

The next pattern was a planned single-engine approach to a single-engine missed approach. On downwind, with the right engine pulled back, the P-beta feature of the flight-control system once again seamlessly manipulated the rudder to keep co-ordinated flight, in spite of asymmetric thrust levels. This inherent capability of the flight-control system significantly reduces pilot workload. Additionally, the 787’s autothrottle can be engaged on the good engine alone, allowing for automated speed management even during a single-engine approach.

FUEL BALANCING
Cumulative time spent with the right engine pulled back resulted in a slight fuel imbalance. While on final, Bryan pulled up the fuel synoptic to confirm the imbalance. Pushing a button on the overhead enabled the auto fuel-balancing feature – no more putting the checklist between the thrust levers to remind me I was balancing fuel. Once balanced, the system repositioned the valves and secured the fuel-balancing procedure.
Throughout the single-engine approach the aircraft demonstrated well-behaved flying qualities, even when turning into the simulated dead engine. I could feel the back-driven rudder pedals comfortably reminding me the system was performing as desired.

Reaching minima, I pressed the thrust lever-mounted TOGA switch to initiate a go-around. The autothrottle smoothly increased power on the good engine, while the P-beta scheme of the flight-control system zeroed out the yawing moment. With positive climb rate, I asked Bryan to raise the gear and we retracted the flaps on schedule. The weather had closed in so Bryan co-ordinated with air traffic control to fly towards the Tatoosh waypoint.

Shortly after reaching FL200, we broke out into clear air. After obtaining a block of airspace, I set up for a couple of turns in the flight-control system’s “direct” mode. Control doub-lets in all three axes elicited an aircraft response similar to one I would expect in the 767 or 757. I could feel the tail kick out during the rudder doublet as well as during the bank doublet. With “normal” flight-control mode selected, aircraft response to doublets was not degraded but the associated tail kick was gone.
Next came a demonstration of the Dreamliner’s flight envelope protection features. Boeing incorporates active protections in all three axes as well as overspeed and stall protection. In the pitch axis, the Boeing 787 uses a scheme called C*u, a blended g rate and pitch rate command system. At high speeds, the control column commands a g rate, with neutral being 1g. At slow speed, the control column commands a desired pitch rate. For lateral-directional (roll-yaw) control, movement of the yoke and rudder pedals commands proportional displacement of the ailerons – plus roll spoilers – and rudder to achieve the desired roll rate and sideslip angle.
Control surface deflection is a function of aircraft speed and yoke/rudder input magnitude. On the ground with speed below 60kt, the rudder-pedal movement commands rudder deflection. Above 60kt, rudder-pedal movement commands a yaw rate.

Once airborne, rudder-pedal movement commands angle of sideslip. In a conventional-control aircraft, sideslip will generate a roll in the same direction as the pedal input: left rudder will cause the left wing to drop. Pilots expect some roll caused by yaw and the 787 exhibits this characteristic while airborne.

BANK ANGLE
At bank angles less than 35°, the aircraft will maintain the desired bank angle and pitch attitude with no additional aft yoke input required. If the pilot commands a larger bank angle and then releases the yoke, the aircraft will return to – and hold – an angle of bank (AoB) of less than 30°. To evaluate this feature, I established a 30° AoB and continued to overbank until reaching 45°, which activated an aural warning. When I released the yoke, the aircraft corrected back to about 25°.

Design of the Dreamliner’s flight-control laws in the lateral-directional (roll and yaw) axes significantly enhances flight safety. At bank angles of 35° AoB or less, it demonstrates neutral spiral stability.

That is, when roll inputs are released, the aircraft maintains the current bank angle. Above 35° AoB, releasing roll inputs causes the Dreamliner to roll to, and maintain less than, 30° AoB. This feature prevents the pilot from inadvertently entering a descending spiral after rolling into a bank.
More impressive is the system’s ability to provide this stability even with the adverse yaw caused by an inoperative – simulated in this instance – engine. As demonstrated during my flight, the features designed for the flight-control system will reduce pilot workload and chances for error during a demanding engine-out event.

In the simulator, I flew the Dreamliner to its speed extremes to test the overspeed and stall protection features. However, in the aircraft I was a little more conservative in my approach.

At maximum velocity, the trim reference speed is limited by inhibiting trim in the nose-down direction. To overcome this, the pilot must apply twice the normal forward column pressure.

Likewise, in a slow-speed condition the pitch-trim function is inhibited in the nose-up direction. The pilot must apply continuous aft column pressure at twice the normal force to maintain airspeed below the minimum -manoeuvring speed.

The autothrottle supports stall protection if armed but disconnected. If speed decreases to near stick-shaker activation, the autothrottle connects in “speed” mode and advances thrust to maintain minimum manoeuvring speed – approximately the top of the amber band – or the speed set in the mode-control-panel speed window, whichever is greater. Another good safety feature, especially at low speeds, is the automatic retraction of the speedbrakes when a thrust lever is advanced to about three quarters of the way to “firewall”.

The icing on the cake to this flight was the opportunity to fly a typical airline descent and approach back at Boeing Field – giving me the opportunity to see how the aircraft behaved in normal service.

Boeing
Test pilots Paul Smith (second left) and Mike Gerzanics (right) with

Having flown the ILS runway 13R approach in a 767 many times during my airline career, I felt familiar with the arrival. The FMS provided a good constant descent approach vertical navigation plan, which was disturbed by air traffic control’s command to fly heading 100° for spacing and then to maintain 170kt to the marker.

V-speeds presented in the HUD allowed me to stay “head’s out” and search for the numerous traffic calls from air traffic control as I sequenced the flaps for landing. Navigating off lateral path did not prevent me from flying an efficient approach as the displays provided excellent situational awareness and energy state planning tools.

At TOGAE – the final approach fix – we dropped flaps 30 and quickly slowed to final approach speed. Fortunately, I was easily able to stay on vertical path, but had I been high the Boeing 787’s auto-drag function would have provided essentially what US Navy Lockheed Martin F-35 pilots will use to land on a carrier – direct lift control.

I observed the auto-drag feature provide direct lift control during the simulation sortie I flew. In this condition, the ailerons are deflected upward and the two most outboard spoilers are raised with no corresponding yoke deflection.

Auto-drag is only active in a landing configuration with flaps 25 or 30 and the thrust levers at idle, effectively increasing descent rate while maintaining the desired reference approach speed. These control deflections are gradually washed out below 500ft above ground level so flare and touchdown are not adversely affected.

HUD SYMBOLOGY
The HUD gave me well-tuned directional guidance, which naturally dampened any excessive inputs from my hands. During the latter part of the approach to flare and landing, the flight-control system demonstrated its outstanding ability to alleviate excess motions during the slightly bumpy final approach.

Use of HUD symbology, including radar altitude and listening to the altitude call-outs, allowed me to smoothly round out for the flare manoeuvre.

I placed the flightpath marker at the end of the runway and the aircraft smoothly touched down. Workload during the approach was low, even given the busy traffic around Boeing Field and the need to interact with heavy traffic flow into Seattle-Tacoma International airport.

The large HSD put myself and Bryan in the loop with respect to the numerous traffic calls as well as the approach’s lateral and vertical paths. The key to a successful approach and landing is being stabilised at 1,000ft, and every system on the Dreamliner worked to make my final landing a smooth one.

Many decisions factor into fielding a safe and cost-efficient aircraft, and a manufacturer must balance the requirements of the owners, travelling public and operators. My flight experience in the 787 demonstrated to me the commitment Boeing has made to satisfy those three main constituencies.

Obviously, the composite design and more electric system architecture will benefit the airlines from in-service rate and maintenance cost standpoints. Likewise, the improved comfort inherent in the Dreamliner’s larger, quieter and cleaner cabin will cause passengers to select it over legacy aircraft when given a choice.

At the business end, up front in the cockpit, the improved fly-by-wire flight-control system, larger, better-designed displays, and more intuitive systems management promote improved situational awareness and crew resource management. Pilots transitioning to the Dreamliner will no doubt quickly embrace the new technology to decrease workload and increase safety.

The Boeing 787 Dreamliner should offer improved dispatch reliability and operating cost performance, while enhancing passenger experience and the airline’s bottom line. However, perhaps a more important observation – at least from this pilot’s perspective – is that the Dreamliner is truly a dream to fly.


http://www.flightglobal.com/fg-club/in-focus/787-flight-test/flight-test/

Hier nun der Bericht including Pics und Video von Aviation Week. Der Fred George der hier fliegt, den kenn ich, der hat eher einen Bizjet Background, wenn ich mich richtig erinnere.

Sein Background:



Zitat:


Fred George Seattle

Background:

Fred is a senior editor with Business & Commercial Aviation. Fred is Aviation Week's aircraft evaluation specialist, having flown left seat in virtually every turbine-powered business jet produced in the past two decades. He has flown more than 150 individual aircraft types, ranging from the Piper J-3 Cub through Boeing and Airbus single-aisle jetliners, logging more than 5,700 hours of flight time. He has earned an Airline Transport Pilot certificate and four jet aircraft type ratings, and he remains an active pilot. Fred also specializes in avionics, aircraft systems and pilot technique reports. Prior to joining Aviation Week, he was an FAA designated pilot examiner [CE-500], instrument flight instructor and jet charter pilot. He also is former U.S. Naval Aviator who made three cruises to the western Pacific while flying the McDonnell-Douglas F-4J Phantom II. Fred has won numerous aviation journalism awards and serves as a Director of the San Diego Air & Space Museum.

Pilots who strap into Boeing's new 787 most likely will conclude that it is the easiest to fly and most intuitive jetliner ever built by the Seattle-based manufacturer, based upon our findings during a demo flight in mid-November. Five large-format LCD screens have 40% more display area than those in the Boeing 777, making room for better graphics that improve situational awareness. Standard left- and right-side head-up displays, plus left- and right-side electronic flight bags, (EFB), among other features, provide both pilots an equal access to all technology features. Enhancements to the digital fly-by-wire (FBW) flight-control system, adapted from the system used on 777s, make the new aircraft even more docile to handle, resulting in broader safety margins.

While the 777 and 787 share a common pilot type rating because of similar cockpit layouts, systems designs and handling qualities, there are substantive differences between the two aircraft. The 787 is the first commercial jetliner to have a primarily composite airframe. It has a higher aspect ratio wing with a 5% better lift-to-drag ratio than the 777.

The 787's higher bypass-ratio engines do not suffer efficiency losses from constant extraction of bleed air. The aircraft has a nearly all-electric systems architecture, except for high-pressure hydraulics to power some heavy loads and engine bleed air that is used occasionally for nacelle inlet anti-ice protection. Cabin pressurization is higher, so both crews and passengers will experience less fatigue on long flights. And the aircraft's more aerodynamic nose and windscreens means there is less ambient noise in the cockpit.

Boeing 787 engineers took on large-scale technology risks in designing this aircraft. Their goals included a 20% reduction in fuel burn, a lighter weight airframe and 30% lower maintenance costs than the 767, the aircraft that the 787, aka the “Dreamliner,” will replace in the model lineup. Increased range, a boost of cruise speed by nearly 30 kt., and an overall more comfortable passenger cabin were also key goals.

Overcoming some of the major risks was part of what led to a three-year delay in the aircraft's initial entry into service. The joints between the center wing carry-through box and main wing structures proved to be too weak, thus requiring modifications. An electrical fire in one of the aft-mounted large motor controllers, caused by metal foreign object debris, grounded flight-test aircraft until those boxes could be redesigned and hardened against moisture and metal-shaving intrusion. Myriad problems with outside suppliers also caused program delays.

After the aircraft went into service in October 2011, other snags emerged. One General Electric GEnx turbofan developed cracks in its fan mid-shaft. A manufacturing flaw in the aft fuselage section caused delamination of the carbon-fiber plies, resulting in extensive rework of several aircraft.

Boeing claims those woes now are history. At present, dispatch reliability exceeds 99%. Having delivered 38 aircraft and satisfied that they had matured sufficiently, Boeing invited Aviation Week to fly the 787 for an evaluation in mid-November.

Composite construction enabled the manufacturer to design a relatively stiff 10:1 aspect ratio wing for better lift-to-drag performance. Cabin pressurization also could be higher without incurring a significant weight penalty. Outside suppliers build large subassemblies that are shipped to Boeing facilities at Everett, Wash., and North Charleston, S.C., where they are joined using mechanical fasteners. Compared with conventional aluminum airframes, assembling the composite structure requires much less hand labor.

The 787 relies heavily on electrical power for functions that were powered by bleed air or hydraulics aboard the 777. Engine start, pressurization, horizontal stab trim, airframe ice protection and wheel brakes, for instance, are electrically powered. Each engine has two 250-kva starter generators in contrast to the single 120-kva integrated-drive generators on each engine of the 777. In addition, the auxiliary power unit (APU) has two 225-kva starter generators, thus there is a total 1.45 megawatts of power available. Each of the six starter generators produces three-phase, 235-volt alternating current (VAC) power. The 787 is also the first civil aircraft to have lithium-ion main batteries.

The starter generators are direct drive, so AC frequency varies with engine speed from about 360-800 hz. Approximately 40 systems, such as the wing anti-ice heaters, main fuel pumps, horizontal stab trim, alternate flaps and cargo bay heaters, are designed to use 235-volt variable-frequency AC power. Much of the 235-VAC power, though, is converted into 115-VAC 400-hz. three-phase, 28-volt DC and ±270-volt DC for use by other electrical systems.

High-amperage ±270-volt large-motor controllers—essentially liquid-cooled transformer rectifiers—supply power to variable-speed motors for hydraulic pumps, cabin air compressors, engine and APU starting, center tank fuel pumps and the fuel tank nitrogen inerting system, among a dozen such loads.

A network of 17 remote power distribution units supply 115Vac and 28Vdc for lighting, wheel brakes, avionics, windshield and air data probe heat, engine igniters, and cabin/galley services. The power supplies also provide secondary and back-up power for the digital fly-by-wire flight-control system.

In the cockpit, the 787 has electronic (“virtual”) rather than physical circuit breakers. These are monitored and controlled by means of point-and-click commands on a circuit breaker schematic displayed on the engine-indicating and crew-alerting system.

All fuel is stored in wet main and center wing tanks that are flooded with nitrogen to inhibit fuel vapor combustion. There are dual-AC fuel-boost pumps in each wing tank and center fuel tank. If no AC power is available, a stand-alone DC boost pump in the left main fuel tank supplies fuel for APU starting. If a fuel imbalance develops, the flight crew can balance the load simply by pressing a “balance” button in the overhead panel.

The aircraft has been upgraded with a 5,000-psi hydraulic system that uses smaller lines and actuators, thereby saving weight. Similar to the 777, the new aircraft has left and right engine-driven pumps. But, the left, right and center system pumps have variable-speed DC motors rather than constant-speed AC motors. The center system has two high-voltage DC pumps rather than two AC and two on-demand, bleed-air-powered pumps.

Hydraulic power is used for virtually the same functions as aboard the 777, but the normal and alternate wheel brakes are 28Vdc-powered.

The 787's digital fly-by-wire flight-control system architecture is similar to the 777 and it uses the same C*U (pronounced “Sea Star U”) pitch control law. C* means that fore/aft yoke movement commands pitch rate on the ground, and g rate or vertical acceleration (Nz) in the air. U means that speed stability is built into the control laws, so the pilot has to manually trim pitch in flight with speed changes.

A number of new FBW enhancements are on the 787. Roll control now is fully fly-by-wire. There is a “P-beta” yaw and roll asymmetry compensation function that uses inertial inputs from the Earth reference systems to counter weathervaning during crosswind takeoffs and landings plus thrust asymmetry during an engine failure.

Maneuver load alleviation progressively extends the outboard spoilers during high-g conditions to reduce wing-bending stress. Gust load alleviation also extends the spoilers and deflects the ailerons to reduce wing-bending in turbulence with the autopilot engaged. Autodrag helps the flight crew descend from above to capture glideslope/glidepath while maintaining airspeed at idle thrust by deflecting the ailerons downward and outboard two spoilers upward if the landing gear are extended and flaps are set to 25 or 30 deg.

Tail-strike protection decreases the risk of ground contact during takeoff and landing by decreasing elevator deflection. The cruise-flaps function automatically adjusts the flap, aileron, flaperon and spoiler positions at Mach 0.54-0.87 above flight level (FL) 250 to optimize wing camber for cruise efficiency.

When boarding the aircraft, I noted that the L1 main entry door is located relatively close to the left angle-of-attack (AOA) vane. Airlines are advised to train ground crews carefully in how to position the passenger boarding bridge to avoid damaging the AOA vane.

I strapped into the left seat of ZA005, the fifth flight-test article, with Capt. Mike Bryan, assistant chief 787 pilot, in the right seat as instructor and Heather Ross, 787 engineering project pilot, riding along in a jumpseat as safety pilot.

We used 115Vac ground power to supply the avionics and systems prior to APU start. Notably, ground electrical power can be used to supply the cabin pressurization pumps and thus air-condition packs. With at least two ground power sources, preferably three, the main engines also can be started on ground electrical power. However, airline operators say that the aircraft is sensitive about the quality of ground power, so voltage, frequency or amperage variability may affect aircraft electrical system performance.

Bryan explained that Boeing FBW aircraft have back-driven and interconnected yokes and rudder pedals, along with back-driven throttles and speed brake handles, that provide visual and tactile cues of what is going on in the cockpit. This is in contrast to some FBW aircraft fitted with side-stick controls that are not interconnected or back-driven and auto-throttle systems that do not move the thrust levers. It is more difficult in such cockpits to keep all flight crewmembers in the situational awareness loop, Boeing engineers assert.

But, Bryan also says that, unlike the 777, the 787 has no dedicated control display units for the flight-management computers (FMC). Multifunction keyboards on the center console are used to enter characters in the scratchpad field of a virtual control-and-display-unit (CDU) graphic on any one of three display screens. The scratchpad contents then are transferred into selected fields using a touch pad cursor control device. Without dedicated FMC CDUs, I would prefer a touchscreen user interface in place of the cursor control device entry method.

Using the virtual CDU, Bryan typed and clicked in our flight plan from Seattle-based King County International Airport/Boeing-King Field to Moses Lake-Grant County (Wash.) International Airport. He also used the interactive electronic checklist to run through pre-start checks. The system automatically checks off items when it senses that they have been completed.

We used the onboard performance tool software, hosted by the fully integrated electronic flight bags, to compute optimum slat/flap settings and V speeds for takeoff. Runway 13R was the active at Boeing-King Field. The temperature was 4C (39.2F) and the altimeter setting was 29.92. Based on a 350,000-lb. (158,757-kg) takeoff weight, the EFB recommended using slats/flaps 5 deg. It computed the V1 takeoff decision speed at 132 KIAS, 136 KIAS for rotation and 148 KIAS for the one-engine-inoperative takeoff safety speed. At the touch of a button, the EFB sends these data to the FMC and avionics system for indications on the primary flight displays.

After I started the APU, we used it to supply electrical power to start both main GEnx-1B70 engines simultaneously. A glance up at the overhead panel confirmed that knobs at 12 o'clock, and annunciator lights out, signified no problems. The electronic engine controls [full authority digital engine controls] handled all start functions.

It took very little thrust to move out of the chocks because the aircraft only was loaded to 70% of maximum ramp. Braking action was smooth and the tiller-controlled nosewheel steering precise. The rudder pedals command up to 8 deg. and the left and right tillers command up to 70 deg. of nosewheel steering.

Aligning the aircraft on Runway 13R, we pushed up the thrust levers midway, waited for the engines to stabilize at 40% N1 fan speed and engaged the auto-throttles. N1 stabilized at 94% as the engines produced their full 70,000-lb./takeoff thrust rating. With a 1:2.5 thrust-to-weight ratio, the lightly loaded aircraft had rather sporty acceleration.

Light back pressure on the yoke produced crisp but smooth pitch response. I followed the flight director cue in the head-up display to hold 10 deg. nose up. The test card called for me to engage the autopilot after retracting the gear and flaps. But, I elected to fly the aircraft by hand, using the HUD as the primary flight reference, for almost all my time in the left seat in order to evaluate the aircraft's handling qualities to the fullest.

Trimming for changes in airspeed takes just one touch of the trim switch to reset the trim reference airspeed. This does not directly move the horizontal stabilizer. Rather, the FBW system initially moves the elevators to change the trim and then follows up with stab trim to minimize trim drag. The control yoke does not change position with trim actuation.

Roll control, fully managed by the primary flight control computers, was silky smooth and nicely responsive, but not overly so. The FBW system provides artificial spiral stability up to 35 deg. of bank. There are no hard bank limits, so the aircraft can be rolled much steeper. But when the yoke is released, the FBW system forces the control wheel in the opposite direction to reduce bank angle to 30 deg.

Bryan also demonstrated how the P-beta function prevents thrust asymmetry or other uncommanded event from upsetting the aircraft in roll or yaw. In a stable 30-deg. bank angle, he retarded one throttle and advanced the other. The thrust asymmetry produced only the slightest change in yaw and virtually no change in roll angle. He repeated the process by reversing each throttle position. The result was the same. No upset, but enough seat-of-the-pants feel to detect the thrust asymmetry.

It is extremely unlikely that flight crews would ever experience a failure of the primary flight control computers that could cause the aircraft to be uncontrollable, but the engineers installed a switch in the overhead panel that allows pilots to disable the computers if they malfunction. Bryan then switched off the primary flight control computers so we could fly the aircraft using direct law. This enables the yoke and rudder pedals directly to command the positioning of the flight-control surfaces. The aircraft is completely controllable, but control response is comparatively crude and there are no flight envelope protections available.

The 787 also has protection against pitot/static system failure, such as an icing blockage. Switching to alternate air data enables the aircraft to compute airspeed and altitude from aircraft weight, configuration, AOA and 3-D GPS position. Using alternate air data, Bryan noted only a 8-9-kt. difference in airspeed and a 40-ft. variance in altitude while cruising at 300 KIAS and 16,000 ft.

We then proceeded to Moses Lake-Grant County for pattern work. We deliberately stayed high prior to descending for the instrument landing system (ILS) approach to Runway 32 so Bryan could demonstrate the aircraft's new autodrag function. The aircraft is so clean that it is difficult to descend to and capture glideslope or glidepath from above, even with gear down, flaps set to 25 or 30 deg. and idle thrust. Under these conditions, the autodrag function deflects the ailerons downward and two outermost spoilers on each wing upward to assist in descending without gaining airspeed. The function is phased out gently below 500 ft. above ground level so that normal flare and landing behavior is not affected.

Our first approach was a normal, all-engine, full 30-deg. flap maneuver that was hand-flown using the HUD and auto-throttles. Aircraft weight was 340,300 lb. Bryan bugged the target airspeed at 142 kt., 5 kt. above Vref. The aircraft was very stable, yet responsive to control inputs. It was easy to stay on localizer and glideslope via the HUD's precision guidance. Over the touchdown zone and 30 ft. above the runway, we flared slightly and touched down gently.

Bryan retracted the flaps to 5 deg., adjusted pitch trim and we advanced thrust for the go-around. On the downwind leg, he pulled back the right throttle to idle to simulate an engine failure. The P-Beta function stabilized the aircraft in yaw and roll. The left auto throttle adjusted the thrust as needed.

Based on a landing weight of 339,600 lb. and using Flaps 20 deg., Bryan set 146 KIAS as the target speed. The left auto throttle maintained that speed within 1-2 kt.

At ILS minimums, we executed a go-around. Bryan instructed me to leave my feet on the floor and allow the P-Beta system to counter the thrust asymmetry. The aircraft lost none of its composure during the maneuver, but there was noticeable side slip to the right caused by the left engine's higher thrust output.

We continued the simulated one-engine-inoperative abnormality for our final landing at Moses Lake. Using Flaps 20 deg. and based on a landing weight of 337,600 lb., Vref was 140 KIAS and the target airspeed was 145 KIAS.

Touchdown was smooth, but I floated a little too long in ground effect. I relaxed prematurely. Make a note. You must fly the nosewheel down to the runway, or you can be embarrassed by an audible thump during the derotation.

The 787 is indeed the nicest handling and most docile handling Boeing jetliner I've yet flown. Enhancements to the company's FBW flight-control system increase safety margins and make the aircraft impressively pleasant to hand fly.

The aircraft can be flown with equal ability from either seat because the left and right sides have the same access to displays, controls and tools, including left and right HUDs, EFBs and steering tillers. Situational awareness and crew resource management are top notch because of the moving and interconnected control yokes and rudder pedals, along with the back-driven throttles and speed brake handle.

Admittedly, the aircraft entered service three years later than planned. But, judging on performance, it was worth the wait.

Fly along with Aviation Week Editor Fred George as he tries out the 787's advanced features: watch a brief video of his flight in the digital edition of AW&ST on leading tablets and smartphones, or view the full-length video on the 787 Pilot Report Special Topic page at AviationWeek.com


http://www.aviationweek.com/Article.aspx?id=/article-xml/AW_12_10_2012_p46-522072.xml&p=1

http://www.aviationweek.com/Blogs.aspx?plckPostId=Blog:7a78f54e-b3dd-4fa6-ae6e-dff2ffd7bdbbPost:903d666b-69d5-4679-a704-0d63a1968a95

http://www.aviationweek.com/Blogs.aspx?plckBlogId=Blog:7a78f54e-b3dd-4fa6-ae6e-dff2ffd7bdbb&plckPostId=Blog:7a78f54e-b3dd-4fa6-ae6e-dff2ffd7bdbbPost:5ec64a46-ec59-4e91-b1c7-e230a4d3462e

http://www.youtube.com/watch?v=-s9ynMnPdCQ&feature=player_embedded[/quote]
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BeitragVerfasst am: Mo Dez 10, 2012 21:10:28 
Titel: Evolution und/oder Revolution....
Antworten mit Zitat

das soll ja hier keine Werbeeinschaltung für den Dreamliner werden, interessant ist es aber doch, zu ergründen, was an dem Flieger als normaler Fortschritt gelten kann, und was man eigentlich als radikal neuen ich möcht fast sagen revolutionären Designapproach bezeichnen könnte...

was für Vorteile, aber auch Risken liegen darin..?

warum kann man doch den B 787 Dreamliner als "Electric Airplane" bezeichnen...

Die B-787 in general...

Gut, Composite Construction ist in dem Scale bei einem Airliner zwar auch neu, aber würde ich als evolutionär bezeichnen...

Die Fly-by-Wire control laws wurden gegenüber dem vorigen ( und ersten) zivilen Fly-by-Wire Modell von Boeing, der 777, verfeinert...auch evolutionär..

Cockpit, ist evolutionär, LCDs und in der Presentation mit dual HUDs und voll integrierten EFBs auch evolutionär..

Input von Daten ( Trackballs - und -pads), da hat man sich die Cockpit Revolution von Dassault beim Falcon EASy Cockpit abgeschaut, auch gut und tolle Sache.. also evolutionär..

General:



http://www.boeing.com/commercial/aeromagazine/articles/qtr_4_06/article_04_1.html

Jetzt wird es aber interessant...

Der "Electric Airplane" Teil...

das würde ich als revolutionär bezeichnen....

Zitat:
...The 787's no-bleed systems architecture will allow the airplane's engines to produce thrust more efficiently — all of the high-speed air produced by the engines goes to thrust. Pneumatic systems that divert high-speed air from the engines rob conventional airplanes of some thrust and increase the engine's fuel consumption.

Boeing believes that using electrical power is more efficient than engine-generated pneumatic power, and expects the new architecture to extract as much as 35 percent less power from the engines. Conventional pneumatic systems generally develop more power than is needed in most conditions, causing excess energy to be dumped overboard....


Hier sehr gut und genau erklärt...

http://www.boeing.com/commercial/aeromagazine/articles/qtr_4_07/article_02_1.html

Ist natürlich schon eine wilde Sache...

Das Baby hat insgesamt eine Electrical Power Generation von 1450 KVA ( inklusive der zwei Gennies auf der APU)......( klar Pressurization ist elektrisch, Wing Anti Ice ist elektrisch, Brakes etc etc...das braucht "Juice"...) nehm an, wenn man eine "electrical load analysis" einer typischen 787 sehen könnte, wenn da alles an ist von Wing Anti Ice zu den Öfen in den Galleys und jeder Bizclass Pax noch seinen Laptop am Sitzoutlet charged...naja, da werden schon loads von 700.000 Watt zusammen kommen...schätz ich mal

Also würde meinen, rechnen wir die available Generatorpower grob mit 0.8 um, das macht in etwa 1,2 Megawatt.....naja...vielleicht kann mir wer da helfen, lieg ich da richtig, dass da ne kleine Stadt mit sagen wir mal 5000 - 10000 Einwohnern schon ganz gut versorgt werden könnte...?

Massiven Kurzen möcht ich keinen haben in der 787....könnt interessant werden....da brutzelts..( wie eh auch bei einem Testflug damals geschehen, als eine Power Distribution Box in Flammen aufging, und ein Proto 787 ganz schnell landen gehen musste...ist gut gegangen..)

aber insgesamt natürlich eine wilde neue Sache.....

P.S.: Nur um das in eine Relation zu setzen, was Electrical Power Generation auf der 787 im Vergleich zu herkömmlichen Modellen bedeutet:

Nehmen wir eine in-flight condition, wo nur die Generators auf den Treibern laufen und die APU off ist:

B 787: 1000 KVA total ( 4 x 250 KVA)

B 767: 180 KVA total ( 2 x 90 KVA)

B 747-400: 360 KVA total ( 4 x 90 KVA)

A 380: 600 KVA ( 4 x 150 KVA)

Zur Abrundung hier noch ein Blick auf die neue Triebwerksgeneration die in der 787 verbaut wird..



http://www.boeing.com/commercial/aeromagazine/articles/2012_q3/2/

und ein kleiner Blick auf die Flight Deck Technologie

http://www.boeing.com/commercial/aeromagazine/articles/2012_q1/3/

Das Boeing AERO Magazine ist sehr nett aufbereitet und gibt gute state-of-the-art Information über viele Belange..

http://www.boeing.com/commercial/aeromagazine/articles/2012_q4/index.html

http://www.boeing.com/commercial/aeromagazine/archive.html


Zuletzt bearbeitet von Viper am Mo Dez 31, 2012 14:47:58, insgesamt einmal bearbeitet
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BeitragVerfasst am: Do Dez 13, 2012 11:19:18 
Titel: kleines Detail
Antworten mit Zitat

"Aviation Week" schätzt, dass die gesamte Elec Gen Power der 787 ausreicht um 400 Haushalte zu versorgen...

damit meinen die sicher US Haushalte..

wenn man jetzt in Rechnung stellt, dass europäische Haushalte doch weit energieeffizienter sind ,könnte man dann eventuell sagen, gut, das entspricht in etwa 1000 Haushalten bei uns, nehmen wir 3 Personen pro Haushalt...

naja dann hätten wir in etwa 3000 Personen versorgt mit der Energie..

Hat da wer Zahlen, könnte das in etwa stimmen?
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BeitragVerfasst am: Do Dez 13, 2012 17:05:39 
Titel: Re: kleines Detail
Antworten mit Zitat

Viper hat folgendes geschrieben:
Hat da wer Zahlen, könnte das in etwa stimmen?


Laut E-Control betrug der durchschnittliche Jahresverbrauch (2009) an elektrischer Energie pro österr. Haushalt 4.200 kW/h.
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BeitragVerfasst am: Do Dez 13, 2012 17:24:02 
Titel: Danke....
Antworten mit Zitat

wenn ich es richtig gerechnet hab, dann komm ich demnach bei uns im Vergleich dazu auf 2.400 Haushalte...

das könnt dann stimmen...

stimmt dann sicher auch im Verhältnis zu den 400 US homes, da die drüben in den USA ja auch hauptsächlich mit Strom heizen und Air Condition machen..

das fällt beim durchschnittlichen österreichischen Haushalt ja weg, weil man da mit Gas oder Öl heizt z.b, und keine Aircondition hat..
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BeitragVerfasst am: Mo Dez 17, 2012 16:00:44 
Titel:
Antworten mit Zitat

Dreamliner erstmals in Österreich:
http://noe.orf.at/news/stories/2563547/

Witzig: ein Schaulustiger aus Kärnten sagt aus "der Dreamliner ist ein hässliches Flugzeug"....hat der Mann schon einmal den 380 aus der Nähe gesehen? lol
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BeitragVerfasst am: Mo Dez 17, 2012 21:57:47 
Titel: naja.....
Antworten mit Zitat

ganz ehrlich, slightly off-topic...

wirklich schön und elegant sind ja die ganzen modernen wide-bodies alle nicht unbedingt...

die letzte jüngere Boeing, die meiner Meinung nach elegant ausschaut ist ein narrow - body die 757



http://www.boeing.com/companyoffices/gallery/images/commercial/757200-01.html

und dann gibts noch , meiner Meinung nach DEN Klassiker in Eleganz unter den Airlinern...

die Caravelle...



http://www.austrianwings.info/2010/05/55-jahre-caravelle/

könnte man in NYC im Museum of Modern Art ausstellen und alle weltbekannten Designer würden lange stehenbleiben und könnten sich nicht sattsehen...
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BeitragVerfasst am: Di Dez 18, 2012 12:03:56 
Titel: Austrian Wings
Antworten mit Zitat

haben da eine nette Story über den LOT 787 Besuch in Wien..

Die LOT dürfte in den nächsten Wochen mit der 787 "sector training" und "shake-down runs" auf Kurzstrecken in Europa machen bevor es dann auf der LOT "Ölspur", der gut ausgebuchten Langstrecke von Polen in die grösste polnische City in Nordamerika, nach Chicago, ORD, lostgeht...

nett so ein neuer Flieger...

http://www.austrianwings.info/2012/12/dreamliner-erstmals-am-flughafen-wien-gelandet/

und unser guter Georg Mader kommentiert die Sache in einem TV Bericht..

http://www.viennaairport.com/jart/prj3/va/main.jart?rel=de&content-id=1354638551875
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BeitragVerfasst am: Fr Jan 04, 2013 13:18:09 
Titel: 787 "teething troubles"
Antworten mit Zitat

naja, da kommt auf Boeing und die Supplier jetzt ganz schön Arbeit zu, um das Ding "wetterfest" und "wasserdicht" zu bekommen in Hinblick auf Dispatch Reliability...

nicht zufällig scheinen die Hauptprobleme derzeit mit Ausfällen von Komponenten in der neuen "elektrischen" Architektur des Fliegers zu liegen...

man wird sehen, wie schnell sich die Lage "beruhigt"



http://www.flightglobal.com/news/articles/lan-working-with-boeing-on-787-reliability-issues-380664/

http://www.flightglobal.com/news/articles/united-juggles-787-international-schedule-on-reliability-issues-380631/
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BeitragVerfasst am: Di Jan 08, 2013 08:48:13 
Titel: Li-Ion Batterie Feuer?
Antworten mit Zitat

war nur eine Frage der Zeit, dass sowas hier passiert auch bei der 787...

http://www.flightglobal.com/news/articles/boeing-working-with-jal-on-787-fire-at-boston-airport-380751/

http://www.boston.com/metrodesk/2013/01/07/boeing-dreamliner-reported-fire-logan-international-airport/1HCFhQuwAn8ELwuDg5oDgI/story.html

Vor eineinhalb halb Jahren bereits hat sich Cessna im wahrsten Sinne des Wortes verbrannt dabei, als sie ein neues Modell mit einer Li Ion Main Battery ausgestattet hatten...

als sie bei Nummer 35 in der Auslieferung waren, ist ihnen der eigene Demonstrator im Hangar in Wichita abgefackelt, als in dem Flugzeug die Li Ion Batt hochging..danach mussten auch auf Anweisung der Behörde alle bereits ausgelieferten Flugzeuge auf Ni Cads oder Lead Acids umgerüstet werden..

Hat mich auch gewundert erstens, dass Li Ions überhaupt zugelassen wurden, beim damaligen Entwicklungsstand dieser Batterietechnologie, und, dass sich Boeing traut das einzubauen....solange die Flieger am Boden abfackeln und niemandem was passiert, OK, aber was macht ein Long Range Flieger, der 1000 NM von einem möglichen enroute Alternate entfernt ist, wenn sich so ein Ding durch den Flieger schweisst..?
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BeitragVerfasst am: Di Jan 08, 2013 10:34:33 
Titel: das hier war
Antworten mit Zitat

im Jahr 2011 die Situation bei der Cessna C525C, kommerzieller Name, CJ 4

http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAD.nsf/0/1A1F5BFBC840987F8625793B00494EDD?OpenDocument

wenn ich mich recht erinnere war auch der Umbau auf konventionelle Batterietechnologie gar nicht so einfach und billig, wie in diesem FAA AD beschrieben..

Nickel Cadmium und Bleibatterien unterscheiden sich zwar auch im Lade- und Entladeverhalten voneinander, aber die neuen Li Ion Batterien unterscheiden sich da noch viel mehr, und die ganzen Charging Circuits müssen auch angepasst werden...

Ich kann schon nachvollziehen, wie es dazu kommt, dass Flugzeughersteller sich von den Batterienherstellern die neue Technologie verklickern lassen..

Für einen Electrical Design Engineer ist so eine Li Ion eine herrliche Sache...kleiner, leichter und doch deutlich bessere Leistungen als herkömmliche Ni Cads und Lead Acids..

Die Batteriehersteller sind auch glücklich, haben's doch endlich eine neue Technologie zu verkaufen...eine Li Ion vergeleichbarer Leistung kostet in etwa das 10 -fache einer Bleibatterie, und mindestens das 5 fache einer Ni Cad..

Naja, aber Boeing hat sich meiner Meinung nach mit den Li Ion Main Batts ins Knie geschossen..

wenn man schon ein elektrisch so revolutionäres Flugzeug wie die 787 konzipiert, dann wäre ich wenigstens was die Batterien betrifft, konservativ geblieben..

Und es hätte der Luftfahrtindustrie in dem Fall nicht geschadet sich bei den einschlägigen Autoherstellern im Hybridbereich, z.B. Toyota, gescheit zu machen und zu erforschen was geht und was noch nicht geht...die Toyota und Panasonic Leute wissen ganz offenbar ein oder zwei Sachen über Li Ions, und haben vor Allem viel mehr Erfahrung damit..

Nachdem das NTSB den Vorfall da in Boston bereits untersucht, und auch die FAA eh schon die längste Zeit Muffensausen haben, was Li Ions in Flugzeugen betrifft, wird sich die Sache für Boeing noch auswachsen, und nehme an Boeing wird die 787 in dem Bereich auf konventionelle Batterietechnologie umrüsten müssen...
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BeitragVerfasst am: Di Jan 08, 2013 11:15:24 
Titel: Re: das hier war
Antworten mit Zitat

Viper hat folgendes geschrieben:
...wenn man schon ein elektrisch so revolutionäres Flugzeug wie die 787 konzipiert, dann wäre ich wenigstens was die Batterien betrifft, konservativ geblieben...

Kannst Du in dem Fall nicht, da die batteries ein gewisses "Leistungs-/Gewichtsverhältnis" brauchen, damit das ganze System "Flugzeug" effizient wird. Sonst geht´s je nach dem auf die Zuladung oder die Reichweite, beides wichtige Verkaufsargumente.
Dass die Drecksdinger immer gleich abbrennen oder gar gleich detonieren, ist natürlich blöd...
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BeitragVerfasst am: Di Jan 08, 2013 11:23:40 
Titel: also die paar Kilo.....
Antworten mit Zitat

ich kenn die Specs ein bissel, bei der 787 macht der Gewichtsunterschied zwischen den verbauten Li Ions und NiCads in etwa total 30 Kilo aus...

stimmt schon, Gewicht ist viel Wert...

nur wenn ich die Wahl hab 30 Kilo mehr herumzuschleppen, oder wenn's blöd herkommt irgendwo north of 60° zu verglühen...brauch ich nimmer nachdenken..

Nein, Du wirst sehen, so wie man damals bei der CJ 4 Li Ions Problematik von den "Darwin Awards in Kansas" geredet hat, wird auch die 787 umgerüstet werden müssen..

kommt die Behörde nicht daran vorbei..

Jeder Schei... Sitzbezug in der Kabine muss fire-blocked sein heutzutag..und dann bauens solche Bomben in die Flieger ein..

bin sicher eines nicht all zu fernen Tages werden die Li Ion und Derivate davon sehr safe sein...aber der Tag ist noch nicht da...

und, dass man sowas beim heutigen Stand der Technik nicht in ein Flugzeug einbaut, dazu braucht man keinen dreifachen Dipl.Ing und zweifachen PhD in Aerospace Engineering...dazu reicht Volksschulbildung..

http://www.youtube.com/watch?v=jjAtBiTSsKY

Problem ist sicher auch, was Thales da mit GS Yuasa für die 787 designed hat, das hat 2005 begonnen.....das war ganz am Anfang der Li Ion Technologie...manches wusste man damals noch nicht..


Und wenn man jetzt bedenkt, dass Toyota erst ganz vor Kurzem angefangen hat die neueste Hybrid Generation mit Li Ions auszuliefern, naja...

und wenn im Auto was passiert, mein Gott, bleibt man schnell stehen, steigt aus und geht weit weg...die Option hat man im Flug nicht..

also das war verdammt "mutig" von Boeing damals...und das werden die revidieren müssen..

kann die Behörde nicht daran vorbei..

wenn sich das rumspricht steigt Dir keine Flight Crew mehr in den Flieger ein..
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BeitragVerfasst am: Di Jan 08, 2013 16:26:13 
Titel: Die US FAA
Antworten mit Zitat

hat 2007 für die 787 extra diese "Special Conditions" gemacht, um die 787 überhaupt mit Li Ions zulassen zu können...war und ist bis heute in den Bauvorschriften nicht wirklich gecovered...für so Fälle gibt's dann die "Special Conditions" etc

Zitat:
...These special conditions are issued for the Boeing Model 787-8
airplane. This airplane will have novel or unusual design features when
compared to the state of technology envisioned in the airworthiness
standards for transport category airplanes. The Boeing Model 787-8
airplanes will use high capacity lithium ion battery technology in on-
board systems. For these design features, the applicable airworthiness
regulations do not contain adequate or appropriate safety standards.
These special conditions contain the additional safety standards that
the Administrator considers necessary to establish a level of safety
equivalent to that established by the existing standards. Additional
special conditions will be issued for other novel or unusual design
features of the Boeing Model 787-8 airplanes.......


.....

Large, high capacity, rechargeable lithium ion batteries are a novel or
unusual design feature in transport category airplanes. This type of
battery has certain failure, operational, and maintenance
characteristics that differ significantly from those of the nickel-
cadmium and lead-acid rechargeable batteries currently approved for
installation on large transport category airplanes. The FAA issues
these special conditions to require that (1) all characteristics of the
lithium ion battery and its installation that could affect safe
operation of the 787 are addressed, and (2) appropriate maintenance
requirements are established to ensure the availability of electrical
power from the batteries when needed......

...1. Overcharging

In general, lithium ion batteries are significantly more
susceptible to internal failures that can result in self-sustaining
increases in temperature and pressure (thermal runaway) than their
nickel-cadmium or lead-acid counterparts. This is especially true for
overcharging, which causes heating and destabilization of the
components of the cell, leading to formation (by plating) of highly
unstable metallic lithium. The metallic lithium can ignite, resulting
in

a self-sustaining fire or explosion. Finally, the severity of thermal
runaway from overcharging increases with increasing battery capacity,
because of the higher amount of electrolytes in large batteries.....


http://www.gpo.gov/fdsys/pkg/FR-2007-10-11/html/E7-19980.htm

also ich gehe jede Wette ein, dass diese Special Conditions "within weeks" storniert werden, und Boeing sich eine Alternative wird einfallen lassen müssen..

Wenn neue Flugzeugmodelle bei Indienststellung das potentielle Problem haben, von sich aus in Flammen aufzugehen, sowas läuft nie mehr unter "teething troubles", da geht's ans Eingemachte, da spielt die Behörde nicht mit, darf sie auch nicht...

Schätz innerhalb einer Woche jetzt wird es ein diesbezügliches EAD, "Emergency Airworthiness Directive", für die B 787 geben....und das kann bis zum sofortigen Grounding der gesamten bis jetzt in Betrieb befindlichen Flotte gehen..bis man halt eine tragbare technische Lösung gefunden haben werden wird..
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BeitragVerfasst am: Di Jan 08, 2013 21:05:32 
Titel: Murphy's Law...
Antworten mit Zitat

Die JAL hat kein Glück mit ihren neuen 787...heute musste ein Boston - Tokyo Flug in Boston zurück wegen eines Fuel Leaks..

http://www.boston.com/metrodesk/2013/01/08/fuel-leaks-from-dreamliner-flight-tokyo/bL83P1vSeCRjSeOfsWXlXM/story.html

auf dem Photo sieht man hinter diesem Flieger den "Batteriegeschädigten" noch geparkt..

Die Köpfe sowohl bei Boeing, der FAA und dem NTSB rauchen jedenfalls...

wie gesagt einen Präzedenzfall was Li Ions betrifft, unter ganz ähnlichen Umständen gab es ja 2011 mit dem Cessna Citationjet 4..

da gab's ruckzuck ein Emergency AD von der FAA...und die Kisten mussten auf konventionelle Batts rückgerüstet werden

man wird sehen....

kann mir persönlich nicht vorstellen, dass man von FAA Seite die 787 mit einer suspekten Li Ion Batteries Installation so ohne Weiteres weiterfliegen lässt...

Die Dinger sind immerhin "hard 330 Min ETOPS" zulassbar unterwegs..zumindest sind die sagenhaften 330 Min ETOPS ein Designtarget..

derzeit wird die B-787 mit 180 Min ETOPS Capability ausgeliefert...was mit ein paar Abstrichen für das Gros der Trans Pacificflüge reicht..


Zuletzt bearbeitet von Viper am Mi Jan 09, 2013 10:59:24, insgesamt einmal bearbeitet
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BeitragVerfasst am: Di Jan 08, 2013 23:02:32 
Titel: Eines lässt sich leider
Antworten mit Zitat

jetzt schon zweifelsfrei feststellen...

Die PR und Kommunikationsstrategie von Boeing ist anlässlich der Vorkommnisse derzeit katastrophal. Nämlich nicht existent und nicht wahrnehmbar.

In so einem Fall MUSS man offen und transparent an die Öffentlichkeit gehen...

Boeing ist allerdings derzeit auf Tauchstation...das kommt nicht gut

das verwundert mich schon sehr..
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BeitragVerfasst am: Mi Jan 09, 2013 11:26:46 
Titel: Dieser Artikel hier
Antworten mit Zitat

bringt die Diskussion auch bei den Batterieherstellern, was den derzeitigen Stand von Li Ion Batts, als Main Ship Batts betrifft recht gut heraus..

Zitat:


Lithium Ion for Aviation

December 13, 2012

It holds promise for higher capacity batteries, but also risks for fires and explosions. Owners should tread cautiously.

For the great wide world of transportation, the lithium-ion battery is the shining city on the hill, that pivotal bit of technology that will have us whizzing around in silent cars banishing the evils of carbon dioxide. For aviation, lithium-ion is both an enigma and an opportunity. To understand both, you need only to grasp three numbers: 50, 150 and 1700. The opportunity part resides in the first two numbers -- a lead-acid battery's energy density is about 50 Wh/kg, a third or less than that of the typical lithium-ion's 150 Wh/kg. Now for the enigma. The 1700 is the Wh/kg energy content of gasoline, adjusted for the typical internal combustion engine's 20 percent efficiency. The very best lithium-ion batteries can do at the moment is 400 Wh/kg and these don't exist commercially yet. That means the practical electric airplane may be on the horizon, but it's not around the corner.

Lithium batteries ought to be a slam dunk for one application, though: starting and main aircraft batteries. "They're twice the capacity and half the weight," says Skip Koss of Concorde Battery, a leading GA supplier. The only thing is, he says, they've been known to erupt in violent flames from time to time, thus Concorde isn't satisfied that the technology is yet worth the risk.

The Cars Are Driving

The market for lithium-ion batteries in aviation is bifurcated and although not strong yet, it's certain to go that way. What's driving development, including capacity improvement, new chemistries and safety, is the emerging electric vehicle market. But two other segments are promising, too: grid batteries that are used for smoothing out and backing up commercial electrical grids and IT/data applications. Aviation will be a fraction of this, but it's still seen as a growth market.

For aviation, primary batteries for electric airplanes have thus far been based largely -- although not exclusively -- on the lithium-cobalt-oxide technology that's popular for notebook computers. Panasonic and Sony are big players in these markets and these batteries find their way into developmental airplanes through companies that buy the individual 3.6-volt cells and custom package them for specified voltages and amp-hour requirements.

The battery pack in the PC-Aero Electra One Solar electric airplane we saw in Germany last spring uses a 60-volt system that PC-Aero's Calin Gologan told us is a compromise between safety and efficiency. Electric airplanes have been -- and remain -- hamstrung by battery energy density considerations. Even though the best mass-market lithium-ion technology is now capable of nearly 200 Wh/kg, twice that density would make them more marketable.

Panasonic, whose batteries Gologan uses in the Solar One, promised higher watt density batteries, but hasn't delivered. "The technology exists. I think they don't bring it for economical reasons. They don't want to start to the production lines," Gologan says. Meanwhile, PC-Aero has equipped its soon-to-be intro airplane with solar cells that can extend flight time by 50 percent. Gologan believes for the fly-for-fun market that electric airplanes will represent initially, 90 minutes to a couple of hours of slow-speed endurance is sufficient and he believes currently available batteries can do that. Obviously, if electric airplanes are to become serious contenders in, first, the training market and later personal transportation, better batteries are a must. Everyone in this field we spoke to tells us they're sure these are coming, but no one knows when or what their capacity will be.

In Slovenia, innovative Pipistrel has been offering an electric version of its Taurus G2 motorglider since 2007. Total sales so far? One, although more are expected to ship this year. Current battery technology allows two climbs to 4000 feet, followed by 3.5 hours of charging, says Pipistrel's Tine Tomazic, who takes claims of battery capacity doubling within five years with a pound of salt. "Since 2007, when we flew the prototype G2, the energy density went from 163 (Wh/kg) to 185 for the same power required," he said. That's not much progress in five years, although Pipistrel says it's confident enough in better batteries to plan an all-electric version of its new Panthera and also an electric Alpha trainer. Meanwhile, Pipistrel is also developing a hybrid.

Where Are the Batteries?


With the industry stuck at the 200 Wh/kg barrier, if not practically a lot less, where and when is this new battery capacity supposed to appear? These turn out be difficult questions to pin down. We spoke with Bill Mitchell, VP of commercial solutions at A123, a startup company that has become a leader in EV batteries but who also sees potential in aviation. A123 is championing a lithium-iron-nanophosphate technology that it claims has good energy density and is more stable than the cobalt-oxide chemistries that currently dominant the market. The holy grail of lithium efficiency is to move lithium ions through the electrolytes and electrodes more efficiently and A123's nano-size particles do that, says Mitchell. Further, because they vent when thermally stressed, they're less volatile than oxide batteries, whose electrolytes of lithium salts dissolved in flammable organic solvents are highly susceptible to intense fires.

(A123's claims notwithstanding, its cells were used in a Citation that torched in a battery fire last year. More on that later.)

Mitchell told us the working nameplate energy density of today's cells is 130 to 150 Wh/kg and he sees that doubling over the next few years. "Few" is fuzzy, but if it's three to five years, that's unlikely to shift the electric airplane market into high gear.

Pipistrel's Tomazic said doubling energy density would open up some possibilities, such as two more takeoffs in the G2 motorglider before recharge or more "get home" energy from a longer flight. He reckons most operators would opt for the takeoffs and use the G2 as a glider trainer. What about longer term? "Ten years from now? The crystal ball gets a lot more cloudy," says A123's Mitchell. "There are a lot of chemistries out there that have promise to increase energy density, but they're still at the early stage."

One of those was revealed at last spring's CAFE Electric Aircraft Symposium in Santa Rosa, California, where battery researcher Cary Hayner from Northwestern University discussed what has become know as "10X" technology, implying a ten-fold increase in energy density. "The 10X issue is a bit tricky," Hayner told us via e-mail. "Although we increased the capacity ten-fold in the anode electrode -- you can also say equivalently that we increased the anode energy density (Wh/kg) by roughly ten-fold as well, maybe slightly less, like eight-fold -- consumers will not be able to see the ten-fold increase in energy in electronics on the market," he explained.

That's because the cathode hasn't been upgraded yet, although even with current technology, Hayner believes the new anodes could improve energy density by 30 or 40 percent, and the new anode may be commercially viable with current cathodes over the short term. "To fully realize the ten-fold increase in energy density, we would need to couple our anode technology with an oxygen cathode electrode, which may not be feasible for many more years -- this is what is called 'Li-air' technology," Hayner said. The Northwestern team improved energy density by inserting "in-plane" defects in their graphene anode material, allowing more efficient movement of lithium ions.

A Citation Burns

That lithium batteries bring promise with peril was illustrated by Cessna's recent experience. In a well-suppressed event in Wichita last fall, a Citation CJ4 equipped with a lithium-ion battery with A123 cells caught fire and burned, according to an FAA-issued AD on the incident. We're not sure if the airplane was a hull loss, but it sustained significant damage. Neither Cessna nor A123 replied to our requests for additional detail. Whatever the case, Cessna immediately issued a recall service bulletin to remove lithium-ion batteries for about 50 CJ4s and on October 6, 2011, an emergency AD appeared requiring the same. The batteries were replaced with lead-acid or NiCad, by owner choice. Cessna did say it is committed to lithium-ion technology and hasn't given up trying.

Significantly, the Citations had battery installations approved by the FAA, which has expressed serious reservations about lithium ion for aircraft main batteries and has developed stringent certification requirements. According to the FAA, since 1991, there have been 53 aviation-related incidents -- fires and minor explosions -- involving consumer-grade lithium-ion batteries. These have occurred on cargo aircraft, passenger aircraft and in terminals.

(To be fair, lead-acid, NiMh and NiCads have also been involved in more incidents.)

It's possible, if not likely, that two major hull losses have occurred because of lithium battery fires, both in UPS aircraft. One occurred in Philadelphia in 2006, the other in Dubai in 2010. The latter, a 747, was carrying 81,000 lithium-ion batteries, but in neither case could investigators say with certainty that the batteries ignited the fires. Nonetheless, the risk is viewed as so serious that the FAA restricted passenger airplanes from carrying non-rechargeable lithium batteries as cargo in 2004 and new regulations will go into effect next year requiring more stringent labeling and packaging. Without these, a study by ICAO predicted an aircraft loss every two years due to battery fires. All of this tends to taps the brakes on lithium batteries for GA.

What's the Problem?


The principle source of volatility in lithium-ion batteries is their highly flammable lithium salt and organic solvent electrolytes. Lithium metal itself is highly volatile, but only small coin or camera cells have metallic lithium. That's a good thing, for these have been implicated in some lively small-scale explosions.

Although lithium chemistries vary in their sensitivity to overcharging, a single overcharged cell in a pack can initiate thermal runaway. "When one goes, it tends to propagate to the other cells and you have a real problem," says Concorde's lithium-ion expert, Dave Vutetakis. A single cell is difficult to extinguish, but with several popping off, losing the airplane is likely and this may have been what happened in Cessna's Citation fire. Lithium-iron nanophosphate -- A123's specialty -- is considered one of the most stable chemistries, but it still has a hull fire on its record.

Several layers of redundant protection are thus needed, starting with electronic battery management systems (BMS) that monitor the cell temperature and keep charge rates balanced. BMSs also keep the battery from discharging entirely, in which case it's ruined. "I think it would be foolhardy to market a lithium-ion battery without good electronics," Vutetakis said. A robust enclosure is also a good idea, although that obviates some of the weight savings. Vutetakis says the electronics can't protect against one risk: internal cell shorts. This can and has happened. "That's why you had the big battery recalls for laptops," he told us. Cell shorting is a risk for all-electric airplanes, but the charging risk is much less because this occurs only on the ground. In either case, the risk may be statistically low, but the consequences are severe.

If it sounds like lithium-ion will never make it into GA starting batteries, it already has. A company called Aerovoltz is marketing lithium-iron-phosphate batteries through Aircraft Spruce for experimental applications. The company's Steve Johnson told us it has thousands of A123-cell Li-ion in the motorsports market with no safety issues. The battery cases are hardened against flame propagation. It's also developing BMS options. Mid-Continent Instruments and Avionics recently announced that it will begin marketing A123's cells, albeit not finished batteries. Mid-Continent is already marketing a line of certified Li-ion backup battery units.

As for certified aircraft, Concorde says lithium-ion will come eventually, but it'll be awhile. Skip Koss told us he doesn't yet see much market for batteries that are definitely lighter than the best lead-acid models and more energy dense, but that will also cost four to five times as much. And Concorde says it won't move forward until it's comfortable that the Li-ion risk is lower than it is now.

We agree that taking this one slow is the way to go.

This article first appeared in the August 2012 issue of Aviation Consumer magazine. See the full article at AviationConsumer.com.


http://www.avweb.com/news/redundant/airplane_battery_technology_electric_solar_flight_207845-1.html

wie gesagt, sowohl z.B. Concorde, als auch SAFT sind sehr bekannte und erfahrene Hersteller von Batterien für die Luftfahrt, kennen sich also ein bisserl aus mit der Materie, haben aber beide noch keine Li Ion Main Ship Batts im Programm....

sind beide sehr prominent auch bei herkömmlichen Boeings, Airbüssern, also generell sowohl im zivilen als auch im militärischen Bereich als zuverlässige Batterielieferanten bekannt..

http://www.saftbatteries.com/MarketSegments/Aircraft/tabid/362/Default.aspx

http://www.concordebattery.com

Securaplane wiederum, auch ein bekannter Hersteller, sind auf der "mutigeren" Seite und stellen die Li Ion Main Ship Batt, die in der neuen Gulfstream G 650 verbaut ist her..., sorry, correction, die sollen erst in Zukunft auf der G650 verbaut werden, ist noch nicht Serie...

man wird sehen...

http://www.securaplane.com/products/energy-storage-technologies

Hier noch ein früherer Artikel, der auch auf den Punkt kommt..

Zitat:
...Some aviation battery manufacturers—Concorde is one—are reluctant to aggressively offer lithium-ion for safety and cost reasons, but mostly safety. The FAA has expressed reservations about lithium-ion technology in airplanes and apparently with good reason.

Obviously, the agency has stringent requirements for certification of aircraft lithium batteries, but the industry was surprised to learn that this wasn't enough to prevent a lithium-ion battery from lighting off in a Cessna Citation CJ4 last year. Neither Cessna nor the makers of the cells, A123, would comment on what happened to cause that fire, but Cessna quickly withdrew the batteries from the Citations and the FAA issued an emergency AD. Cessna says it's still committed to Li-ion, but declines to offer details. Ironically, A123's cell technology—lithium-ion nanophosphate—is considered the most stable of the principle lithium chemistries, yet it still notched an aircraft hull fire.

The risk of lithium-ion battery explosions and fires, while low, is complicated by their potential severity. Once it ignites due to thermal runaway, a lithium battery fire is difficult if not impossible to extinguish and it will often lead to a chain reaction, igniting neighboring cells. For airplanes, the nature of the risk is bifurcated. For starting batteries which must be charged in flight, an overcharge/imbalance in one cell can lead to thermal runaway. Li-ion technology is equipped with electronic protection to prevent this and also to keep the batteries from discharging to zero, which will trash them.....


http://www.avweb.com/blogs/insider/AVWebInsider_Batteries_206994-1.html


Zuletzt bearbeitet von Viper am Do Jan 10, 2013 13:29:00, insgesamt einmal bearbeitet
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BeitragVerfasst am: Mi Jan 09, 2013 21:53:45 
Titel: nur noch ein letztes Detail
Antworten mit Zitat

zum Schildbürgerstreich von Boeing in das neue Baby Li Ions reinzubauen, zu einem Zeitpunkt als alle bekannten Flugzeugbatteriehersteller gegen ihre eigenen kommerziellen Interessen aus Sicherheitsgründen davon abgraten haben..

Die neuen Li Ion Aircraft Main Batt Hersteller sind ja alle eher unbekannt in Branchenkreisen ( auch Securaplane, die die Li Ion für die G 650 machen, sind eher ein Newcomer im Battbereich..die haben vor Jahren angefangen mit Sicherheitssystemen ( gegen Einbruch) auf Flugzeugen und haben dann erst mal im Stand By Batteriebereich den Batteriemarkt angefangen...)

Die Gulfstream G 650 die jetzt erstmals ausgeliefert werden, haben meines Wissens noch NiCads installiert. Gulfstream plant den Upgrade auf Li Ion erst, wenn sie sich wohlfühlen damit. Also was Securaplane da entwickelt hat für Gulfstream ist noch nicht Serie.

Im Jahr 2008, als Boeing im Protohangar zum ersten Mal Power auf den ersten 787 gegeben hat, dürft sich was abgespielt haben...

das klang dann so, eher höflich umschrieben...

Der Bericht ist aus dem Jahr 2008.......

Zitat:
....As Boeing activated the electrical system of its 787 for the first time last week, the airframer acknowledged that it was exploring a change to its power system for production aircraft due to longevity concerns.

Boeing will move away from its original lithium ion battery design for its main and auxiliary power units,
flight-control electronics, emergency lighting system and recorder independent power supply. Instead, Boeing is investigating the incorporation of manganese inside the lithium ion battery to boost service life......


http://www.flightglobal.com/news/articles/boeing-looks-to-boost-787-lithium-ion-battery-service-life-224663/

wahrscheinlich hat's damals zu ersten Mal zum Rauchen angefangen in einer Battery Bay.....
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BeitragVerfasst am: Do Jan 10, 2013 12:47:05 
Titel: die grundsätzlichen
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"Anfangsprobleme" der 787 sind ja verständlich, wenn auch an Anzahl etwas hoch, wenn man bedenkt, dass nach den Verzögerungen in Entwicklung nun auch die Produktionsrate an zwei verschiedenen Standorten hochgefahren werden muss, während die Flieger die derzeit ausgeliefert werden, ja schon vor längerer Zeit gebaut worden waren und im letzten Jahr sehr aufwendig auf den letzten Stand gebracht werden mussten..

wie gesagt ich finde, dass die 787 ein sehr interessantes und zukunftweisendes Flugzeug ist..

und naja, ob da jetzt bei einem Flieger eins Tages ein Tank Vent Valve nicht zu ist und er zurückrollen muss vor dem Start, oder bei einem anderen halt eine Brake Message kommt und die Crew zurückrollen muss...das ist zwar nicht erfreulich, aber den Umständen entsprechend auch nicht so ungewöhnlich und leicht beherrschbar...und das werden die Boeing Leute fixen..

Das läuft wirklich Alles unter "teething troubles"...wegen solcher Sachen fällt kein Flieger vom Himmel...

Gut, dass bei einer 787 vor Kurzem bei einem Production Test Flight sich die neue GE Engine "halb- uncontained" zerlegt hat nach dem Start...naja, sofern GE glaubwürdig nachweisen kann, dass man das Problem auf ein Productionbatch von Wellen, bei denen bei der Produktion beim Heatreatment was falsch gelaufen ist eingrenzen kann...wie gesagt auch nicht ganz so ungewöhnlich..

Aber wie gesagt die Feuersache da mit der Li Ion Batterie, das hat einfach eine andere Qualität....

und da verwundert mich die Aussage des Chief Design Engineers von der 787 von Boeing doch etwas..

Die Aussage deutet auf eine gewisse "Verstocktheit" hin, und/ oder die ganze neue elektrische Architektur der 787 ist so tief ins System bereits auf die Leistungscharakteristik der beiden Li ION Main Ship Batts ausgelegt, dass Boeing gar keinen "einfachen" oder auch nur temporären Weg zurück hat.. ob es aber in der Macht von Boeing liegt da zu entscheiden wie das weitergeht, wenn die findings von dem Battery Incident heraus sind ist auch noch die Frage..

Zitat:
...

Boeing insisted on Wednesday that the 787's problems are no worse than what it experienced when its 777 was new in the mid-1990s. That plane is now one of its top-sellers and is well-liked by airlines.

"Just like any new airplane program, we work through those issues and move on," said Mike Sinnett, the 787 chief engineer. He added, "We're not satisfied until our reliability and our performance are 100 per cent."

Sinnett didn't say so, but other new planes have had issues, too, including the Airbus A380 superjumbo. Small cracks have been discovered on the wings, and in 2010 a Rolls Royce engine on a Qantas flight exploded in mid-flight.

He said the nature of lithium ion batteries means no fire extinguisher system will stop them from burning once they start. The NTSB said it took firefighters 40 minutes to put out Monday's fire.

Sinnett said Boeing has no plans to replace the lithium ion batteries with another type. If he had to re-do the choice to go with lithium ion, he said, he'd make the same choice today.


http://www.theaustralian.com.au/news/world/boeing-defends-dreamliner-although-safety-questions-remain/story-e6frg6so-1226551064745
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BeitragVerfasst am: Do Jan 10, 2013 15:30:22 
Titel: Anfang nächster Woche
Antworten mit Zitat

ist sicher mit behördlichen Vorschlägen, respektive Lufttüchtigkeitsanweisungen seitens der FAA zu rechnen...

Ich glaube nach wie vor nicht, dass die neue elektrische Architektur der 787 irgendwelche besonderen Design Flaws hat..

Eher scheint es wirklich so zu sein, dass die Designstrategie sich was den neuen Batterietyp betrifft ein bissel verirrt hat...

Vergessen wir nicht, eine Batterie ist nach wie vor ein "consumable", egal welcher Batterietyp, nach einer gewissen Betriebszeit muss sie sowieso entsorgt werden...

Und eben ein ganzes elektrisches System argumentativ an einem "consumable" wie der Batterie "aufzuhängen"...das ist nicht unbedingt die "Alte Boeing Design Schule"...

Zitat:


....People familiar with the investigation, however, said high-level Federal Aviation Administration officials are increasingly concerned about the spate of electrical problems, highlighted by the smoldering battery aboard the JAL jet, that have dogged the aircraft since its introduction.

No additional mandatory safety fixes or government-ordered inspections of Dreamliners are expected for at least the next day or two, partly because FAA and NTSB experts still are trying to determine the specific cause of the battery fire. But perhaps as soon as early next week, according to one person familiar with the matter, regulators may call for some type of review or reassessment of design and manufacturing issues related to the Dreamliner's electrical systems. The Dreamliner uses electricity for more functions than any previous jet developed by Boeing.

The FAA's internal deliberations, according to another person familiar with them, also include other options and may take longer to conclude.

FAA officials reiterated that the investigation of the JAL incident is continuing. An NTSB spokesman said "it is very early in the investigation, and we are still gathering facts." He said the safety board "will issue additional information as it becomes available."......


www.wsj.com
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BeitragVerfasst am: Do Jan 10, 2013 19:09:54 
Titel: Der Paul Bertorelli
Antworten mit Zitat

von avweb.com ist ja auch ein Skeptiker, was was den Einsatz von Lithium Ion Batterien in Flugzeugen betrifft....und hat das auch schon längere Zeit recheriert und meldet sich auf seinem Blog zu Wort..

Zitat:


The Dreamliner's Battery Fire

By Paul Bertorelli




I'll bet the broadband video conference lines between Boeing, Yuasa and Thales are getting overtime use this week following Monday's ground fire in a Boeing 787-8 Dreamliner at Boston's Logan airport. The instant I saw the video of it, with smoke curling out of the after hatch, I thought to myself, that better not be a battery issue. But it now appears that this is exactly what it was.

This is serious stuff for Boeing and could put a significant dent in the airplane's certification basis if they can't figure out a solution. When Boeing proposed the Dreamliner a decade ago, it spec'd lithium-ion batteries for the airplane's innovative electrical power conversion system, which is made by Thales, with batteries from Yuasa. The Li-ion cells provide starting energy for the APU and back-up power for other systems. At the time, the hazards of Li-ion were known, but Boeing wanted the weight savings and power density that only Li-ion can offer. Working with the FAA, it developed new certification standards for batteries under so-called special conditions. That required sophisticated electronics to provide overcharge and charge imbalance protection and physical thermal containment. Taken together and on paper, those precautions look more than robust enough to meet the stringent safety requirements of a modern airliner.

Well, maybe not. When I was researching Li-ion batteries for aircraft last year, I heard real concerns that the Li-ion main/starting battery risk wasn't yet well understood. As I reported, Cessna already lost one Citation to an Li-ion ground fire and withdrew Li-ion batteries as an option, at least temporarily. Now comes the 787 incident that might have gone the same way if it hadn't been caught early. It's also possible that the fire wouldn't have gotten any worse and that despite the smoke, the thermal containment worked. Of that, I'm not so sure. Early reports suggest the battery pack was well into progressive thermal runaway, with one failed cell torching off another. We'll see what the investigation reveals. The 787 is an ETOPS-330 airplane, meaning it can legally fly routes more than five hours from a diversion airport. That's a long time to have a smoke-filled cabin. Or worse.

The 787's flaws have been well publicized and the industry has made cooing noises that this is just normal teething pains that every airplane has experienced. That may be correct, although it's hard to compare the 787 to other airplanes because it's such leap forward in terms of all-electric sophistication. It's bound to have bugs. But I wouldn't consider an Li-ion battery fire a bug, so much as a confirmation that those who think Li-ion isn't ready for commercial airplanes could very well have a point.

Li-ion batteries runaway for three main reasons: They're sensitive to charging imbalance between cells, cells themselves short and external heat can ignite the highly flammable electrolytes. Once burning, they're hard to put out. Li-ion batteries are finding their way into vehicle markets, driven by the hybrid and electric vehicle push, but also as standard starting batteries in some new models. The record for these early adoptions seems good, both in performance and safety. But the Li-ion battery universe is still small. Flooded cells and AGM have been implicated in a few fires, too, but there are orders of magnitudes more of them out there.

I have five motorcycles in my garage, each with a blinking battery tender. I could replace the flooded cells with Li-ion, get more starting capacity for less weight, albeit at three times the cost. I haven't done that yet because I don't think the technology is quite ready for prime time and I don't care about the weight. Plus, I'm cheap.

Boeing obviously felt differently. I sure hope they're proven right.


http://www.avweb.com/blogs/insider/AVwebInsider_DreamlinerFire_207979-1.html

es lohnt sich den Bericht anzuklicken, da ist das Bild drinnen von dem angebrutzelten Aft Elec Bay Compartment, wo man den NTSB Inspektor bei der Untersuchung sieht von dem neuen JAL Flieger...

Eines fällt mir da schon zusätzlich auf, scheint mir von der Location schon ein bissel gewagt, dass das problemtische Batteritscherl da unten "freisteht", die Batterie ist dort eingebaut wo der NTSB Inspektor seine rechte Hand hat...und in der Aft Elec Bay sind aber nehm ich mal an mitunter die wichtigsten Büchsen verbaut, was die Stromversorgung vom Flieger betrifft....da fragt man sich schon...anstatt, dass man die Batterie wenigstens abseits in ein eigenes Kompartment mit einem zusätzlichen Containment einbaut..naja, aber das würde den Gewichtsvorteil wiederum neutralisieren....

also ein bissel sehr "hemdsärmelig" kommt mir die Sache von Seite von Boeings Designleuten schon vor...

und das beim bis jetzt offenbar kostspieligsten Flugzeugprogramm in Boeing's Geschichte

was man vielleicht ergänzen könnte zu Bertorelli's Bericht ist, da liegt der Bertorelli ein bissel falsch, er schreibt, Boeing und die FAA hätte mittels "special conditions", ich hab's weiter oben verlinkt, ganz strenge Zulassungsvorschriften für die Li Ions entwickelt..

das stimmt so nicht...

"special conditions" heisst nichts anderes, als, dass man mit den bestehenden und gültigen Bauvorschriften und Sicherheitsbestimmungen nicht auskommt, weil die neuen Batterien die halt nicht erfüllen ( können) und dass die Behörde halt versucht, das was sie für sinnvoll hällt, anstatt der gültigen Bauvorschriften, vorzuschreiben, um einen ELO (equivalent level of safety) zu erreichen..

Die Behörde, in dem Fall die FAA, ist da aber in so einem Fall zum Grossteil von den Infos und Tests abhängig, die der Batterienhersteller liefert...also diese "special conditions" heissen nicht automatisch, dass das dann unbedingt safe abläuft....sondern viel mehr, dass auch die Behörde nicht wirklich einen Tau hat, wie sie das zulassen sollen...aber papermässig sind sie mit den "special conditions" sozusagen aus dem Schneider...
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BeitragVerfasst am: Do Jan 10, 2013 23:37:22 
Titel: OOOooops.......
Antworten mit Zitat

naja.....

unten verlinkt ein aktueller Bericht zum Thema aus "Aviation Leak.."

Zumindest eine "Fachzeitschrift" die Aviation Week..

Jetzt weiss ich nicht, entweder die Medien werden immer schlechter oder, was auch sein kann, ich hab vor 30 Jahren sicher nicht den Background gehabt, den ich jetzt hab, und hab halt damals zuviel von dem geglaubt, was da drinnen gestanden ist...wahrscheinlich stimmt Beides...

Nur hier in dem Artikel offenbart der 787 Project Engineer von Boeing, der Sinnett wahrscheinlich eher unbewusst, aus welcher Denkschule er kommt..

Der Artikel an sich ist ganz OK, das übliche Blah, Blah halt..

Dann kommt es eben zum "corpus delicti" von Boston, dem Li ion Bomberl da auf der schönen neuen JAL 787...dem bisher ganz sicher kritischsten Problem...weil wenn der JAL das passiert wär "im Flug" irgendwo weit weg von überall north of 60° am Weg von Tokyo nach Boston...na Dank Schön....

naja...

das Übliche Blah Blah halt...

aber dann......

Zitat:
....In April 2007, however, the FAA issued a notice of proposed special conditions concerning the use of lithium ion batteries on the 787 in which it noted that these types of batteries “are significantly more susceptible to internal failures that can result in self-sustaining increases in temperature and pressure (thermal runaway) than their nickel-cadmium or lead-acid counterparts.” The agency said overcharging, in particular, could result in a “self-sustaining fire or explosion.”

Sinnett says, “Because they’re lithium ion, they contain a lot of energy and can release it quickly. Unless you design it appropriately, that can be a problem. When it’s overcharged it can carry more than it is designed for. It’s designed so you can never overcharge it. We’ve got multiple redundancy built into the system. Two [safeguards] are built directly in the battery, and two are located outside and are independent of the battery. So it is protected with multiple layers. We demonstrated by test and analysis that we are sufficiently safe.”

Presenting other scenarios, Sinnett explains that “there are a number of things that can cause a single cell to overheat, to discharge and then to vent smoke and–if it gets hot enough–to burn. One is over-discharge, in which you let the battery go down too low over successive periods. That can cause damage and lead to a short circuit. So we protect against it by putting in a circuit which protects it from over discharge or over charging.

The only other [possibility] is that over-heating of cells could cause them to vent, or a manufacturing defect could cause a short circuit. But we’ve had 1.3 million hours of operation in flight, and we’re pretty confident in the overall design. However we can’t assume anything, so if there was a manufacturing defect that would lead to a discharge of potential energy we’d expect the battery cell to vent–which looks like smoke. If the system detects smoke, it configures the airflow so that it goes through the E/E bay and goes overboard. If there’s any failures we know of that’s how it would work.”


http://www.aviationweek.com/Article.aspx?id=/article-xml/awx_01_09_2013_p0-534945.xml&p=1

Der gute Mann multipliziert offenbar die individuellen Battery Cells mit den Flugstunden der Flotte bis jetzt...Testhours und Ops Hours bei Kunden...

weil anders kommt er ja nie auf 1.3 Mio Stunden....die ganze 787 Flotte, also Tests und das was die Airlines bis jetzt schon geflogen haben sind in etwa 50.000 Stunden bis heut...

ganz schwerer Denkfehler...die Battery als Einheit und System, egal wie viele Zellen da jetzt drinnen sind, ist auschlaggebend...

und auf den Batteries als System habens bis jetzt höchsten "in flight" naja die Flugstunden die die Flotte bis jetzt drauf hat..sicher auch noch unzählige Stunden am Boden bei Tests.....

und aufgrund der Basis ist er "pretty confident".....

Gut, die Realität ist, dass die FAA und das NTSB dem guten Mann derzeit die Hölle heiss machen, nach dem Motto, "we told you so..." aber da haben's ein Pech, weil mit den "special conditions" waren's dabei die FAA..

gehe jede Wette ein, dass der FAA bis Montag die Sache endgültig zu "heiss" geworden sein wird, und sie sich heute bereits, oder vielleicht schon seit Längerem eine Wendeltreppen in den eh--scho-wissen beissen, weil's bei dem Li Ion Spiel mitgetan haben..bei der Zulassung..

Der richtige Weg von Boeing wär gewesen, eine "dual track" Strategie, heisst die 787 mal z.B. mit Ni Cads rasuzubringen und gleichzeitig halt die Entwicklung bei den Li Ions am Laufenden zu halten umd dann, wenn die Dinger mal kontrollierbar safe sind umzurüsten..

Kann wohl sein, dass Boeing sich wegen der depperten Batterieentscheidung, ganz schwer ins Knie geschossen haben...

weil ab jetzt rennt der Taxameter und ab jetzt kostet es dann wirklich viel, die Sache wieder in Ordnung zu bringen...

ein Poster in Aviationweek unter dem Artikel bringt es auf den Punkt..

Zitat:
Lithium Bats. are like a beautiful girl who has everything you've ever dreamed of, but, she goes completely nuts once in a while. Its bad enough when it happens in a car, on the ground.
Layman has the right take; Stick with ni-cad, it's heavier and less power, but it does'nt set your plane on fire.
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BeitragVerfasst am: Fr Jan 11, 2013 10:01:19 
Titel: FAA Special Review
Antworten mit Zitat

Zitat:


FAA to Launch Review of Boeing's 787 Dreamliner


By ANDY PASZTOR And JON OSTROWER

The Federal Aviation Administration, increasingly concerned about safety and reliability issues surrounding Boeing Co.'s 787 Dreamliner, on Friday plans to launch a top-priority review of the plane focusing on its electrical system and quality controls used in the manufacturing process.


The unusual move comes after the agency has spent months monitoring various electrical problems and other operational glitches affecting the planes, according to people familiar with the matter, but was specifically prompted by a battery fire on Monday aboard a Japan Airlines Co. 787 on the ground in Boston.

Industry and government officials said the anticipated review—slated to be headed by officials from the FAA's new-plane certification and transport directorate offices—marks the first time in recent years that the agency has gone back to reassess the safety of specific systems in a jetliner already in revenue service.

Nobody was hurt in this week's incident, but it ratcheted up pressure on the FAA to announce steps to find the root cause of the blaze and determine common factors that may have affected earlier problems stemming from improperly assembled wiring and other electrical issues.

The FAA's lead spokeswoman declined to comment.

A Boeing spokesman declined to comment on "the nature and content" of the company's communications with regulators, but said "we are working with the FAA and our customers to ensure we thoroughly understand" issues pertaining to introduction of the plane into widespread service. Spokesman Marc Birtel added, "we are absolutely confident in the reliability and performance of the 787."

The review won't ground planes or halt production, but the FAA has broad latitude to take action as a result of any findings. That could range from ordering new production procedures to revising designs of some electric components, which potentially could prompt further production delays and additional costs for Boeing.

In addition to reviewing technical and safety questions related to the design of the 787's groundbreaking electrical system, the FAA also will delve into manufacturing issues such as how well subcontractors are integrated into Boeing's overall production system, according to one person familiar with the details.

The decision to launch the review is bound to stoke concerns on Wall Street about potential negative fallout to Boeing's reputation and stock price. But the move also carries some political risks for Michael Huerta, the recently confirmed chief of the FAA, who now must oversee a high-profile review that could reopen some safety and manufacturing issues the agency was supposed to put to bed before it certified the Dreamliner in late 2011.

U.S. aviation regulators raised questions about the reliability of the Dreamliner during long transocean flights months before the advanced new jet suffered a spate of electrical and other problems this week, according to people familiar with the matter.

The ability of the Dreamliner to fly long routes, such as the 7,400-mile trek between Houston and Auckland, New Zealand, was touted as one of the plane's game-changing characteristics by Boeing and airline customers alike, with the jet's lightweight body and fuel-efficient engines linking cities out of the range of similarly sized aircraft.

Reaching that ambitious goal quickly now will be a challenge, according to government and industry officials, limiting the routes available to airlines just as Boeing boosts production to satisfy carriers that have waited years for their Dreamliners after a succession of delays.

Electrical issues, leaking fuel lines and a series of other malfunctions have caused a string of operational problems and emergency landings stretching back several months.

Regulators and airlines around the world, including the eight who fly the 787 today, will look to the FAA for guidance because the plane is built in the U.S. and the agency leads the certification of the new jet.

From its inception, the 787's advanced design, featuring weight-saving carbon-fiber composite materials and two fuel-efficient engines, was intended to make it suitable to fly practically any global route—crossing long stretches of ocean or spanning remote polar regions.

Chicago-based Boeing, by the middle of the past decade, had hoped that soon after introduction into service, safety regulators would allow 787s to fly up to 330 minutes, or 5½ hours, from the nearest emergency-landing strip.

When the first Dreamliner began carrying passengers in October 2011, 3½ years behind schedule, the FAA and overseas regulators permitted the jets to fly no longer than 180 minutes, or three hours, from any suitable airport. At the time, Boeing said it expected to extend that to 330 minutes by early 2012, citing work under way to modify some fuel-gauge software.

But FAA experts have been monitoring a variety of reliability issues that arose in the past few months and attracted attention inside and outside the agency, prompting FAA officials to adopt a go-slow approach in extending the three-hour restriction, according to people familiar with the matter.

The FAA's concerns, these people said, moved beyond the fuel-system-related software to include a range of power-supply issues along with questions about quality controls during Boeing's manufacturing process.

For now, Dreamliners remain under the 180-minute rule, a substantially tighter restriction than the FAA imposes on the Boeing 777, the 787's larger twin-engine sibling, which started flying in 1995 and is now offered with 330-minute certification only as of late-2011.The lead-up to the 787's original approval suggested both Boeing and the FAA believed the same factors would play out. Both Rolls-Royce and General Electric Co. engines offered on the Dreamliner were granted approved for 330-minute extended operations ahead of their first deliveries to their respective launch customers, All Nippon Airways Co. and Japan Airlines. During initial testing and certification, Boeing flew the 787 for 345 minutes on one engine, and five of six power generators disconnected, according to Mr. Sinnett.

That rules out airlines flying the 787 between, for example, Dallas and Sydney—a route Qantas Airways Ltd. now flies with the larger four-engine 747.

Continental Airlines, now part of United Continental Holdings Inc. and the U.S. launch customer for the 787, highlighted its hopes for the jet by naming Houston-Auckland as the first route for the plane. That plan has since been shelved for other reasons, but United has identified routes from the U.S. to Australia as another target market for its 787s, six of which are now flying.

A United spokeswoman said the airline doesn't comment on future route plans but said that it "looks forward to more opportunities to where we could fly" with the Dreamliner.

Mike Sinnett, a Boeing vice president and the 787's chief engineer, said Wednesday in a conference call the FAA wanted to take into account the early performance of the Dreamliner.

He called getting the 787 certified to be flown beyond 180 minutes "a procedural question." and said discussions with the FAA center on determining how early teething troubles are factored into the Dreamliner's certification to fly extended missions.

When the 777 was certified by the FAA years ago for extended overwater routes, the reliability of its engines was the primary consideration. The frequency of in-flight shutdowns was painstakingly tracked for each engine manufacturer, and those results largely determined when and which additional routes the planes would be permitted to fly.

But now, it turns out that some of the biggest concerns about the 787's reliability center on its redundant electrical grids, as well as the ability of batteries to power key onboard systems in case of an emergency requiring a lengthy diversion to a backup airport.

Rival plane maker Airbus, a unit of European Aeronautic Defence & Space Co. also hopes to be able to fly long routes far from suitable diversion airports. The European plane maker is developing its A350 XWB jet, itself delayed until 2014 after design issues, which aims to be able to operate as far as 350 minutes from emergency fields.

Achieving beyond-180-minute certification is also key for Boeing's next act: the larger 787-9, slated to be delivered in 2014 to launch customer Air New Zealand Ltd.

The Auckland-based carrier had already flagged that it wanted to fly ultra-long, overwater routes by pushing Boeing to certify the 777 to the full 330 minutes, allowing it to fly to parts of Africa and South America that that were previously impossible with a two-engine aircraft.

Air New Zealand spokeswoman Kelly Kilgour said, "It is simply too early for us to comment on the performance capability of the" Dreamliner.


www.wsj.com

http://seattletimes.com/html/businesstechnology/2020106573_787faa.html
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BeitragVerfasst am: Fr Jan 11, 2013 13:58:06 
Titel: wahrscheinlich kommt
Antworten mit Zitat

diese FAA Special Review, die Design aber auch Produktion und auch die Zulassungsmodalitäten von essentiellen Systemen bei der 787 betrifft, keinen Tag zu früh..

Die FAA wird laut Presseberichten die Review heute offiziell eröffnen.

Letzter Auslöser für die Sache war ganz sicher das Batteriefeuer da in Boston.

Die Review wird zwei Konsequenzen haben...

Das Flugzeug wird derzeit zumindest kurzfristig, so sich so ein Vorfall nicht wiederholen sollte, in der Li Ion Batt Konfiguration weiterfliegen können..

Die Alternative zur Review wäre ja ein Emergency AD gewesen, die wie beim CJ 4 ( C525C) damals 2011 einen Weiterbetrieb des Flugzeugs nur nach Retrofit mit konventionellen Batterien erlaubte.

Der CJ 4 ( C525C) ist noch dazu nach den weniger restriktiven FAR 23 ( in dem Fall der Communter Cat) Bauvorschriften zugelassen ( ein Umstand der in den vergangenen Jahre oft genug zu heftigen Kontroversen zwischen den US Behörden und der europäischen Behörden führte.)

Es gab allerdings auch für die C525C, sowie für die 787 eine Special Condition ( SC) für den Einbau der Li Ion Batts damals, und in denen wird nicht viel anderes drinnengstanden haben als für die 787.

Der Unterschied scheint zu sein, dass der CJ 4 doch eine konventionelles Flugzeug mit sehr konventioneller elektrischer Architektur ist, und der kurzfristig notwendige Ersatz des Li Ion Main Ship Accus durch eine NiCad oder Lead Acid sowohl physisch als auch von System relativ einfach war..

Bei der 787 dürfte der Fall insofern anders gelagert sein, als die Leistungscharakteristik der Li Ions ( Gemeinschaftsprodukt von Thales (Electrical System 787), YUASA als Zelllieferant und Securaplane als Chargerlieferant) offenbar von Anfang an als integraler Bestandteil so geplant war...

das heisst einen "schnellen" Ersatz der Li Ions für die 787, wird es weder Komponentenmässig noch was die Systemimplikationen betrifft gar nicht geben, was ein längeres komplettes Grounding der ganzen Flotte bedeuten würde..oder auch nur der Entzug bereits erteilter ETOPS Zulassungen würde die 787 de facto grounden, weil sie ja primär als Langstreckenflugzeug konzipiert ist..

Die Review wird sicher auch neben generellen Productionsnags und Qualitätsmängeln bei Bau und Ausführung einen Aspekt unter die Lupe nehmen, mit dem sich kein Mensch seit Jahren mehr in der Branche richtig wohlfühlt..

Dem Outsourcing von Engineering und Design bei so einem globalen Produkt wie der 787...

Da wird es sicher sowohl bei den Behörden als auch den Flugzeugherstellern, nicht nur bei Boeing, ein gewisses Soul Searching geben, ob das in der Form so gut war..und wenn nicht, wie man es verbessern kann, oder sogar ein wenig zurückfahren, damit Flugzeuge eines Herstellers wieder wie "aus einem Guss" nicht nur erscheinen sondern letztendlich auch funktionieren...

http://www.faa.gov/news/media_advisories/news_story.cfm?newsId=14214
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BeitragVerfasst am: Sa Jan 12, 2013 13:20:10 
Titel: naja......
Antworten mit Zitat

ist ein verzwickte Situation mit dieser FAA Review da....

Ist niemand wirklich glücklich damit, weder das DOT, noch die FAA, noch auch verständlicherweise Boeing...

http://www.youtube.com/watch?v=aeYSsEY6Eaw

http://online.wsj.com/article/SB10001424127887324081704578235370985104146.html?mod=WSJ_hp_us_mostpop_read

Im Transport Category Sector hat es in den USA wirklich schon lange keine "Review" mehr gegeben...ich glaub die letzte war vor 30 Jahren und betraf damals die DC-10 ( die hatte wirklich ein paar gröbere Designprobleme)

Und ob die derzeitige Situation bei den Problemen bei der Indienstellung der 787 wirklich eine generelle Review erfordern ist fraglich..

Die FAA stellt damit ja auch unter Umständen ihre Zulassungskompetenz in Frage, das Ding ist ja erst vor Kurzem von ihr zugelassen worden, und man darf annehmen, dass ein grosser Teil der Transport Category ( Part 25) Zulassungsspezialisten der FAA die letzten Jahre mit nichts anderem beschäftigt waren als der Typenzulassung für die 787...

Die ganzen "Snags" die es sicher gibt, da ein cracked Windshield, dort eventuell ein paar Oilleaks, die Sache mit der GE Engine wurde AD mässig abgeklärt und (offenbar) behoben...

Also airframeseitig und engineseitig sind das wirklich Sachen, die halt am Anfang wenn das Ding in den täglichen Betrieb geht, bei jedem Modell, jedes Herstellers, in gewissem Masse passieren..

Und wenn es da um Designprobleme geht, dann gibt es Service Bulletins und Mods mit denen Komponenten hard- oder softwaremässig verbessert werden...das gilt ganz sicher auch für die vielen elektrischen Komponenten, Generators und dazugehörige Software etc

Wenn, was sicher auch der Fall ist, ein Teil der Probleme damit zusammenhängt, dass der Hersteller halt derzeit massiv die Produktion hochfährt, und das läuft nie ganz rund, hat die Behörde auch andere Mittel als eine Review, um den Hersteller anzuhalten, da im Qualitätsbereich schneller Verbesserungen zu erzielen..

Nein, es scheint wirklich so zu sein, dass das einzige "brennnende" Problem der 787 die Batteriesache ist, und das Batteriefeuer da in Boston bei dem neuen JAL 787, naja, das ist einfach der Stoff aus dem ADs, also behördlich erzwungene Lufttüchtigkeitsanweisungen normalerweise gemacht sind..

Nur um einem solchen AD, das eben eine "unsafe situation" beseitigen soll, Folge leisten zu können, muss es Alternativen geben, respektive Lösungen, für den Hersteller..den Flugzeughersteller und den Batterienhersteller..

Aber es scheint so zu sein, dass man weder über Nacht den Li Ions, das Li Ion Batterien offenbar von Natur aus inherente Risiko ein Feuer auszulösen, abgewöhnen kann, auch nicht mit der kompliziertesten Chargertechnologie, die ja eingebaut ist und eben vom Design her dieses Risiko auf ein zualssungsmässig erträgliches minimieren soll, noch scheint es kurzfristig, wenn das so ist, möglich zu sein für Boeing die 787 zumindest temporär auf "konventionelle" Main Ship Batterietechnologie umrüsten zu können...

und ein "Containment" für die derzeitigen Batterien, das im Fall wenn so eine Batterie im Flug auf "china syndrome" macht, zu installieren, das diesen Namen verdient um grösseres Unheil vom Flieger abzuwenden im Flug, naja...da kann man gleich Bleibatterien einbauen, die sind dann noch gewichtsmässig viel leichter als so ein Containment, wenn so ein Containment überhaupt technisch möglich wäre, was ich auch bezweifle...

damit wäre aber, wenn in Reaktion auf das Batteriefeuer ein AD veröffentlichet worden wäre, der Flieger bis zur Lösung des Problems sicher gegrounded gewesen..

das wollte man offensichtlich nicht....

also irgendwie ein "halbe" G'schicht..

Flight Intl nennt den FAA Approach was die Review betrifft, "holistic"..

dabei müssten sie sich derzeit glaub ich wirklich nur die Batterie vornehmen...wär wahrscheinlich auch effizienter sowohl von Boeingseite als auch von der FAA die gesamte Brainpower auf das Battererietscherl zu fokussieren...für den Rest des Fliegers dürften die ganzen Regeln die in Kraft sind, was Zulassung, Design, Herstellung und Assembly betrifft, und die da notwenigen Produktverbesserungen ausreichen..



http://www.flightglobal.com/news/articles/faa-to-review-787-programme-380955/
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