Once the FAA has given it's sign off then Boeing will act aggressively to get the fix installed on the 50 787s that currently in customer hands. I would expect that there will be multiple Boeing teams at different locations working concurrently to do the retrofit which, as mentioned earlier, will take 4 to 5 days per airplane.
Much has been made that the root cause of the battery incidents has not been discovered and that Boeing and the FAA are rushing this. However, there is precedent for this type of actions since the evidence pointing to the root cause was probably destroyed. When TWA Flight 800 exploded of Long Island's South Shore there were many theories that abounded but the NTSB pinned the blame on fuel vapors in the center wing fuel tank that were ignited by a spark. There was no direct evidence of that but the result of their findings was that the FAA required some sort of fuel inerting systems to be retrofitted and that new aircraft designs have a an inerting system designed into the center wing fuel tank. All this on an aircraft accident that did not have a root cause. Here Boeing is taking action that would address any potential failures in the battery and severely mitigate the risk f a fire from ever happening by siphoning off any oxygen surrounding the battery.
Thus with its reputation out on the line, Boeing Commercial Airplane Head, Ray Conner and Chief Engineer, Mike Sinnett explained, in detail, Boeing's proposed solution and why they have confidence in it. The briefing in Tokyo was very technical in nature and very through. Here Boeing revealed that they expect that they can be done testing and start implementation of the fix in weeks and not in months. They qualified those remarks by stating that the FAA has the final say in lifting the airworthiness directive that lead to the grounding. One bit of news that is interesting is that Boeing will not lose the 180 ETOPS certification once the FAA has signed off on the fix. They still intend to achieve ETOPS 330 for the 787 though it is uncertain if the FAA will add any more tests for that certification because of the battery issues.
Boeing is rumored to already be producing parts for the retrofit on the 50 aircraft that are in customer hands as well as the 25 siting at Charleston and Everett as well as the aircraft that are in various stages of production. If Boeing can meet the schedule it has laid out to the FAA and get the testing done in weeks, I would expect the FA to take it's time in analyzing the data and perhaps ordering further tests. The 50 787s may not resume passenger flights for another 4 to 6 weeks (that includes the retrofit time). Deliveries probably will resume around the end of May but it ll depends on the FAA and how stringent they plan on being.
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17 comments:
Thanks for the updates.
Do you know if the retrofitting on planes already delivered will be performed at the customers site or will the planes will have to be flown back to Everett for the retrofitting?
Where ever the palne is that's where the work will be done.
Do they seriously think one test flight on one plane is enough to certify the changes?
I'd be amazed if this is enough. Having said that, I'm not sure what would be enough, or too much...
Oh, and thanks for the updates. Informative as ever.
The dertmination of how many flight tests and for how long is dependent on what you're testing. It would be a waste of time, money and reources to do more tests flights just for "publicity" or ptics sakes. Much of the testing is taking place on the ground (which is where the JAL fire took place) because there isn't a need to test the system in the air more than once. The FAA will determine if more tests flights are required or not.
It makes sense to do only one flight test as the battery system that is in question is used primarily on the ground and rarely in the air so why waste time, fuel, and other resources on flight tests.
Also according to Matt Cawby there are rumors that the SP-LRC flight test will occur on Tuesday
One theory floats the idea that the charging system has nominal spikes that may corrode the cellular structure through shorts or "faults" from electrical spikes from and to charging unit. One change is limiting the charging and discharging range so that no electrical inconsistency could occur, presenting an environment where the stability of the battery does not degrade, since only admitting a smooth exchange of power to and from the battery when charging and discharging. A robust effort secures its three level plan of Protect, mitigate known risks, and prevent propagation of heat and fire within the containment or the enclosure. So the "Package" is far reaching from manufacturing testing through to its installation of a safely contained battery.
The second theory is the airplane is not dependent on the battery for flight. Therefore, on the ground the battery is subject to its optimal power use, and is most vulnerable to overheating. Boeing has covered "in the event of" conditions whether flying or parked. The solution is retro fit with safer compartment, improved manufacturing testing and implementing guidelines and tighter parameters for power controls during operations. It would take about 6 teams to return one Airplane a day back into service. Or fifty days after the FAA certification is complete for a full fleet in service. Production models will matriculate as those teams return to the production floor.
Uresh, Andrew:
When testing something, you test it in as close to the real environment it will face as possible. That is hard to do on the ground, although not impossible (you have to reproduce changes in pressure, orientation, add typical vibrations etc). Otherwise it is not a full test.
The fact that the batteries are mainly being used on the ground is irrelevant as one of the incidents occurred during flight. Besides, the batteries can perform vital roles in flight. They are also charged in flight.
A quote from the Boeing website: "The main battery also provides backup power for critical systems during flight in the extremely unlikely event of a power failure. It is located in the forward electronics equipment (EE) bay, which is under the main cabin floor at the front of the airplane."
I simply cannot see how just one test flight is justifiable or will tell them anything useful especially when they have not root-caused the problem.
Re: David Cotton; Interesting observation on the flight test as you have stated, the main battery is interactive during the flight for priding power and charging. One flight suggest the problem was a ground problem only and one flight tests is just a validation for the new battery solutions and enclosure under operation. So the theory of ground only fault sounds like a Boeing's position on the battery problem. You indicated Boeing experience an in flight battery issue. This would require more in flight testing as you have suggested. Without knowing the root cause, Boeing uses a broad stroke of safety, saying no fire can occur during flight or on the ground using its current solutions, and a root cause is now irrelevant! A BOLD STEP BY BOEING! In Tokyo Boeing announced a happy resolution on the battery. One flight test is a big mystery worth pursuing an answer.
I thought the point of the flight test was to prove that during an "inflight" event fumes from the battery would not re-enter the aircraft or otherwise negatively impact the aircraft.
This test is not about proving the battery fixes, it is about proving the fix does not have a negative impact on the plane during an event.
One test flight seems on the light side to me too. On the other hand, I sometimes wonder if some people who post on this board aren't from over the Atlantic.
David true. However I said the main use is on the ground. I bet the FAA will force them to do a few more test flights though. Kevin I do not see though how and why Boeing would purposely overheat the battery to see the damage in flight, that is why it is done in the lab. TravelingMan I have flown many times on many aircraft since I lived in Jakarta for 4 years. What side of the Atlantic are we talking about though?
TravellingMan: I am from the UK, and have an intense interest in both Boeing and Airbus.
I want both to succeed. Airlines need two healthy and competitive planemakers - it pushes forward innovation and reduces prices.
I don't want any project to fail, and wish both companies the best. But I will criticise either planemaker - and have - when they muck up (the A380 and A440M debacles are occasions when I've commented on Airbus's woes elsewhere). Failure to place the companies under such scrutiny does not benefit anyone in the long run.
I stand by all the comments I've made on this blog, and believe I've been fair. It's just that as this is a 787 blog, it will mainly focus on any problems Boeing has.
Hi Uresh - you sure that LN 95 is out of the assembly line. Brendan's picture yesterday shows no aircraft in stall 106 (only the 3 HAI + 2 AI). Also if LN 95 had completed assembly in that time, it would have meant a significant step up in production from 28 day turns to 17 day turns since the last turn was on 6-Mar-13. Seems a bit fast!
Keep up the good work!
Cheers
A
Brendan told me that it is coming out around this time, should be out today.
Test flight in progress: LN86 / ZA272
http://flightaware.com/live/flight/BOE272
A preliminary report on the flight test today and more information on their plan go to: http://787updates.newairplane.com/787-Flight-Testing
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