Fire on 787 during test. Any thoughts on cause? 1

[DHambley]

On Tuesday 11/09 the cabin of 787 #2 filled with smoke and flames were seen in an aft EE bay. Some instrument displays in the cockpit went out and some flight controls. The RAT system deployed.

Would anyone want to guess at the cause before Boeing tells the public?

 

[MintJulep]

A hit from a mystery missile?

 

[DHambley]

Wrong aswer but, that is kind of funny. The contrail from the airplane west of Los Angelos yesterday looked clearly like a contrail to me. I shook my head at all of the silly news reporters who were wondering where this "missile" had come from.

 

[IRstuff]

Are we even talking about the same video. The CBS video shows a plume rising at about a 60° angle from horizontal.

Not many commercial aircraft can do that and almost no aircraft could put out a contrail at sea level in 70°F weather.

TTFN

FAQ731-376

 

[DHambley]

IRStuff, That is the optical illusion which confused the news reporters. It "looks" like it is 60° from the horizon, but the contrail is not at the horizon. It is at a very high altitude.

 

[KENAT]

Maintenance guy was having a drag and dropped his butt just before take off. No time to search and wasn't going to admit to smoking.

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[PHovnanian]

Its possible that the fire originated in some flight test equipment installed for the certification program rather than production wiring.

But a fault in a load not being cleared by aircraft electrical protection systems progressing to the point that the RAT is deployed and avionics systems are affected is serious. Its possible that someone tied test equipment to a buss ahead of some branch circuit protection. If so, someone is losing a job. But if this reveals a problem in the electrical system design .... big trouble ahead (the 747-400 EPS fiasco comes to mind).

 

[MikeHalloran]

It could be something as stupid as the kerosene heater that Darryl Greenamyer forgot to secure, extinguish or remove before attempting to fly the B-29 he dug out of Greenland's ice.



Mike Halloran
Pembroke Pines, FL, USA

 

[KENAT]

Maybe squirrels or something chewed some wiring.

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[MintJulep]

Speaking of squirrels....

My club had a Grob glider that had been stored wings off over the winter. On it's first flight in the spring the PIC noted that he had to apply some aileron to keep the wings level, and commented on a peculiar odor.

Further investigation revealed that a squirrel had made a winter home inside the wing, but hadn't survived the winter.

 

[berkshire]

Mike, That was not a heater, that was a Honda generator secured with Bungee cords that were not adequate.
(As told to me by one of the guys on that aircraft.)
B.E.

 

[MikeHalloran]

Perhaps I mis-recalled what I read. It happens.

Write that down. ;-)



Mike Halloran
Pembroke Pines, FL, USA

 

[debodine]

Why are you talking squirrels when the OP clearly stated the RAT system was deployed? Did he say the SQUIRREL system deployed? Obviously RATS chewed through the wiring.

)

 

[DHambley]

Latest news is that a faulty "control panel" was at fault. I'm thinking that it could have been the huge Hamilton Sundstrand ECBU panel. (ECBU = elecronic circuit breaker unit)
Any more thoughts? (other than squirrels and missiles)

 

[PHovnanian]

Latest news is that a faulty "control panel" was at fault.

Link to the story?

Second (or third) hand information isn't worth much, particularly when it has been filtered through non-technical news staffs. I'd tend to believe Av Week a bit more than the local talking heads.

 

[KENAT]

I'd be tempted to wait and see what the accident investigation reveals.

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[MiketheEngineer]

Something overheated for some reason and caught fire - or almost did.

Until we find out why and what - it is all conjecture.

 

[DHambley]

Boy oh boy. The Seattle Times today reported that they had photos of the Hamilton Sundstrand P100 panel showing the charring. They aren't releasing the photos per Boeings request. A re-design and re-certification of these power control panels is not going to be a trivial task. Looks to me like it could turn out to be another big delay for the 787.

 

[dgallup]

Boeing says: "We have determined that a failure in the P100 panel led to a fire involving an insulation blanket. The insulation self-extinguished once the fault in the P100 panel cleared. The P100 panel on ZA002 has been removed and a replacement unit is being shipped to Laredo. The insulation material near the unit also has been removed."

Further complicating ZA002's return to testing is the damage sustained during the fire, which included dripping of molten metal onto the system wiring and internal fuselage structure, which program sources say is driving Boeing's inspection of the area surrounding the P100 panel to "determine if other repairs will be necessary."

"As part of our investigation," says Boeing, "We will conduct a detailed inspection of the panel and insulation material to determine if they enhance our understanding of the incident."

"In addition, we are determining the appropriate steps required to return the rest of the flight test fleet to flying status."

Boeing is continuing to investigate the fire and determine any impact to "the overall program schedule" as it reviews data collected from the incident.

 

[moon161]

Weak imitation of the recent A380 Explosion and fire.