×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Fire on 787 during test. Any thoughts on cause?

Fire on 787 during test. Any thoughts on cause?

Fire on 787 during test. Any thoughts on cause?

(OP)
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?

RE: Fire on 787 during test. Any thoughts on cause?

A hit from a mystery missile?

RE: Fire on 787 during test. Any thoughts on cause?

(OP)
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.  

RE: Fire on 787 during test. Any thoughts on cause?

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: Eng-Tips.com Forum Policies

RE: Fire on 787 during test. Any thoughts on cause?

(OP)
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.  

RE: Fire on 787 during test. Any thoughts on cause?

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).  

RE: Fire on 787 during test. Any thoughts on cause?

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

RE: Fire on 787 during test. Any thoughts on cause?

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.

RE: Fire on 787 during test. Any thoughts on cause?

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.

RE: Fire on 787 during test. Any thoughts on cause?

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

Write that down.  winky smile

 

Mike Halloran
Pembroke Pines, FL, USA

RE: Fire on 787 during test. Any thoughts on cause?

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.

clown

RE: Fire on 787 during test. Any thoughts on cause?

(OP)
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)

RE: Fire on 787 during test. Any thoughts on cause?

Quote (hgldr):

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.

RE: Fire on 787 during test. Any thoughts on cause?

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

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

RE: Fire on 787 during test. Any thoughts on cause?

(OP)
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.  

RE: Fire on 787 during test. Any thoughts on cause?

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.

RE: Fire on 787 during test. Any thoughts on cause?

Weak imitation of the recent A380 Explosion and fire.

RE: Fire on 787 during test. Any thoughts on cause?

The description from the Seattle Times article:

http://seattletimes.nwsource.com/html/businesstechnology/2013409765_boeing12.html

seems to rule out flight test equipment. The contactors involved are production parts. So some analysis of the failure will have to be done to determine why it wasn't picked up by protection systems (overcurrent, differential protection, or arc fault detection).

Back to the drawing board.
 

RE: Fire on 787 during test. Any thoughts on cause?

More scary stuff: In reading through the pprune.org web site, someone posted a sumary of a similar 777 incident. In it, the AAIB (UKs version of the NTSB) made the following reccomendation:

"To implement differential current fault protection of main power contactors when designing future electrical systems"

Huh? Back in my days on the 767, 747, and 737 power systems, we had differential protection zones out to the primary load buss breakes and overlapping zones covering the GCB and BTBs. What happened? Did someone decide it was a good idea to eliminate it?

Arcing faults often do not reach overcurrent protection trip levels. As a result, faults can often persist for seconds, or minutes. Spraying molten metal all the while. Either differential or arc fault detaction schemes are the only reliable way to deal with such faults.

RE: Fire on 787 during test. Any thoughts on cause?

Latest theory - unsupported - is that a tool (probably metallic) was left in the electrical cabinent that burned and of course it touched some things it wasn't supposed to.

Always something dumb like that!!  I had my keys in my pocket with a couple of batteries I was taking to get replaced and sure enough - it got real hot and took me a second to figure out what the H#$$ll was going on...

I bet some mechanics are counting their tools!!

RE: Fire on 787 during test. Any thoughts on cause?

Isn't guess what the news is supposed to do, send someone to the airfield to get on camera and think of something to say?

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources