Heathrow closed after plane fire (Dreamliner)

Just adding some information to things I have already posted.

reply to post by C0bzz


It appears that Ethiopian (ET) aircraft do not have a crew rest area there.

ET have also said someone saw sparks coming from equipment related to a air conditioning unit, but apparently there isn't any air conditioning equipment near the burn marks.

Boeing also employed a brute force approach to solving the battery problems, which included putting a steel box around the battery and a vent. The closest battery is also located just aft of the wing box, so it seems unlikely that it was a battery problem.

reply to post by C0bzz


The burn marks however were located approximately above the galley. The galley would also include power distribution equipment (electrical energy conversion - inverters - SMPS?) due to the electrical architecture of the 787. Some of the wiring to distribute power apparently runs across the ceiling.

Latest update on the BBC.

The UK's Air Accidents Investigation Branch said the initial investigation was likely to take several days. It said it had found "extensive heat damage in the upper portion of the rear fuselage, a complex part of the aircraft". "However, it is clear that this heat damage is remote from the area in which the aircraft main and APU (Auxiliary Power Unit) batteries are located and at this stage there is no evidence of a direct causal relationship."

www.bbc.co.uk...

BBC news says fire not linked to battery so says air accident investigators

Originally posted by Zaphod58
reply to post by solidshot

 

It's possible this is an APU issue too. They recently said that the APU was overheating as well. It's located in the rear near the batteries.

Didn't the batteries on the dreamliner have issues as well? Didn't they catch fire?

Why would the put them near the APU?

Also what Make and model is the APU on the dream liner?

I'd look for it myself, but I am busy.

reply to post by projectvxn


The batteries are both located in the lower fuselage, well below where the fire damage occurred. There is an APU fuel line, a power junction box, and a galley in the area near where this fire occurred.

It uses the Hamilton Sunstrand APS 5000 APU system.

reply to post by Zaphod58


Do we know if that particular APU has a decent service record? Or could it have a fuel line problem? I hate to make you speculate on the matter. But you do know quite a bit about this bird.

reply to post by projectvxn


The chances are that it wasn't a fuel leak, based on the timing of the fire. The plane had been on the ground for something like 8 1/2 hours prior to the fire.

The APS5000 is 787 specific, but Hamilton Sundstrand has supplied APU units for a variety of aircraft in the past, and all of them have a good service record. They supply APU units for everything from the single aisle Airbus family, the 717, 737, BAe 146, Dash-8 100-400, V-22, various helicopters, ERJ 135/140/145, as well as cooling systems for military and civilian aircraft.

A report today from the AAIB says that someone saw sparks, but no fire from a junction box dealing with the air condition system. It'll take a few days before they can say for certain where the fire started, but it appears that it may be a one off condition.

This has just popped up on Twitter from the Wall St Journal.

@WSJ Breaking: Investigators are probing Boeing 787's emergency locator transmitter as a potential cause in Heathrow fire

Obviously no doubt a relief for Boeing that it wasn't another battery issue, although any problem that causes a fire still isn't great.

reply to post by solidshot


We had a WC-135 come through, after we parked it, the ELT launched. Put a new one in, it launched, replaced a sensor and the ELT and it launched. No design issue, just some bad sensors and wiring. Probably the needy outcome for Boeing as it's almost definitely a one off problem.

Honeywell has joined the investigation into the ELT.

"Our ELT products have been certified by the [US Federal Aviation Administration] since 2005, are used on a number of aircraft models, and we've not seen nor experienced a single reported issue on this product line," the company adds.

Honeywell also supplies the emergency lighting system, terrain awareness warning system, navigation system and nacelle anti-ice regulators on the 787. But only the ELTs are known to be situated in the area immediately proximate to what Honeywell describes as damage from a "fire".

www.flightglobal.com...

It appears that a short in the ELT led to the fire. The AAIB is recommending action.

The AAIB statement said: "Detailed examination of the ELT has show some indications of disruption to the battery cells. It is not clear however whether the combustion in the area of the ELT was initiated by a release of energy within the batteries or by an external mechanism such as an electrical short."

As the ceiling space where the ELT is located "do not typically carry the means of fire detection... had this event occurred in flight it could pose a significant safety concern and raise challenges for the cabin crew in tackling the resulting fire."

www.bbc.co.uk...

reply to post by Zaphod58


About 30 minutes ago a JAL 787 en rout from Boston to Tokyo made a u-turn over Canada, anyone know what the issue is there?

reply to post by waynos


Maintenance indicator in the cockpit. No word on what though.

reply to post by Zaphod58


Can't help feeling that each incident like this has Boeing more twitchy than they normally would be, and lots of silly grins in Toulouse, so far.

reply to post by waynos


Probably, but remember the Trip Seven had a pretty bad start too and look where it's ended up. It just needs time for all the new technologies to mature a little more.

The AAIB is calling for the FAA to order the immediate shut off of Honeywell ELTs on 787s, until appropriate airworthiness actions can be taken. Honeywell has produced the RESCU 406 (the ELT on the 787) in 2005, and operates them on multiple aircraft. There are currently around 6,000 units in use, and Honeywell says this is the first thermal event they have ever seen. Honeywell and Boeing both support the recommendation.

The U.K. Air Accidents Investigation Branch (AAIB) is asking the FAA to turn off the Honeywell emergency locator transmitters (ELTs) in all Boeing 787s “until appropriate airworthiness actions can be completed.”

The action comes as the AAIB continues to investigate a July 12 “fire event” onboard an Ethiopian Airlines 787-8 that was unoccupied and unpowered on Stand 592 at London Heathrow Airport.

“The initial technical investigation confirmed extensive heat damage in the upper portion of the rear fuselage, with significant thermal effects on aircraft insulation and structure,” says the AAIB in a special bulletin released today.

Investigators determined that the most severe heat damage and highest temperatures were close to the crown of the fuselage on the left side of the aircraft, which coincides with the location of the aircraft’s ELT and its wiring that is mounted internally on structure close to the aircraft skin.

Source

The AAIB is looking at a pinched wire in the ELT, that appears to have happened during the initial build rather than installation in the aircraft.

Not seen any info anywhere else yet but this just popped up on twitter.

@Bruciebabe Quatar Aitways B787 smoke incident in Doha (A7-BCB). Unconfirmed reports say smoke from the rear equipment bay. APU

:EDIT:Mentioned here as well.

www.pprune.org...

Smoke out of a panel is fairly minor, but since it's the Dreamliner, it'll be blown out of proportion I'm sure. That could have been anything from an actual short, to some oil or something on a wire rolling into a junction box.

Great article about the repair process over at AvWeek. Insiders are saying the skin held up really well to the fire, which is estimated to have reached 1,000-1,200 degrees based on damage to the paint, but apparently didn't burn through the skin itself.

It's thought that Boeing will place a bonded patch over the damaged area, which would include stiffeners that are already in the skin of the aircraft, and then fly it either to Everett, or another facility that has the equipment needed to repair the aircraft permanently. It's not sure whether they'll cut out the damaged area, and replace it, or have to put in a new plug yet. They most likely will do an NDI inspection using hand held equipment to determine if there are any cracks or unexpected damage in the surrounding area before the flight.

I think that if this repair goes easily, and as well as hoped, it will go a long way towards restoring faith in the plane, and in Boeing. Major repairs have always been one of the fears with the Dreamliner because of the composites.

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