Ethiopian Boeing 787 on fire at gate in London Heathrow

[Passenger]

Lets wait for the AAIB report! Tomorrow or a bit later. It will be a preliminary report. Hopefully the real source of the fire will be identified and the necessary corrective mesasures proposed (maybe including grounding).

There is already this "special report", issued today:

http://www.aaib.gov.uk/cms_resources.cf ... ET-AOP.pdf

[Flanker2]

Some facts:
The AAIB wants to see these ELTs removed immediately as they pose an immediate safety hazard, regardless of whether or not they were the source of this fire. So once the ELTs are removed, how will the aircraft fly without one?

The firefighters could not extinguish the fire with halon extinguishers. So what if something like this happens in flight? There is no water and foam in flight, and even if there were, it's dangerous to use water when there are powered electrical systems running all over the place that could create a very dangerous situation.
Was it due to the CFRP not reacting to halon or are there other materials involved? Is this problem a B7878 only problem or do other aircraft have this problem too? ie, is halon effective enough in fighting fires involving solid matters, ie furnishings, panels, structures?

The AAIB's troubling report clearly states that had this happened in flight, god only knows what the outcome would have been. Very lucky.

[KriVa]

The aircraft will fly just fine without the integrated ELT. In fact, they'll have to do what would happen on any other aircraft when the integrated ELT goes INOP: take along one or two more portable ELTs.
Secondly, as halon is heavier than air, fighting fires above your head tends to be quite difficult. Halon is a very effective way of extracting oxygen from a fire (which is one leg of the fire triangle), but it doesn't cool anything down. The moment the halon is dispersed away from the heat source, the fire will reignite.
A fire put out with Halon ALWAYS has to be cooled with water, or another non flammable material, liquid or not.
So even if the fire would have been put out with Halon alone, they still would have had to douse the heat source with water, especially when you have a battery in thermal runaway.

[RTM]

I'm totally not convinced that it was isolated to a small area, the images we've seen on TV are suggesting that the area affected by externial damage is quite significant. It's not a simple patch of 10x10 it's quite a large area that suffered damage enough to at least damage the paint and weaken the cfrp structure.

The fact that Boeings cfrp fuselage parts are moulded instead of traditionally bolted (like the "old" aluminium parts or even the cfrp panels of the A350) is a significant problem. You simply cannot "patch" a moulded fuselage like you would do with traditional fuselage. The fact that cfrp loses it's strenght when heated over 250°C is also something that you have to be considering, the large area seen on the tv images is an area that was heated well over 250°C and thus even without being burned through (although it's still not confirmed that the hull wasn't burned through, they specified "damaged composite structure" besides blackening and peeling paint. Damaged composite structure can mean everything, it can mean that it was burned through but at -least- it means that there is structural damage following a fire.) it still means that the structural integrity was breached due firedamage. Now you have a plane with a hull that has firedamage in an critical area of the plane where it will undergo a lot of stress during take off, landing and flight itself. But even then it doesn't stop... The fuselage was filled with smoke when the firedepartment entered the plane, smoke got denser when they got to the point where the fire was happening. This alone means that there is to be expected a significant amount of smokedamage, even soot damage... At this point the plane was also nicely covered with foam, I don't know which brand the LHR fire department uses but this can also cause significant damage though the modern types of foam are less damaging then the old ones which where really corrosive. So another point to take into account and then they started to tear up the interior of the plane to extinguish the fire in the crown of the plane, ok this probably won't have caused any extra damage but the fact they started to fight the fire with water (and maybe even used foam inside too, but this wasn't specified) meand that everything was covered nicely with water, all the electronics in that part of the plane (and especially below the floor) will have received a nice shower of water...

When you add everything it's not just a simple patch it's a lot more then most expect... Honnestly, I wouldn't be surprised for even a second if they announce that the plane is a write off... I actually expect it to be a write off and this mostly "thanks" to the Boeing design of using moulded fuselage parts... If the plane could have been repaired in a "normal way", thus by replacing panels, stringers, etc... I would say yes, they will repair it to have it back in service, but now? Maybe Boeing really wants to keep the 0 hull loss figure this early in the game and maybe they'll buy it from Wells Fargo to have it shipped to PAE to repair it there and keep it in the fleet as a testplane but I doubt it will fly with ET again...

I truly hope I will be wrong since it would be hard to see a hull loss that soon after EIS...

You'd be surprised how they fix an aircraft for a ferry flight...
Yes, I do agree that the damage is more extensive then it may seem. But also, it was in the top of the fuse, so most likely, the lower part is fine. Which will mean that the aircraft still is straight, and all that has to be done, is reinforce the roof section in that area to give it back its stiffness. If they have to bolt a couple of I beams to the structure to achieve that, then that is what they will do. It only has to do one unpressurized flight. Or maybe two, as the fuel burn will be quite significant at 10000 ft. But I am pretty sure it can be done. If not, the alternative is to take it apart, which I allready suggested earlier. But as more details emerge, I think it could fly.
As for the water and smoke damage. I am not really concearned about water. Aircraft are designed to disperse of water that accumulates in the fuse. The level reached will be hight then normal, but in this part of the fuselage there are generally no costly avionics. So that will be ok. The smoke, and interior damage... Yes, quite significant I think. I think it is a safe bet the interior will be mostly, if not all scrap. But that is easily replaced, I don't think the cost of the interior will tip the scale to a write off. Which is of coars also a possibility, a write off But I have a feeling that Boeing is not going to let that happen so quickly.

As for the ELT.
The statement from yesterday shows that it is the prime suspect. I honestly on't know why they only want them out of the 787... Sounds like a bit of head in the sand politics... But maybe the composite structure is more suseptable to overheating than traditional alloy. But I don't know, I would look further than the 787...

May be they are gearing up to that level for a later date. The thing is, if you take 6000 ELT's out of 6000 planes, you need 12000 back ups... Portable units are often carried double. So that will be an issue I guess... A hundred units for 50 787's, no problem, can be supplied from the shelf... But 6000 planes... Not really.

The fire extinguishers... Water extinguishers are carried on aircraft. I don't know if on all, but they are common. So I don't see why that should be a problem. The firefighting equipment on any aircraft is quite limited by the way. So if there is a fire on board, on any plane, you want to land as soon as possible. If the fire is big enough, it doesn't matter if the fuselage is made from alloy or composite, you have a big problem anyway.

[sn26567]

ELT inspections

Boeing sent out instructions to our 787 customers earlier this month giving them information on how to either inspect or remove the Honeywell Emergency Locator Transmitter (ELT) on their airplanes.

Today, Boeing is asking specific operators of 717, Next-Generation 737, 747-400, 767 and 777 airplanes to also inspect aircraft with the Honeywell fixed ELT. Boeing is taking this action following the U.K. Air Accidents Investigation Branch (AAIB) Special Bulletin, which recommended that airplane models with fixed Honeywell ELTs be inspected. The purpose of these inspections to is gather data to support potential rulemaking by regulators.

It is important to note that Honeywell ELTs have been deployed on approximately 20 aircraft models— including Boeing, Airbus and numerous business aviation aircraft.

Boeing will be working closely with customers in the coming days. As always, the safety of passengers and crew members who fly aboard Boeing airplanes is their highest priority.

After a Boeing blog, 29/07/2013

[sn26567]

ELT inspections

Boeing sent out instructions to our 787 customers earlier this month giving them information on how to either inspect or remove the Honeywell Emergency Locator Transmitter (ELT) on their airplanes.

Today, Boeing is asking specific operators of 717, Next-Generation 737, 747-400, 767 and 777 airplanes to also inspect aircraft with the Honeywell fixed ELT. Boeing is taking this action following the U.K. Air Accidents Investigation Branch (AAIB) Special Bulletin, which recommended that airplane models with fixed Honeywell ELTs be inspected. The purpose of these inspections to is gather data to support potential rulemaking by regulators.

It is important to note that Honeywell ELTs have been deployed on approximately 20 aircraft models— including Boeing, Airbus and numerous business aviation aircraft.

Boeing will be working closely with customers in the coming days. As always, the safety of passengers and crew members who fly aboard Boeing airplanes is their highest priority.

After a Boeing blog, 29/07/2013

Between 1,100 and 1,200 Boeing aircraft of all sizes have been fitted with the beacons, but Boeing is asking that airlines inspect as many as possible and report back within 10 days to help regulators decide what action to take, if any.

The FAA instructed airlines on Thursday to remove or inspect Honeywell fixed emergency beacons in the 787, but has not so far widened its mandatory checks to other models.

Airbus said it would carry out a review of the way the emergency beacons are installed onboard its planes, but it will not ask airlines to inspect them across their fleet, because no incidents have been recorded.

[Passenger]

Inspection for the ELT's is more then a recommendation now: Transport Canada has issued an airworthiness directive (manufacturer Honeywell is based in Canada, hence Transport Canada's involvement)

Bloomberg/Washington Post:
http://washpost.bloomberg.com/Story?doc ... 4TQIVR6BQJ

[RoMax]

Inspection for the ELT's is more then a recommendation now: Transport Canada has issued an airworthiness directive (manufacturer Honeywell is based in Canada, hence Transport Canada's involvement)

I mentionned this earlier this month in the topic of 787 news, but it's more recently that for example EASA also issued the same airworthiness directive. The respective ELT's are being used on 11 Boeing models, 7 of Airbus, the Dassault Falcon 7X and a civil version of the Lockheed Martin Hercules (in total more than 3,000 aircraft).
Some years ago Transport Canada already issued an AD for a certain type of Honeywell ELT's.

[Streetstream]

Any news on this one? Cause? And what happend to the 787. Is it a total loss?

[RoMax]

Any news on this one? Cause? And what happend to the 787. Is it a total loss?

Cause was already clear, a faulty emergency transmitter. The Canadian authorities, followed by FAA, EASA and many others requested immediate inspections on all aircraft using these transmitters (including several Boeing and Airbus types).

The respective aircraft is still waiting in LHR for repairs (its not a total loss, but a serious part of the rear section of the fuselage needs to be repared/replaced).

[Passenger]

Preparation for repairs has started :

[sn26567]

Boeing will repair the 787 Dreamliner jet damaged in a fire at Heathrow by making a duplicate fuselage section and cutting out a piece of it to create a giant patch, in a process one expert says is “pushing the limits of what’s been done in the past.”

A repair team will glue a giant composite plastic skin patch into the burned crown of the fuselage. Boeing has scheduled five weeks for the repair. It’s a very complicated procedure, but less so than the alternative option consisting of pulling out and replacing the entire aft fuselage section, which Boeing fabricates as a single-piece barrel.

Boeing’s one-piece barrel sections for the 787 are harder to fix than the structure Airbus has designed for the A350. Airbus fastens together composite panels to make the A350 fuselage, closer to the traditional structural design of a metal airplane.

Source and more details: http://seattletimes.com/html/businesste ... irxml.html

[sn26567]

Repair work in progress at LHR:


Picture Mark Kwiatkowski

Well hidden! Boeing doesn't want the world to know how its composites can be repaired on site...

You can also see that the tail has been removed in order to facilitate the repairs.

[jan_olieslagers]

I should think it is the tail section they are working on... which is an excellent reason for removing the empennage...

As for the "tent": don't I remember you are/were into chemistry? Composites require a controlled atmosphere for optimal curing, remember? Though I don't doubt the repairers will be quite happy to be out of view.

All that being said: thanks for sharing - and this repair looks like a masterwork of composite technology, well done, Mr. Boeing! (if it gets done and validated and approved, of course). Just hope there doesn't turn up another journo to call this "oplappen" as one VRT-professional did about poor OO-NAC...

[JAF737]

Repair work in progress at LHR:


Picture Mark Kwiatkowski

Well hidden! Boeing doesn't want the world to know how its composites can be repaired on site...

You can also see that the tail has been removed in order to facilitate the repairs.

Sorry, but what did you expect?
Technicians to work on composite material outdoors in LHR?

[Flanker2]

I thought that they were going to replace the entire barrel section? Why else remove the tail? There's little composite work involved if that's the case, it would be more about stabilising the aircraft so it doesn't tip over when the barrel section is removed, undoing the pipes, electrical cables and furnishings in that area, and bringing in a stand to remove the old section.

For major repairs, shelter from weather and cold is a requirement imposed by the aviation authorities. The fact alone that they didn't move it to a hangar after reinforcing the structure, says enough about the extent of the damage.

It will probably end up costing more than it's worth, or close to it. But for Boeing, it's a matter of prestige.

[flightlover]

I thought that they were going to replace the entire barrel section? Why else remove the tail? There's little composite work involved if that's the case, it would be more about stabilising the aircraft so it doesn't tip over when the barrel section is removed, undoing the pipes, electrical cables and furnishings in that area, and bringing in a stand to remove the old section.

For major repairs, shelter from weather and cold is a requirement imposed by the aviation authorities. The fact alone that they didn't move it to a hangar after reinforcing the structure, says enough about the extent of the damage.

It will probably end up costing more than it's worth, or close to it. But for Boeing, it's a matter of prestige.

The tipping of the plain is no worry in this case. They take weight off of the unsupported part of the plane. If it would have been the nose section, that would've been a whole other story.
All weight rests on the nose and main landing gear. Removing the tail section will just increase the weight on the nose wheels.

[Flanker2]

When you remove that tail section, the nose gear will be facing more force than it can bear.
You bet that it will tip over. We recently saw what a nose-first landing did to a Southwest B737. Removing a tail section weighing more than 20 tons at a huge length of arm from the center of gravity, I think that it will be unbearable for the nose gear and the fuselage section between the nose gear and the main gears.

It takes a small load put too soon into the aft cargo bay to make a plane "rotate". That tells us how little stress there normally is on the nose gear.

But to avoid such stresses, most major structural repairs are done while supported on several jacks along the fuselage, so the airplane will need to be supported well to avoid that it would tip over or kink, while supported on jacks.

So yes either way it can and will tip over if not well-supported.

The point is however, that the calculation of how best to support it will not involve any "composite repair work".

[appel]

How do you know how much force the NG can bear?
A nose first landing is not the same as removing part of the tail when you look at the loads on the nose wheel. Also it's not visible on the picture that there are no other supports for the aircraft except the nose gear.
In the comment of sn26567 from the 22nd of october you can read that Boeing will make a giant patch in stead of replacing the entire aft section. So unless they have changed their mind there will be composite repair work.

[sn26567]

The tail is back on the plane: