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-   -   Ethiopean 787 fire at Heathrow (https://www.pprune.org/engineers-technicians/518971-ethiopean-787-fire-heathrow.html)

BOAC 17th July 2013 16:05


There may be an argument now to give them more resources so as to keep at least 1 runway open during 2 fire incidents
- anyone able to post the assets at LHR? Was extinguishant discharged at the PIA incident?

JW411 17th July 2013 16:19

So what happens to those aircraft who have creatively "committed to Heathrow" due to a shortage of fuel (on the basis that Heathrow has two runways and the weather is reasonable) when both runways suddenly shut?

Do they land at Heathrow without fire cover or do they now demand priority over everyone else who is diverting at the same time?

I would not like to be in that situation.

You could end up in deep !!!!! just because a coffee cup or an ELT has caught fire in a Boeing 787 on a remote stand at Heathrow.

funfly 17th July 2013 16:23

I had a lovely glass fibre aircraft once...



http://www.funfly.co.uk/images/KISS.jpg

FF

JW411 17th July 2013 16:26

Well, the rudder looks OK!

tilnextime 17th July 2013 16:27


So what happens to those aircraft who have creatively "committed to Heathrow" due to a shortage of fuel (on the basis that Heathrow has two runways and the weather is reasonable) when both runways suddenly shut?

Do they land at Heathrow without fire cover or do they now demand priority over everyone else who is diverting at the same time?
That's what the Pre-Accident Plan sets into motion - ATC knows the given airport is closed to traffic and executes the established plan to divert flights to nearby (and there are several in the London area) airports. It's the controllers' job to sort out fuel issues. If a pilot failed to adequately plan his fuel, or if winds were greater than forecast, ATC will assist as necessary. In fact, ATC will begin diverting aircraft long before they are "committed" to make room for those that are already committed.

Again, there are sentient life forms in abundance beyond the wing tips, no less the cockpit.

BOAC 17th July 2013 16:36

JW - I guess the "intelligent life forms out there beyond the wing tips." would have allowed the 2/3 short final traffic to land and thrown the rest off on Maydays.

JW411 17th July 2013 16:47

My guess also.

I am eternally grateful that I always worked for an employer who always allowed me to carry a sensible amount of fuel.

Lonewolf_50 17th July 2013 17:27


I am eternally grateful that I always worked for an employer who always allowed me to carry a sensible amount of fuel.
As bean counters (try to) micromanage that more in the future (and why should anyone believe otherwise, given trends to date?) one can see the misgivings in your post manifest themselves into some difficult realities for more than a few flight deck crews. :suspect:

One's best self defense is to stay well ahead of the aircraft and the flight/mission so that when these things crop up, there is an out.

Best wishes to all on that score. The "interesting times" are arriving sooner and sooner. :cool:

Look_Up 17th July 2013 20:47


Just out of interest: What was the PIA incident that was ongoing at the same time?
I was a passenger on an Iberia/Vueling flight that had pushed back at around 1630. Before taxying, at about 1640 the captain shut down the engines and announced we were delayed by an aircraft that had just landed and had one (or was it two) burst tyres ahead of us. I presume this was the PIA incident. We were delayed by about 80 minutes in total when the 787 incident came on top of that and we saw the aircraft in question on taxi for takeoff.

speedtapeking 18th July 2013 00:04

Sure this thread is titled "Ethiopian 787 fire" can we keep it to that? I really don't care what people think over whether the place should of been kept open or closed, I just want to find out about the fire on said aircraft not the ins and outs of what the airport did !

RodH 18th July 2013 00:34

Why the delay ?
 
It seems to be taking a very long time to find out the root cause of this fire.
Six days seems to be unusually long and If past history of aircraft fires is anything to judge by it seems to normally only take a few days to find out the cause.
Given the past history of the B787 one would think an answer would be forthcoming ASAP.

RCav8or 18th July 2013 00:52

The latest news says that the AAIB will issue a preliminary report in the next couple of days. Until then Boeing can say very little, except that the the LiOn batteries are in no way involved, which was pretty obvious from the beginning.
An interesting side note was Honeywell's willingness to remove the ELT's, if they are asked to. Can a commercial aircraft legally operate without an ELT?

LASJayhawk 18th July 2013 00:57

"Story" on possible removing of the ELT's

Honeywell says would remove 787 beacons if asked as fire probed

archae86 18th July 2013 01:04

WSJ comments
 
A newish Wall Street Journal online story which leads with the assertion that an AAIB interim report is expected soon goes into some ELT detail--including a strong suggestion that someone thinks a possible ELT role in the cause likely enough to consider a possible recommendation for temporary removal of them from 787s.

Regarding the legalities of ELT-free operation, the WSJ article asserts that while they are required on planes to be used for passenger flights in the US, it is allowed to continue operation with them inoperative for as long a 90(!) days before replacement or repair, and further asserts that no case of ELT actually being useful in a large airliner incident has been recorded in the last couple of decades. It asserts that European rules are similar to the US rules.

Lastly, and not in the WSJ article, I learned that this ELT battery is far larger than I might have thought. I've lost the reference, but believe that for this Honeywell model the battery weight was given as a bit over six pounds. If true, that is plenty of energy to serve as a major ignition source if something goes seriously wrong.

[edit: another poster has cast very serious doubt on this battery weight claim. I know I saw it written, but it surprised me. Most likely it was false--possibly by misconstruing the entire ELT weight as being the battery weight]

LASJayhawk 18th July 2013 01:21

The ELT + Battery is 6.6 Lbs.

A wag would be about 2 Lbs for the battery itself.

ETA: on an Artex C-406 the battery pack is about 1 Lb, and the whole thing, ELT + Tray + Battery is 4 Lbs 11 oz.

ironbutt57 18th July 2013 02:14

Many aircraft have portable ELT's vs "installed" ones...

Buster the Bear 18th July 2013 03:10

Having just experienced the Dream Maker and the Thomson Premier Club product to Orlando, all I can say as a passenger is WOW!

My vacuum is noisier than a full load departure compared from the forward cabin and the pressurisation meant that after a nine hour flight we arrived amazingly refreshed!

For me, this aeroplane is frankly brilliant. No smoke, no fires and no drama! Loved the HUD for the crew!

Thomson have it 100% commercially aligned with the market. Premium it certainly is!

LeadSled 18th July 2013 03:28


ELTs, whether fixed or portable (and most “fixed” ELT can, if accessible, be un-clipped and used as a portable) which conform to TSO C-126, can and most do have an inbuilt GPS chip.
It will be a very interesting situation if the fire was cause by a fixed ELT.
Extensive Australian research has shown that fixed ELT are an expensive waste of money, as the failure rate in service (failure to broadcast a signal after an accident, or broadcasting a signal when they shouldn’t) is worse than 90%, and 100% in water.
If this fire is caused by the the ELT, the answer is to get rid of them, and rely on the portables contained in or adjacent to the slide-rafts, the type shown in the illustration.
The “mandatory” fitting of fixed ELTs resulted from political pressure in the US, after a well known politician was killed in Alaska. No cost/benefit analysis was ever carried out.
ICAO picked up the FAA rule, again without detailed consideration.
The Australian research could find no case where a fixed ELT in an airline aircraft had worked after an accident, including accidents where the tail of the aircraft was substantially intact.
Folks,
The above is a reader comment from the Australian blog, "Plane Talking", run by Ben Sandilands, a well known and highly respected transport journalist.
Australian aviation regulations are generally consistent with these finding.
After the Australian rules (dropping mandatory fixed ELT) were put in place in about 1997, a five year post implementation review was carried out by CASA Australia, and the ongoing failure rates of fixed ELT was confirmed, as was the very low failure rates of portables in survivable accidents.
All in all, fixed ELT have proved to be a very expensive waste of money --- and all brought about by a knee-jerk political reaction to a single GA accident in Alaska.

PS: As to what FAA require in US airspace, I would suggest some who have made definitive statements might re-consider.
For any foreign carrier on a FAR 129 Certificate/Operations Specification, it is all in the detail, and unless there has been a major change in recent times, quite a number of foreign carriers, who normally only carry a number of portables, usually attached to the slide-rafts, have not had to fit useless fixed ELT to operate in US airspace.

olasek 18th July 2013 07:06


It seems to be taking a very long time to find out the root cause of this fire. Six days seems to be unusually long and
Fire/incendiary investigations often can be the toughest to crack specially if one looks for a 'root cause'. Six days is absolutely nothing. I would argue that a 'root cause' of TWA800 fire/explosion was never found - only the best theory was adopted after years of futile attempts trying to reproduce events. Did they ever find root cause of the 787 batteries fires/failures - NO. I wouldn't be surprised if the preliminary report in this case will offer temporary recommendations and investigation will continue.

Pittsextra 18th July 2013 09:13

At what point does co-incidence in tandem with the lack of understanding with the prior electrical issues fail to provide comfort for the FAA/CAA/EASA?

mbriscoe 18th July 2013 09:17


So you think they should be able to respond to to 3 worst case scenarios simultaneously? Because all fires are treated equally. I'm sure we all know how quickly a fire on board an aircraft full of fuel can escalate, especially when you add in hazardous materials like Lithium and Carbon Fibre

I think you MAY have a point. I assume each fire station in LHR is responsible for 1 runway and the gates/terminals/hangars are assigned to whichever station is closest?

When was the last time LHR had 2 fires at the same time? I also wonder how long it takes to turn around the airport fire vehicles after they have discharged their foam and get them ready to roll again
If the fire cover was increased to be able to handle three, four ... incidents then apart from the huge increase in costs then I can imagine the comments in the media if there was a serious incident involving loss of life and there was a whole fleet of fire appliances sitting in the fire station. They would probably ask why the airport had not been closed to make them available.

Rather than each fire station being responsible for a different runway, I wonder if there are two separate ones to protect against a worse case scenario where an aircraft hit the fire station and disabled the whole fleet?

They might not often have two serious fires simultaneously but they have to allow for training where one fleet of the fire appliances might be involved in training with a dummy fire so could have emptied their tanks of at least the water.

Hockham Admiral 18th July 2013 09:27

HMFC, JW? ;)

Saint-Ex 18th July 2013 11:58

Slightly off the subject but, according to the Daily Mail, I see the 787 holds up to 800 passengers!

Volume 18th July 2013 13:03


Fire/incendiary investigations often can be the toughest to crack specially if one looks for a 'root cause'. Six days is absolutely nothing.
I fully agree if the aircraft lies scattered in million pieces on the ocean floor. But if it sits in one piece on the ramp with localized fire damage and fully accessible, I would expect a more informative press release by now.

JW411 18th July 2013 13:09

Hockham Admiral:

HMFC; yes (and all of the seven airlines that I susequently flew for).

lomapaseo 18th July 2013 13:49


But if it sits in one piece on the ramp with localized fire damage and fully accessible, I would expect a more informative press release by now.
Localized damage :confused:

Then why do we have so many posters suggesting that it's unrepairable ?

I wonder where the coffee pot problem came from then?

certainly by now if it were localized PPrune posters would have already solved it.

Pittsextra 18th July 2013 15:02

Boeing 787 Probe Spurs Honeywell Beacon Shutdown, Lithium Checks
By Robert Wall


July 18 (Bloomberg) -- U.K. authorities probing last week’s fire on a Boeing Co. 787 at Heathrow airport said a Honeywell International Inc. beacon installed close to the site of the blaze should be deactivated on all other Dreamliners.
Britain’s Air Accidents Investigation Branch said in a special bulletin that the U.S. Federal Aviation Administration should also lead a safety review into lithium battery-powered transmitters on other aircraft models.
Shutting off the Emergency Locator Transmitter system on the Boeing jet is a precautionary measure “until appropriate airworthiness actions can be completed,” the AAIB said.
The July 12 incident on a Ethiopian Airlines Enterprise Dreamliner was the most-serious setback for Boeing’s marquee jet since regulators ordered the global 787 fleet idled for three months following fires linked to lithium-ion batteries. The AAIB hasn’t called for a grounding following the Heathrow event.
“Had this event occurred in flight it could pose a significant concern and raise challenges for the cabin crew in tackling the resulting fire,” the AAIB said today. “The ELT has shown some indications of disruption to the battery cell.”
Overheating of emergency transmitters “is extremely rare” and last week’s incident was the first affecting the Honeywell system, the safety body said.
Smoke Spotted
The AAIB probe, which included Boeing, the airline, and U.S. safety representatives, was broadened to include Honeywell after the beacon made by the Morris Township, New Jersey-based company was isolated as a potential cause of the fire.
The ELTs rely on chemical batteries made of lithium-manganese dioxide to power the beacon even if the plane’s electrical system fails.
Air traffic control personnel spotted smoke coming from the Ethiopian jet, parked and not under power, at 4:34 p.m. local time, with emergency personnel arriving a minute later to extinguish the fire, according to today’s bulletin.
Fire fighters using breathing equipment entered the plane and initially failed to suppress the blaze using Halon devices. They then removed ceiling panels and applied water.
The plane suffered “extensive heat damage” in the rear, including to its composite-plastic fuselage, the AAIB said. The ELT is the only aircraft system in the area, it said. Flight crew had not reported any technical problems with the plane.
Other Dreamliner users from ANA Holdings Inc., the first to operate the jet, to United Airlines, the world’s largest carrier, have maintained 787 services. Ethiopian Airlines has also continued to operate its three other planes.
Boeing had delivered 66 Dreamliners to 11 airlines and a leasing company through June. The Chicago-based planemaker has booked 930 firm orders for the jet, which has a list price of $206.8 million in its cheapest version.

Pittsextra 18th July 2013 15:07

Air Accidents Investigation: S5/2013 - Boeing 787, ET-AOP

DarrenWheeler 18th July 2013 15:07

AAIB bulletin has now been released.

Air Accidents Investigation: S5/2013 - Boeing 787, ET-AOP

"A fire event occurred on a parked, unoccupied and electrically un-powered Boeing 787 aircraft at London Heathrow Airport. Subsequent examination of the fire-affected area has focussed on the Emergency Locator Transmitter (ELT). Two Safety Recommendations have been made."

tubby linton 18th July 2013 15:18

The alarming thing for me , and it is stated on the final page of the AAIB's reort is that if the ELT battery is at fault there remains the possibility that this failure could have occurred in flight in a fuselage zone with restricted access and no local fire surpression or detection.

MurphyWasRight 18th July 2013 15:26

Interesting bit from the report (often what is chosen to include in a preliminary report can be revealing):


The ground handling agent accordingly turned
off ground power at the stand’s control box but left the
power umbilical cables attached. The engineer visually
confirmed on the flight deck that ground power was no
longer available.
Given prior "sneak paths" in the electrical system one wonders if having the cable connected but unpowered resulted in an unforseen circuit.

I have no idea exactly what turning off the power at the stand does, all conductors disconnected, all grounded or some other configuration.

Does sound liket the ELT is involved though, of course there is still the chicken and egg question. (Which came first)

Think about that long enough and you end up with a chicken ommellete...

Ian W 18th July 2013 15:31

In view of LeadSled's earlier post about Australian findings on ELTs, the permanent removal of fixed ELTs would appear to be the most appropriate action.

DarrenWheeler 18th July 2013 15:35

The report also says there over 6000 of this version of ELT's out there fitted to a variety of aircraft, with this being the only significant thermal event.

Is this just a case of bad luck of a faulty unit being fitted to a 787?

EEngr 18th July 2013 15:36

What is the service history of the Honeywell unit? Any other experience with these things bursting into flames?

On a related note: What sort of connections does the ELT have with the aircraft power system? There is a flight deck test switch plus activation annunciation. Is this powered from the aircraft DC system? Any chance that it was connected to a 32 Vdc buss (most other applications are likely to be 28 Vdc).

Self Loading Freight 18th July 2013 15:45

Another case where -- assuming that the initial findings are correct - it's not clear whether the underlying fault was in the battery or the circuitry to which it was connected. Is anyone familiar enough with the ELT circuit to know whether the battery is fused?

High energy battery circuits are supposed to have some form of thermal or electrical cut-out that trips before enough energy has been delivered to start a fire. So, once again, there are two failures to explain: whatever it was that caused the bake-off, and whatever it was that was supposed to stop that happening but didn't.

Interesting that the recommendation to remove the ELT was restricted to 787 carriers. If this is a common part across types, is this an indication that the 787 is uniquely vulnerable?

Pittsextra 18th July 2013 16:09


What is the service history of the Honeywell unit? Any other experience with these things bursting into flames?

The AAIB report says there are 6000 units in a variety of aircraft and to date this is the only thermal event.

fenland787 18th July 2013 16:12

From the BBC "The AAIB said the problem might not be confined to the 787 and recommended that regulators conduct a safety review of similar components in other aircraft."

Does anyone know if there a reason they would have to say that (rather that "turn them all off now") for types other than the one they are investigating? I can't think of one unless they suspect some 'unfortunate' interaction between an ELT battery issue and the 787 systems that wouldn't affect other aircraft types?

MurphyWasRight 18th July 2013 16:20


Does anyone know if there a reason they would have to say that (rather that "turn them all off now") for types other than the one they are investigating? I can't think of one unless they suspect some 'unfortunate' interaction between an ELT battery issue and the 787 systems that wouldn't affect other aircraft types?
For 787 case it is already clear that "bad things" can happen if the ELT gets hot.

For others types it is an open question if the same scale event would have breached the hull. Still not something that one would want in flight though.

Also on protection of battery by fuse, from the spec sheet the unit is rated at 5W at 406Mhz, plus lesser at the lower frequencies.
This translates to expected power in use in the 8 to 12 watt range, plenty to get a wire hot enough to cause trouble.
Could be higher, 8 watts would actually be very impressive effeciency figure.

LASJayhawk 18th July 2013 16:30

Only way to make the ELT inert is to pull the battery pack out.

Artex uses ship power for the light in the cockpit, not sure about Honeywell.

There should be no direct, or even indirect, path between the ship power and the ELT battery pack.

Looking at an Artex pack, I can see a potential failure mode that would short a cell out. I have no reason to think Honeywell's execution of a battery pack would be much different.

If I'm thinking what the AAIB is thinking, were all gonna be pulling ELT's out of everything.

ETA: Self Loading Freight. on the Artex battery pack, it goes straight two 2 fuses in the pack itself.

Lonewolf_50 18th July 2013 16:35

Maybe the Aussies have it right, and the requirements were not well substantiated in the first place, particularly for long haul airliners who tend to fly under radar control or under well established flight routes.

The GA event presented as the trigger hardly fits the "we know where it is or will be" model of an airline flight. I can see how an ELT is a good idea when you fly in out of the way areas, or typically in uncontrolled airspace.

I'd be interested to hear what people in the SAR community, civil and military, think about ELT's as an aid to their making first contact with a downed aircraft.


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