BA 777 on fire in Las Vegas

[Jetstream67]

I think that fail-safe might be a more productive route for turbines -- Think how car windscreens have evolved from big lethal broken shards through regularly shaped small bits to the current 'broken but still hanging together' approach

[bateleur]

In reply to iomapaseo:

I see no signs of shrapnel damage. As some said much earlier in this thread it doesn't look like an uncontained disk rotor. Nor do I see signs of extreme pressure release (some call this an explosion). Instead the pictures of the externals of the engine pod and wing go hand in hand with a persistent ground pool fire.

If you watch the video, the first thing the fire appliances do is direct their jets on to the ground beneath the wing.

[Scuffers]

I think that fail-safe might be a more productive route for turbines -- Think how car windscreens have evolved from big lethal broken shards through regularly shaped small bits to the current 'broken but still hanging together' approach

If you're suggesting that the engine casing should be able to retain any parts from a broken turbine breaking out, that's simply not feasible.

the speed/energy in these parts (especially at take-off power) is simply staggering, you would need something like several inches of Chobham armour backed with heavy armour plate.

[Avionista]

If it is missing it means it was irrelevant, namely design wasn't in question rather perhaps the flaw in manufacturing of random nature.

If the problem is a manufacturing flaw in a small number of HP turbofans, why does the AD require repetitive inspections, ad infinitum. Surely, the replacement of any components found to be defective would suffice. The FAA, perhaps, believes the problem could develop over time in any of these HP turbofans, hence their requirement for repeated EFI/ECI scans.

I agree that nothing man-made is ever 100% reliable, but vital components should strive for a MTBF well in excess of their expected lifecycle.

[funfly]

If you're suggesting that the engine casing should be able to retain any parts from a broken turbine breaking out, that's simply not feasible.

I recall video footage of the testing of RR engines where this very feature is demonstrated as a test that the engine has to pass before certification.

[porterhouse]

but vital components should strive for a MTBF well in excess of their expected lifecycle.

Yes, they do strive and there is no data that would indicate this doesn't apply to this part as well. Reliability of these engines is phenomenal by any standards and this includes MTBF.

[flyingchanges]

I recall video footage of the testing of RR engines where this very feature is demonstrated as a test that the engine has to pass before certification.

N1 only....

[lomapaseo]

Failsafe is extremely difficult to imagine without numbers relating to probabilities. Tis true that some parts of a machine such as wing spars are designed with lots of margin to long life with inspections and consideration of storm encounters, damage etc. But most parts can't meet this same requirement and still maintain the total aircraft weight low enough to get off the ground.

Instead mitigation against the consequences of their failing is considered in a probalistic hazard environment.

Things like redundancy/duplication, shielding etc. are considered at the aircraft system level.

If you want to get into this kind of discussion you have to be prepared to work with probabilities and even with that you are still left with some chance of what happened in this event.

We are waiting for the investigation to reveal the causal chain so that one or two of the links can be altered to minimize a future event. Don't for minute believe you can achieve zero engine disk failures, but you can minimize some specific identified cause based on new knowledge.

The message is always the reaction to what we learn and not blame.

[pax2908]

For instance re. inspections mandated by this AD - who keeps track of the outcome of such inspections? Boeing and GE only? Assuming there is a trend (with enough statistics), are the reliability models revisited?

[barit1]

flyingchanges and funfly:

I recall video footage of the testing of RR engines where this very feature is demonstrated as a test that the engine has to pass before certification....
N1 only....

True it was N1, but the salient fact is that it's a BLADE (airfoil) deliberately released from the fan disk in the referenced video. All new engine models are required to endure this test; The containment for the relatively lightweight blade is established technology. But a DISC failure is several orders of magnitude worse, and containment quite impractical in a flying machine.

[lomapaseo]

For instance re. inspections mandated by this AD - who keeps track of the outcome of such inspections? Boeing and GE only? Assuming there is a trend (with enough statistics), are the reliability models revisited?

Inspection results are reported to the FAA and various models updated as needed. The FAA may update their AD based on any new findings.

At this point I have not seen any linkage between this event and an existing AD but I'm sure they are certainly looking at it quite closely.

[Ka-2b Pilot]

This type of failure is extremely rare but the investigators not only need to find the chain of events which likely caused it but also the following chain of events which caused a lot of fuel to leak out from somewhere, probably onto the ground where it then started to vaporise and subsequently ignited.
With all the videos and other evidence they collect from various sources it may be possible to determine where the fuel exited the aircraft and where the first ignition took place. All this is amongst the myriads of things they will have to look at before trying to determine what steps may need to be taken to minimise the chances of it happening again. These processes could take days, weeks or months, or longer. Then of course there will have to be cost and safety evaluations by various parties….
It has already been mentioned by some that the seat of the fire appeared to be below and not in the aircraft and one of my thoughts is that hot brakes could have ignited it or it could have been ignited by another fire already burning in or around the engine. It may of course be difficult to tell after all the damage caused by the fire(s).

[dsc810]

Many years ago I was told of an industrial turbine that had a disc failure probably operating in some third world country.
I was told the majority of the disc exited though the casing, out though the unit sound proofing canopy, across the site, though a fence, across a road, then it entered a house though the window 'climbed up' a rear wall, so now going vertically upwards, went through the ceilings, 1st floor and roof structure .......whereupon it finally ran out of energy

[draglift]

When you reject a takeoff and bring the aircraft to a halt the pilots are unable to see anything inboard of the wingtips without opening windows. They may or may not have received a left engine fire warning indication, it depends on whether the fire loop for that engine detected heat. If there was a rapidly expanding puddle of jet fuel on the tarmac that was burning and the flames were going on to the fuselage there would not be a fire indication.


I am sure the controllers were extremely busy coordinating fire services and go-arounds.However if the tower had a clear view of the aircraft would it not have been useful if the controller had told the aircraft that there was smoke and flames billowing from the left engine? Armed with that information the evacuation might have been initiated earlier.


I know that if I were to reject a takeoff, having informed ATC I was stopping I would be very grateful for any immediate feedback from ATC as to whether they could see any smoke, flames, inferno etc. Fortunately in the absence of any ATC info there was an extra flight crew member on hand to go back and see what the passengers and cabin crew could see.


If a passenger had panicked and opened door 2 left off their own bat there might have been a very different outcome. As it was what a great outcome and hats off to all concerned.

[Airbubba]

For the avoidance of doubt, that operator currently shows the following memory items for a (non ECL) large Boeing:

1) Aborted Eng Start/Eng Autostart (same single item drill)
2) Cabin Altitude
3) Eng Lim/Surge/Stall
4) Multiple Eng Fail/Stall
5) Fire Eng/Sev Damage/Sep
6) IAS Disagree

Thanks for sharing this.

Only the even numbers have memory items on the large Boeing where I work.

This can't be possible right? Surely I have that sim in the basement and am making this up.

I got the 13 items from Whip's earlier comment:

13 Checklists have memory items. Most of these have 1 or 2 lines
eg ABORTED ENGINE START
Fuel Control Switch ... Cutoff

I heartily congratulate Whip on his retirement and I think our latest reduction in memory items has been since his retirement.

Some of these lists would be called profiles and maneuvers for us, we are indeed expected to know them cold.

However, things that would at one time be considered just common sense troubleshooting, like cycling a transponder, have gradually found their way into a formal non-normal checklist in the AOM (and sometimes, but not always, also in the QRH). And now, Lord help you if you don't write it in the book (or type it on the screen), send a maintenance code and maybe file an ASAP report for CYA whenever anything happens.

Remember when airline manuals only came out every year or two with a few bulletins in between to save printing costs?

Now, with pubs on tablets, revisions seem to be slipstreamed into the manuals almost constantly. At least now you don't have to look at the changes to put the new pages in, right?

Apologies for talking shop so much on a professional pilots forum but these days with events like the BA LAS RTO how you did it is as important to the feds as what you did and how it turned out.

I hope I never see a high speed RTO in the plane (but I'm sure it will be on next year's sim training ) however if I do, hope my coworkers watch me and make sure that we all do it right.

[DevX]

Ka-2b pilot, kerosene's vapour is not flammable like petrol's is.

dsc810, many years ago we had a reheated Spey let go of it's HP disc and it exited at 7-0-clock, chopped through the test cell's main fuel inlet pipe, hit the floor, ran up the test cell wall like a Catherine wheel, along the ceiling, down the opposite wall and buried itself into the substantial steel test cradle. The resulting fire was spectacular and the cell out of commission for weeks. And that's with a small engine. A modern large bypass engine's disc failure is a sight to behold!

[mcloaked]

DevX there is a good set of pictures of an HPT disc failure outcome at:

http://www.dauntless-soft.com/produc...bies/aaengine/.

Or a similar set of pictures is at http://criticaluncertainties.com/201...3-rotor-burst/

[DevX]

Great pics, thanks.

[Ka-2b Pilot]

Porterhouse - see post 248, took a while to find it in all the c**p about baggage.

At DevX, Kerosene most definitely does vaporise and ignite, just at a much higher temperature (about 110 deg F) than petrol (-40F). If it didn't it wouldn't be used for fuel.

[No Fly Zone]

Keeping a Door Closed!

Quote: "If a passenger had panicked and opened door 2 left off their own bat there might have been a very different outcome."

I agree with you, but... Let's keep in mind that the cabin crew are well trained here! On such an aircraft, ALL regular doors are monitored/guarded by a crew member. Regardless of evacuation orders, they are trained to look out the window to assess any potential threat and Before popping their assigned door. If fire/smoke or other problems are noted, their job becomes one of keeping that door closed and directing SLC to another route.
The pix of this event suggest that opening L2 likely would have caused far more serious problems. That much I'm sure about.
What I do not know is how cabin crew monitors the Over-Wing exits in a similar event. In this case, popping the first Left Over-Wing hatch would have been almost as bad as opening L2. They do not have sufficient staff to monitor the Over-Wing pop (in or out) hatches and I do not know how they control their use. Does anyone out there know?
I think it is already obvious that this event demonstrates both extremely professional action by the BA crews, ATC, Fire Staff and others, as well as a significant measure of ordinary luck. Had the flight crew not noticed 'a problem' for an additional 20 seconds, this event would probably not be enjoying a happy ending.
The single item that continues to trouble me is the firm evidence the the IDIOT Passengers continue to haul their carry-on bags out with themselves. It is a stupid practice, very common and yes, I kow that I'm preaching to the choir.