UA497 Smoke, Emergency Landing and Evacuation

[wiggy]

Shell M

If, as has been claimed by Airbus drivers here, that the checklist contains the caveat:

IF SMOKE EXISTS

Then perhaps we'd better wait until we see the incident/accident report before handing out the s

[BOAC]

One thing is certain - IF the call went out 'we've lost ALL our instruments" and the NTSB report is also correct, someone will, by now, hopefully have educated that particular pilot as to what ALL means and what that sort of call means to a controller.

[misd-agin]

Airbus. Random E&E smoke warning for a couple of days. MX couldn't find the problem. Ops check normal....

Happens to us at TOC. Intermittent, then full warning w/ECAM. No smell through the sniffer tube.

We divert. Give FO the a/c. Idle/speedbrakes until configured since the divert field was pretty close.

Mx found faint smoke smell in E&E. Mechanic and I climb around E&E trying to find source. Insulation touching runway turn off lights. Use of turnoff lights, and length of use, apparently the reason behind the random nature for several days.

That fact that they couldn't smell anything is no different than it was in my case. We had no smell but a possible source of ignition.

[aterpster]

BOAC:

One thing is certain - IF the call went out 'we've lost ALL our instruments" and the NTSB report is also correct, someone will, by now, hopefully have educated that particular pilot as to what ALL means and what that sort of call means to a controller.

I doubt that crew will be flying in the near future.

[FIRESYSOK]

They had already declared mayday. At that point the crew get anything they desire, including a surveillance approach which was specifically asked for by the captain. Listen to the tapes. He could have asked for a PAR regardless of his instrumentation, weather, etc. and it would have been delivered, no questions asked.

Maybe the Brits think something of this (obvioulsy) but obviously, it was not at issue here. What is at issue is what triggered the faults, was there smoke, and was the crew guilty of gross negligence for landing because of a smoke warning. My guess? The crew is already back flying and the nexus of the investigation is the aircraft in question. That's the way it works here and with any luck will continue to do so.

[lomapaseo]

Sadly in the US there is an increasing tendancy to rapidly blame the crew for everything to try to avoid NTSB opening up training sytem and management issues.

A collective "US" vs the "world" comment like this is not appropriate to a valid argument. Contrary to what is often portrayed on discussion boards, investigators, advisory or government, are not involved in the blame game. The contributing factors are all considered and if the crew is in the chain either from omission, or causal then it's expected that the final recommendations will address the reasons for their involvement.

The most simple blame has a tendency to go to the lowest common denominator either mechanical or symptom "were it not for"........
However the presumption of an average skill crew response need also be weighed as an investigative finding in the final recommendations by the board in charge.

[MountainBear]

The report did say this incident started with an A/T message or disconnect which by itself is not a big deal but followed by an ARINC smoke or avionics smoke message, this situation warranted a return in my opinion. Had this been a real avionics bay fire, it wouldn't have seemed prudent after the fact to have waited for my nostrils or eyes to detect particulates.

Exactly. Why have a mechanical instrument to detect what one's biological instruments (nose and eyes) cannot if, when push comes to shove, you are only going to rely on the biological instrument. It makes no sense whatsoever.

Seriously, if you are not going to believe your instruments, why have them.

[BOAC]

I haven't followed this thread in detail, but is there some criticism somewhere on it of the decision to declare a Mayday and RTB?

[Zeffy]

but is there some criticism somewhere on it of the decision to declare a Mayday and RTB?

Although some posters may be interpreting the comments in that fashion, the "criticism" (discussion, I thought) shouldn't be focused on the decision to return and land, but rather on how the event progressed from the initial warning of avionics smoke to a deployment of the RAT -- i.e., --

Was the appropriate checklist followed precisely by the crew?

Was the checklist itself properly constructed?

Were other electrical/mechanical faults not apparent to the pilots?

[Jetjock330]

Being only A330/340 rated, I can say that going into Emergency Electrical config is a RED land ASAP, with with planning in mind. Adding any form of smoke into this equation highlights the point of landing even sooner.

A pilot is able to restore from Emergency Electrical configuration, but will not be able fully restore and there some consequences, hence the request for the longest runway. The RAT is driving the green hydraulic system, which is driving the Emergency Generator, therefore the landing gear needs to be dropped via the Emergency gear down, so as not to interrupt to RAT driving the EMER generator circuit, leaving no nose wheel steering amongst other things after landing. (I am not A320 qualified and no time in it)

Smoke in the Airbus checklist is bit like having the evening fireplace smoking into the living room. Doing a SMOKE REMOVAL by opening the windows ain't going to stop the smoke. First the scource needs to be isolated via, aircon packs off, or isolating electrical busses, the electrical supply. This in turn would supposedly stop the living room fire and now the SMOKE REMOVAL is applied.

If in doubt and SMOKE still persists, turn the power off to the house (put the aircraft ino EMER ELEC CONFIG) and consider opening the windows if needed, but the point is, the problem/scource needs to be found first first.

Some folk feel the need to go straight to main box and kill the power to the house (put the aircraft ino EMER ELEC CONFIG) and then deal with the source, which is not always the way to deal with it.

AVIONICS SMOKE is detected in the outflow(exhaust flow), so it is more difficult to tell which radio/computer is being fried, but it may not put smoke into the cockpit, as it is only being detected in the avionics exhaust flow. Different checklist, although important too.

[Ditchdigger]

AVIONICS SMOKE is detected in the outflow(exhaust flow), so it is more difficult to tell which radio/computer is being fried, but it may not put smoke into the cockpit, as it is only being detected in the avionics exhaust flow.

I hope this isn't a stupid question, and I realize that it may be unaswerable in any specific sense--how long might one expect between the initial smoke message, and the point at which shutting off the electrical supply wouldn't help? In other words, how much time does a crew have to consider the possibilities and react before a fire would become self sustaining?

Makes one wonder if all non-aircraft runway operations should include a bulldozer among the equipment - to ensure the runway can be cleared on three minutes notice.

I know this aspect of the incident hasn't had much discussion, but if anyone is interested, I can comment about the performance of a milling machine such as the one involved here. Among those of us who play in the dirt rather than the sky, the consensus of opinion is that to try and take it directly into the grass would probably have resulted in it getting stuck before it was far enough off for the runway to be considered "clear". (Unlike much construction equipment, they're not intended to be run off-pavement.) Also, with a top speed in the neighborhood of 10 mph, 3 minutes wouldn't be a unreasonable expectation to reach the nearest taxiway.

[Airbus_a321]

maybe they were a little bit too fast with the procedure and therefore rushed into the procedure and created the "homemade" mess.

According the press release:

the preliminary examination has not revealed any signs of burning, indications of smoke or other anomalous system findings.

neither crew member recalled smelling smoke or fumes during the flight.

The QRH says clearly:

AVNCS SMOKE - if perceptible smoke apply.....do this and this and that etc...

further down in the procedure:

QRH "...at any time of the procedure if smoke becomes the greatest threat
ELEC EMER CONFIG.....CONSIDER

QRH "...Refer to the end of the procedure to set ELEC EMER CONFIG..."

Now I guess they rushed into and applied this procedure, although there was no smoke.


@firesysok

it's possible they did de-power the airplane as directed but the RAT deployed for reasons unknown

... the RAT deployed IMHO not for reasons unknown, but for reasons VERY WELL KNOWN.... because

to set ELEC EMER CONFIG you must switch:

- EMER ELEC GEN 1.....OFF
- EMER ELEC PWR ..... MAN ON (...and now the RAT is already in the air.....)
now the QRH says
WHEN EMER GEN AVAIL:
- APU GEN....OFF
- GEN 2.......OFF

et voila, ...now you have to deal with the "$hit" that you are in

ELEC EMER CONFIG ....and this is not a nice situation. not at all.

I agree with Nigel #39

and I think they did not ....a great job as well....(@DingerX)

wait and see

[Che Guevara]

UAL does not use use the 'standard' Airbus Checklists, indeed their Avionics Smoke procedure is very straight forward by comparison and covers all the important aspects of the situation.

However, similar to the Airbus checklist there is a line, 'IF PERCEPTABLE SMOKE', which I suspect might be interpreted by some as a positive, if they have an Avionics Smoke ECAM warning. I am not suggesting this happened in this case, as I too look forward to the report when it comes out.

The UAL checklist later mentions: IF SMOKE AFTER 5 MN:
EMER ELEC GEN 1 LINE ......OFF, which leads into the EMER ELEC CONFIG. etc.
Again, could this be interpreted as a positive if the Avionics Smoke ECAM Warning still exists?

My point is that Smoke and Fire are unquestionably one of our greatest threats and their should be little or no doubt how to proceed if faced with this problem, whether it is a training issue or checklist design, we need to be very certain what to do and when to do it. There can be no ambiguity.

[MountainBear]

However, similar to the Airbus checklist there is a line, 'IF PERCEPTABLE SMOKE', which I suspect might be interpreted by some as a positive, if they have an Avionics Smoke ECAM warning. I am not suggesting this happened in this case, as I too look forward to the report when it comes out.

That is the rational way of understanding it.

I'm not trying to prejudge the matter, either. In fact, I'm not commenting on their performance at all. But anyone on these forums who suggests their decision to return was wrong solely because they failed to see or smell smoke is bonkers. That nothing more than outcome bias, which is pure error.

[bubbers44]

In a 757 i had smoke fumes in the cabin and cockpit and did an emergency return to the departure airport. It wasn't a big deal but had firetrucks waiting for us. We just did what the procedure said and landed.

[Airbus_a321]

@mountainbear

their decision to return was wrong

.....no bear, guess nobody here will question that the decision to return was wrong....but to switch the aircraft into EMER ELEC CONFIG...obviously without need...see above...was wrong

btw: in my career I had at least 5x AVNCS SMOKE without actual smoke. no findings, except for poor filter quality , which were installed at this time. anyway those filters are very sensitive in creating an ECAM signal.
Maybe Airbus trusts the pilots eyes and noses more than it's installed AVNCS SMOKE sensors and for this reason: if perceptible smoke

[Graybeard]

Did you ever notice how smoke sneaks up on you, and you don't notice it until it is sometimes really bad? Your nose/brain adapts to odors that come on slowly. That's why an electronic smoke sensor is important. It senses absolute density, and does not adapt to increasing levels.

[Cytherea]

Don't rush to criticise...

Before we all jump on the bandwagon take a moment to read this:
Transportation Safety Board of Canada - AVIATION REPORTS - 1998 - A98H0003

How many of the causes and contributing factors the SR111 investigators identified in their final report are/could be the same here in terms of smoke detection etc? The crew cannot be criticised in their turnback decision - they and may learn lessons for the future and apply those in the future for safer flight.

[Zeffy]

NTSB Docket with four pages of materials.

[drive73]

Nothing like hours of time and a well read report, as usual the pilots had much less time and much less info to judge the situation. Other than a structural failure fire is probably the worst situation you can have. Ecam message of fire would defiantly get me thinking about getting power off and getting it on the ground ASAP. Just think what the discussion would be if they had waited until they saw or smelled smoke, disregarding the ecam, crashed and killed everybody.