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PT6A
21st Apr 2012, 10:16
With the recent event at LGW with the Virgin 330 it got me looking into the books and thinking about the procedure.

At what point would you come to the decision to order an evacuation.

Here is my train of thought.

Inflight smoke warning, complete ECAM leading to LAND ASAP.

Head to a suitable airport for landing (brief the cabin crew for the return, that after landing they should expect "attention crew on station" and to be in their positions but not to open any doors without further commands from the FD.

Allow the fire service to inspect the hold (with the hold door closed) using thermal image equipment.

If the result was no sign of anything untoward then disembark the passengers via steps.

If the fire service reported heat or there was signs of smoke on the aircraft or outside - then I would order an evacuation.

I think my thoughts are inline with Airbus procedures (as they use the word evacuate and disembark in their FCOM, ECAM and QRH so obviously differentiating between the two)

Anyone do it differently?

I can see the potential in these circumstances for a cabin initiated evacuation either by crew or passengers. As opposed to awaiting instructions from the FD.

* I'm not asking specifically about the VS flight as at this stage we don't know what the crew were presented with in terms of exact information from the fire service and or any signs of smoke.

Yaw String
21st Apr 2012, 10:24
Expect as many opinions as there are airlines, on this one.
Just don't expect to be allowed anywhere near the terminal after landing, even if is a suspected false indication...
Given that you decide on a precautionary emergency disembarkation remember,..the stairs they present you with may not be 100% adequate for your aircraft..and the clock is still ticking..

PT6A
21st Apr 2012, 10:30
I would also add into my post... My decision could well depend on the airport we had landed at and my faith in their fire and rescue service..... I'm not sure if at all airports around the world they may even be equipped with thermal image equipment?

But landing back into the UK I would feel comfortable to act upon the advise of the fire service.

TolTol
21st Apr 2012, 10:48
If the fire warning is still active after fire drill has been accomplished we're taught in the simulator to evacuate. Remember the China Airlines 737 bursting into flames? Not much time there to wait around for fire services to inspect the aircraft and offer advice.

PT6A
21st Apr 2012, 10:50
Toltol it's is not a fire warning.. And the light won't extinguish because you have filled the compartment with extinguishing agent... And there is no way for that agent to escape. Airbus specifically tell you the light will remain illuminated.

LAND ASAP

CABFANS..................................................... .........................................OFF
IF FWD (AFT) CRG CLOSED (displayed on ground only): Order the ground crew not to open the door of the affected cargo compartment, unless the passengers have disembarked and fire services are present. Also ensure that the FWD(AFT) cargo door is closed before discharging the extinguishing agent.
AGENT....................................................... .......................................DISCH

Note: Expect the SMOKE warning to remain after agent discharge, even if the smoke source is extinguished. Gases from the smoke source are not evacuated, and smoke detectors are also sensitive to the extinguishing agent.

ON GROUND BEFORE OPEN CRG DOORS: PAX......................................................... ........................DISEMBARK
BEFORE OPEN CRG DOORS (displayed on ground only): PAX........................................................D ISEMBARK

BUGS/BEARINGS/BOXES
21st Apr 2012, 11:17
There is no separate CRG FIRE warning, only SMOKE. Therefore one has no idea if there is infact a fire burning, or if the first bottle (60 sec discharge)did it's job. Some smoke in the cabin might be a sign, but depends we're the burning article was in relation to the ventilation system/smoke detector location. If a burning object was right by the detector, then the vent would probably be shut before smoke even reached it. If my arse was on fire, I'd throw them down the slides rather then face a possible British Airtours scenario.
It would be interesting to see what the article was. Let's hope something one-off -ish, because if it's one of these lithium ion batteries......

PT6A
21st Apr 2012, 11:31
The last information I got was the fire service did not find any trace of fire in the hold? Anyone have any other info on that?

PT6A
21st Apr 2012, 11:59
I like tea.. I was thinking about that myself.... It is a tough one!

My take on the Airbus advise is they are really leading you towards not evacuating... Unless you get information from a source other than the aircraft systems (actual smoke, fire or fire service reports)

Of course they can't say don't evacuate.. Because there are so many variables, but it does leave us in an area where people have various opinions.

I would imagine if the fire service are watching the hold with their thermal imaging camera and can't detect anything untoward and they continue to watch it (which they would) the risk would be pretty low (probably lower than the risk due to an evacuation)

In the event something did go Amis you can start an evac and they are already in a position to put several 1000 GPM of foam onto the "fire" actually within the space of a couple of seconds could completely fill the cargo hold with foam.

PT6A
21st Apr 2012, 12:18
I'm sure I read it was a cargo smoke warning on the VS flight (however I won't stake my pension on it) nevertheless I think thisis a worthy discussion to have, albeit in a more general sense.

TolTol
21st Apr 2012, 16:40
Ah sorry I'm coming from a Boeing. Would have thought they would have similar procedures. We have smoke detectors in the cargo compartment, but they generate a fire warning, not a smoke warning (where there's smoke there's fire Im guessing is their thinking). And as far as I know the light extinguishes if smoke is no longer detected.

Hence, if the light stays illuminated then we evacuate. However, what if the light does extinguish? Our QRH does say not to open the cargo doors until all passengers and crew are off the aircraft. Am I going to taxi to a remote stand and wait for steps? I suppose if there's is no other indications that there is a fire then yes.

Halfbaked_Boy
21st Apr 2012, 17:53
I personally wouldn't delay - if no visible signs of smoke, we stop on the runway and disembark. If there's any sign whatsoever that there is an active fire, evacuate immediately. PT6A, to relate to one of your points, I just cannot depend on the reliability of the fire teams efficiency (not in any way meaning to offend here, it's just a personal feeling).

I would head back and supervise the disembarkation, and upgrade to 'mayday' if it necessitated.

scoobydoo44
23rd Apr 2012, 10:11
afs do have 2 thermal image camera on the run. initial inspection is done externally using drive round by oic, in stand alone vehicle who will be in comms with crew on discreet channel. The stairs that have been mentioned in previous posts are primarily so that the afs can use them to gain entry with hose and other equip , instead of using ladders which would be more hazarsdous, however they do have a multi purpose use for evac pax also ,

Wizofoz
23rd Apr 2012, 10:54
Hence, if the light stays illuminated then we evacuate. However, what if the light does extinguish? Our QRH does say not to open the cargo doors until all passengers and crew are off the aircraft. Am I going to taxi to a remote stand and wait for steps? I suppose if there's is no other indications that there is a fire then yes.

Tot,

The Boeing QRH makes the note about not opening the Cargo Door in reponse to the Cargo Fire detection being ON, not Off after the condition no longer exists.

I've never seen a Boeing Checklist which mandates an evacuation in response to a cargo, or indeed ANY fire indication. Your airline may teach it, but it is neither a Boeing, nor universal procedure at all airlines.

With a Cargo Fire warning with no other indications of fire it may well be worth considering a precautionary disembarkation rather than a full on EVAC- you are less likely to hurt people.

PT6A
23rd Apr 2012, 11:05
Wizz...

There does seem to be a slight difference in the Bowing v Airbus.. In that Oeing seem to say the light will go out.

Airbus on the other hand virtually rule that out. (due to the hold being unable to evacuate the extinguishing agent)

Is there a way for the extinguishing agent to be evacuated from the hold on a Boeing? I would of thought the detection equipment is pretty similar between the two makes.

Wizofoz
23rd Apr 2012, 11:50
PT,

Just going on what I'm current on (777), the NNC doesn't really cover it going out or staying on-once the fire is detected, the NNC should be completed.-As to the extinguishent clearing,quite the opposite. The compartment ventilation is by-passed, and the bottles are sequenced to keep extinguisent in the hold, so it's unlikely the condition would clear even with the fire off.

That being said, the Aeroplane is 330m ETOPS based on the idea it can contain a cargo fire for that long, so, absent any secondary indications of an imminent cabin infiltration by smoke or flames, taking a minute to assess and maybe do a Precautionary Disembarkation would seem sensible.

Golf-Sierra
23rd Apr 2012, 12:18
The advent of digital systems has clearly had some kind of feedback effect on humanity and we are seeking binary solutions to all problems. Surely between the 90 second certification requirement for pax evacuation and the 15 or so minutes required for disembarkation via stairs on the runway there is some middle ground?

Passengers can be evacuated in an orderly fashion, without being shoved off, and given enough time to leave the bottom of the slide so pileups do not form. Should further evidence of an actual fire present itself the evacuation can be briskly expedited to run-for-your-life speed. Should CC not apply this kind of common sense when dealing with a situation like this? I am not criticising the CC personally, as I expect they are obliged to follow typical dumbed down SOPs.

Golf-Sierra

PT6A
23rd Apr 2012, 12:25
Wizz,

Sounds the same as the bus.. First we cut of the ventilation and then discharge the agent into the hold.

It just surprised me that some posters seem to hold the opinion that light on = smoke and light off = no smoke.

I'm surprised we don't get more spurious warning TBH, the amount of times I have had to be evacuated from a hotel because someone was putting on their Lynx in the vicinity of an optical smoke detector.......

This is where the use of all available resources comes in.. Keeping a eye on the hold temperature does help to confirm / disprove the warning.

I'm curious what halon wold look like when discharged into the hold? Many people advocate the use of a camera in the hold.. But having never seen halon discharged in a confined sealed space.. I'm not sure if that would look like smoke on CCTV?

GS.. I agree with your comments. I will be very interested when the VS report is issued who initiated the evacuation, at this stage we don't know if it was a cabin initiated evacuation by either cabin crew or passengers.

Trouble is.. If the passengers had got wind about a possible fire in the hold, I'm sure they would of been very difficult to control.

Having said that the reports of the cabin crew "screaming like a banshee" seem to indicate they were ordered or defaulted to a full evacuation.

TolTol
23rd Apr 2012, 12:45
Wiz,

Our 737 QRH doesn't distinguish between light on or off with regard to the warning about opening the cargo door. In fact, it makes no reference to the light going off.

Must be a company thing with regard to evacuating with a fire warning.

PT6A
23rd Apr 2012, 13:00
The door should never be opened with anyone onboard the aircraft after an activation of the smoke warning.

If there ever was a fire... The halon may well of done its job, but halon does not have the ability to cool the embers... So as soon as the door is opened and a fresh source of oxygen is introduced you could have a very nasty surprise.

Much better for the door to be opened once everyone is off and you have a couple of firefighters at the ready with a jet!

Another reason to be carefull opening the doors...... the urban legends of various animals getting loose in the hold:E

Gulf News
23rd Apr 2012, 13:06
I've never seen a Boeing Checklist which mandates an evacuation in response to a cargo, or indeed ANY fire indication. Your airline may teach it, but it is neither a Boeing, nor universal procedure at all airlines.Wiz the following comes from your own companies B777 QRH checklist instructions/ non normal checklists.

It must be stressed that for smoke that continues or a fire that cannot be positively
confirmed to be completely extinguished, the earliest possible descent, landing,
and evacuation must be done.

PT6A
23rd Apr 2012, 13:23
The incident aircraft was an Airbus..

However, they would of had available to themat least two other sources of information regarding the status of the hold once on the ground.

The cargo temperature indication and reports from Fire Service over the radio who would be scanning the hold with their thermal imaging equipment.

This is why Airbus feel confident enough to say that you may disembark the passengers not evacuate them.

A decision to evacuate must not be taken lightly as you will cause injury to passengers.

With the fire service report that the hold is not showing signs of heat, the indication that everything is normal on the cargo temperature indication.. Coupled with firefighters standing by outside the aircraft with the capability to fill the hold with agent within a few seconds.....

Can you really justify causing injury to passengers as opposed to a controlled disembarkation by steps? Keeping open the option to evacuate if the nature of the incident changes.

If the fire service reports that the hold is showing signs of heat or smoke issuing then it is a completely different situation.

Wizofoz
23rd Apr 2012, 14:23
Wiz the following comes from your own companies B777 QRH checklist instructions/ non normal checklists.

It must be stressed that for smoke that continues or a fire that cannot be positively
confirmed to be completely extinguished, the earliest possible descent, landing,
and evacuation must be done.


Indeed it does, and forms part of Boeings recomendations regarding handling such incidents repeated in the FCTM.

Please understand that by "Fire Indication" I meant cockpit annunciation. Obviously a fire confirmed by other indications (smoke, flame, heat) is a completely different thing and would indeed mean an evacuation.

It does not however form part of any individual checklist. Nor does it cover the case where it has not been positivley confirmed that a fire exists in the first place, or that indications are that a fire HAS been extinguished.

Are you suggesting that this paragraph means that any fire warning must necessarily lead to an evacuation, without seeking confirmation or otherwise from other sources?