AirAsia Jet Plunges 24,000 Feet in Just 9 Minutes

deonb

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deonb
And by "plunges" they mean: "Descend at 2600 fpm".

https://www.nbcnews.com/storyline/a...et-plunges-24-000-feet-just-9-minutes-n810971

Of course the FA's are to blame for the panic, but curious what is the procedure from the cockpit for doing a rapid descent?

Shouldn't the pilot or FO come on over the PA and announce: "Hey folks, we're just flying down to a lower altitude to get you some breathable air - we'll get there in 10 minutes and then you can take the masks off". Or something like that.

I'm a bit surprised the pilot didn't at least inform the FA's of what was going on.

You got to laugh at the "lots of people pulling out the life jackets" comment though. Mmm, ok:

upload_2017-10-16_14-54-30.png
 
During a rapid descent, the pilots put on their oxygen masks. Passengers probably wouldn't understand what they were saying anyway. They are a bit busy during this emergency procedure. Getting to 10K all that matters.
 
Aviate, Navigate, and THEN Communicate. Talking to the passengers DURING the emergency descent is the absolute last thing on the pilots' minds in that case.

Sounds like the Flight attendants need more or better training.
 
As a passenger I’ve seen many safety briefings about putting on an oxygen mask. The video versions of these briefings seem calm, with no hint that the plane is not level, but is in fact descending fast.

I wonder why they don’t mention that this O2-mask-donning would be done during a rapid descent and that is nothing to be alarmed about.
 
I've been up front in an A320 a couple times and 2,000'/min was pretty common during the descent.

This does bring up a question - why did the pilot only descend at 2600 fpm? Wouldn't you want to get to 10'000 ft in like 5 minutes to prevent hypoxia?
 
I believe Pax oxygen masks are actually some reaction that happens to generate oxygen and only lasts 10 minutes or so. As long as they get to 10k once those run out everyone is ok.
 
Nice to know ,that the people giving the safety briefing,are ready to perform in a professional manner.
 
And by "plunges" they mean: "Descend at 2600 fpm".

https://www.nbcnews.com/storyline/a...et-plunges-24-000-feet-just-9-minutes-n810971

Of course the FA's are to blame for the panic, but curious what is the procedure from the cockpit for doing a rapid descent?

Shouldn't the pilot or FO come on over the PA and announce: "Hey folks, we're just flying down to a lower altitude to get you some breathable air - we'll get there in 10 minutes and then you can take the masks off". Or something like that.

I'm a bit surprised the pilot didn't at least inform the FA's of what was going on.

You got to laugh at the "lots of people pulling out the life jackets" comment though. Mmm, ok:

View attachment 57161

mscard nailed it. Priority is to dump lift by banking, reduce power to idle, and descend as rapidly as possible. In the pax briefings I have received on airlines the phrasing has been "In the event of a change in cabin pressure,,,,," followed by the oxygen generator instructions. I agree that the cabin crew needs more training.

Bob Gardner
 
mscard nailed it.

Bob Gardner

Thanks Bob, but it was something we flew in the sim usually every job check, I mean, check ride. It was actually fun.

And yes, that cabin crew, wow.
 
This does bring up a question - why did the pilot only descend at 2600 fpm? Wouldn't you want to get to 10'000 ft in like 5 minutes to prevent hypoxia?
Can't do it. You can only dirty it up with brakes and descend at barber pole. 2600 Fpm sounds about maximum for the Bus. Perhaps a bit light, but in the ballpark.

In addition, once the masks are on it's pretty much a non issue.
 
This does bring up a question - why did the pilot only descend at 2600 fpm? Wouldn't you want to get to 10'000 ft in like 5 minutes to prevent hypoxia?
I think the certification requirement is below 25,000 feet inside two minutes. Anything from there on down won't damage most passengers who aren't quick enough to get a mask on.
 
As a passenger I’ve seen many safety briefings about putting on an oxygen mask. The video versions of these briefings seem calm, with no hint that the plane is not level, but is in fact descending fast.

I wonder why they don’t mention that this O2-mask-donning would be done during a rapid descent and that is nothing to be alarmed about.

Nothing to be alarmed about? :fingerwag:

Remember, they have just been told the masks drop due to a loss of cabin pressure. :eek:
 
Can't do it. You can only dirty it up with brakes and descend at barber pole. 2600 Fpm sounds about maximum for the Bus. Perhaps a bit light, but in the ballpark.

In addition, once the masks are on it's pretty much a non issue.

Hmmm. AF 447 managed 10,000 ft/min with the nose up and throttles firewalled. :(
 
Sounds like the stews could use a little work on their bedside manner if what the passengers said is true
 
Just slip it.
Wasn't there a guy in a B7something or other that ran out of gas in Canada, dead sticked it and found a drag strip. Was a bit high and slipped it in. When I read about it it was a big deal that he did that. Like that he even thought of it was unusual. What's the story on 'the big iron,' can you do a foot to the floor slip in one of those things?
 
Wasn't there a guy in a B7something or other that ran out of gas in Canada, dead sticked it and found a drag strip. Was a bit high and slipped it in. When I read about it it was a big deal that he did that. Like that he even thought of it was unusual. What's the story on 'the big iron,' can you do a foot to the floor slip in one of those things?
The Gimli Glider. Slipping with pax is just a bit unusual...(and I think a bus just says “sorry Dave”)
 
I'm sure the folk way up front and way in back got quite ride
I’ve been in the back of a 737 doing skidded turns on an approach. It wasn’t much fun. It was one of those flights where ya expect to see a tea kettle fired up so the skids were just an added feature.
 
Wasn't there a guy in a B7something or other that ran out of gas in Canada, dead sticked it and found a drag strip. Was a bit high and slipped it in. When I read about it it was a big deal that he did that. Like that he even thought of it was unusual. What's the story on 'the big iron,' can you do a foot to the floor slip in one of those things?

B767. Put it down on a former Air Force base at Gimli, Manitoba that was converted to a motorsports park after being closed. Left seater was an experienced glider pilot. Right seater was a former Canadian Air Force pilot who had once been stationed at Gimli. But neither they nor ATC knew the place was hosting car races, so a pretty exciting short final for them and those on the ground. They had to slip it in because zero hydraulics meant no slats/flaps.
 
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B767. Put it down on a former Air Force base at Gimli, Manitoba that was converted to a motorsports park after being closed. Left seater was an experienced glider pilot. Right seater was a former Canadian Air Force pilot who had once been stationed at Gimli. But neither they nor ATC knew the place was hosting car races, so a pretty exciting short final for them and those on the ground. They had to slip it in because zero hydraulics meant no slats/flaps.
I googled Gimli Glider. That was definetly the incident I remembered. Kinda cool they got that Outstanding Airmanship Award even after getting suspended for running out of gas. Between this guy, who was an experienced Glider Pilot, and Sully you have to put some stock in Glider experience. Except for the fuel management part, lol.
 
Kinda cool they got that Outstanding Airmanship Award even after getting suspended for running out of gas

A suspension which was successfully appealed.
While there were certainly opportunities for the crew to prevent the Gimli Glider event, they were hampered somewhat by maintenance crew actions, and the lack of a Flight Engineer, and the challenge of newly required metric conversions.
 
I googled Gimli Glider. That was definetly the incident I remembered. Kinda cool they got that Outstanding Airmanship Award even after getting suspended for running out of gas. Between this guy, who was an experienced Glider Pilot, and Sully you have to put some stock in Glider experience. Except for the fuel management part, lol.

Hard to argue that one.

Canadians seem to have a particular interest in seeing how far they can glide passenger airliners with dead engines. :D

The Gimli Glider distance record was broken by another experienced glider pilot, Robert Piche, in an Air Transat A-330. Flamed out over the Atlantic, and he and his FO, Dirk de Jäger, dead-stacked it to a landing in the Azores. I think they still hold the all-time airliner glider distance record.
Air Transat Flt 236 if you decide to look it up.
 
UAL did better than 3000 feet per minute descent today in their 737. ForeFlight was had a warning about a fast descent a few seconds before I captured the screen.
 

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UAL did better than 3000 feet per minute descent today in their 737. ForeFlight was had a warning about a fast descent a few seconds before I captured the screen.
A rate of descent will get faster as altitude decreases. The barber pole will climb and we can put the nose down more as altitude decreases, thus increasing rate.
I wouldn't be surprised at double that once you hit the 20's.
 
A rate of descent will get faster as altitude decreases. The barber pole will climb and we can put the nose down more as altitude decreases, thus increasing rate.
I wouldn't be surprised at double that once you hit the 20's.
I think FinnAir got to 5000'/min when I flew them a few weeks back but I'd have to parse the track to be sure. Seems to support what you said.
 
I think FinnAir got to 5000'/min when I flew them a few weeks back but I'd have to parse the track to be sure. Seems to support what you said.
One other thing to consider is the reason for the rapid decompression?? If structural failure it is suspected it may be wise not to descend close to barber pole (red line).
Again, once the crew has their masks on everything else should be considered as a non rushed situation.
 
I've done a space shuttle decent trying to get into a alternate that was straight below us.

20° flaps, speed brakes, idle thrust, and speed mode at 250 knots will get you one hell of a decent in a CRJ.

We typically will do 2000/2500 fpm trying to help Charlotte approach out. While Republic is bumping along with their autothrottles doing a 25 mile final I can get us down from 8000' in the downwind to a under 10 mile final.

Idle decent in a CRJ is about 3.2-3.6°. Which is about 2000-2600 fpm.
 
I've done a space shuttle decent trying to get into a alternate that was straight below us.

20° flaps, speed brakes, idle thrust, and speed mode at 250 knots will get you one hell of a decent in a CRJ.

We typically will do 2000/2500 fpm trying to help Charlotte approach out. While Republic is bumping along with their autothrottles doing a 25 mile final I can get us down from 8000' in the downwind to a under 10 mile final.
What will that give you for fpm? At 250 in the Bus your scenario will be no more than 2500.
At 210 you're lucky to get 2000.
 
What will that give you for fpm? At 250 in the Bus your scenario will be no more than 2500.
At 210 you're lucky to get 2000.

If I throw the 20° flaps out and keep it in speed mode at 210 I'm thinking I can get it somewhat above 2000. I've actually never paid much attention to it during the approach. I'll try to remember to look during my next trip.

It's common enough that Charlotte will just tell us to "make it quick". Especially behind Envoy or Republic! LOL
 
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