[Seattle S65B40]

http://www.cnn.com/2011/WORLD/americ...ex.html?hpt=T2

For those of you that fly, you know how important it is to know true airspeed at all material times. It didn't help that the pilot was not in the cockpit and they had kids for co-pilots... Very sad and my heart goes out to the victims families.

[Freakazoid]

Originally Posted by Seattle S65B40

http://www.cnn.com/2011/WORLD/americ...ex.html?hpt=T2

For those of you that fly, you know how important it is to know true airspeed at all material times. It didn't help that the pilot was not in the cockpit and they had kids for co-pilots... Very sad and my heart goes out to the victims families.

I saw this a little bit ago.
Is it me or does the article not read well?

They say "At the time of the descent, the two co-pilots and captain were in the aircraft cockpit."
but then they say "The report said that at this time co-pilot PNF tried several times to call the captain back to the cockpit."

I know it seemed to be broken up into separate events, but seems confusing to me.

RIP to all of them though

[Seattle S65B40]

Originally Posted by Freakazoid

I saw this a little bit ago.
Is it me or does the article make no sense?

They say "At the time of the descent, the two co-pilots and captain were in the aircraft cockpit."
but then they say "The report said that at this time co-pilot PNF tried several times to call the captain back to the cockpit."

Which is it?

He was not in the cockpit. He was resting as part of their routine for long flights. He came in a couple of minutes before the crash. May have been the critical factor. He may have been experienced enough to know to nose down despite conflicting air speed info. Report is that engines remained operational which is somewhat confusing as well.

The horror on the plane as it dropped 38000 feet in just over 3 minutes is unimaginable.

[JoosyJoos]

Ya they screwed up big time. The glide rate on the A330 is fairly decent if they hadn't completely throw the thing of tilt.

[Blake]

What I don't get is why the pilots couldn't identify a pitot malfunction pretty quickly. There are redundancies in place that could have prevented this accident. Flying in a storm at altitude is a known icing condition. I wonder why they didn't even bother to check their speed on either GPS or INS. I dunno...a lot of this sounds similar to the Avianca accident.

[Seattle S65B40]

Originally Posted by Blake

What I don't get is why the pilots couldn't identify a pitot malfunction pretty quickly. There are redundancies in place that could have prevented this accident. Flying in a storm at altitude is a known icing condition. I wonder why they didn't even bother to check their speed on either GPS or INS. I dunno...a lot of this sounds similar to the Avianca accident.

I was wondering about GPS speed as well. The co-pilots were 32 and 37 years old. Not exactly kids, but I doubt they were experienced enough to keep their focus during this event.

[Blake]

Originally Posted by Seattle S65B40

I was wondering about GPS speed as well. The co-pilots were 32 and 37 years old. Not exactly kids, but I doubt they were experienced enough to keep their focus during this event.

I dunno about all that. The pilots were obviously experienced enough to be flying TATL flights on a widebody jet. I don't think it helped that the most experienced pilot was asleep and came in mid-way through all the critical events. That just causes more delay in the troubleshooting by having to catch him up on everything. I think panic played a palpable part of all this as well. Seems as they just started cranking on all the controls.

[jpsum]

Originally Posted by Blake

What I don't get is why the pilots couldn't identify a pitot malfunction pretty quickly. There are redundancies in place that could have prevented this accident. Flying in a storm at altitude is a known icing condition. I wonder why they didn't even bother to check their speed on either GPS or INS. I dunno...a lot of this sounds similar to the Avianca accident.

That's because they were getting different readings from different systems. There's no way you can tell how fast you are flying just by FEEL, so there is really no way to tell which reading is correct. It sounds like they thought the plane was flying too fast, so they pulled the nose up.

As far as redundancy, there're redundant air speed sensors (3 i think), but they suspect that they all iced up and failed. Once you lose track of air speed at 38k feet, you are in pretty deep shit. Flying too slow = stall. Flying too fast, the plane will actually rip apart. And the margin between flying too fast and too slow at 38k feet is relatively small. The higher you fly, this margin becomes smaller.

[Blake]

Originally Posted by jpsum

That's because they were getting different readings from different systems. There's no way you can tell how fast you are flying just by FEEL, so there is really no way to tell which reading is correct. It sounds like they thought the plane was flying too fast, so they pulled the nose up.

As far as redundancy, there're redundant air speed sensors (3 i think), but they suspect that they all iced up and failed. Once you lose track of air speed at 38k feet, you are in pretty deep shit. Flying too slow = stall. Flying too fast, the plane will actually rip apart. And the margin between flying too fast and too slow at 38k feet is just by a hair. The higher you fly, this margin becomes smaller.

i understand all of this perfectly. GPS and INS don't ice up though. were they running pitot heaters? static ports were likely clear, as it sounds like their altitude readings were accurate and they knew it. all i'm saying is that when i was taught instrument, if one instrument gives faulty readings on either side, don't trust it. use a backup. all 3 of the pilots should have immediately suspected pitot ice given the conditions they were flying in, altitude, and airspeed being directly related to pitot pressure. seems like a classic case to me. according to reports, it seems as if panic played a big role in this accident. being in a lvl 4 storm at FL380 with no obvious accurate airspeed reading would make anyone shit bricks, but with a little diligence, i think this accident was completely preventable.

first, at the stall horn, they pulled up, not pushed down. why? overspeed indications are a lot different than stall indications. mind you, the stall warning systems are separate from the pitot/static system. stall warnings occur when at or near the critical angle of attack (separation of airflow over the wings), not based on airspeed, although level flight at low airspeed will produce a stall obviously. there's another redundancy. from studying air accidents in the past, aeroperu 603 (i said avianca earlier, but meant aeroperu 603) had the static ports taped over. of course everything went haywire, but one of the biggest oversights was that the stall warning is a separate system than overspeed or any other pitot/static instruments. they feared an overspeed and basically stalled it all the way to impact.

second, pitot ice is a lot easier to deal with than static port blockage. just doing a simple descend/ascend parabola would have shown if the altimeter/VSI was functioning properly thus ruling out static port blockage. airspeed seemed to be the only indication not working properly. that's automatically pitots 100% of the time. if they were worried about airspeed, they should always initiate a slow descend first at a power setting that would be considered normal. of course the ASI is going to function more like a VSI when it's blocked, but that's standard knowledge. i know i would personally much rather be headed downhill at FL380 with ASI problems than try to crank it up. not only that, but just glancing at speed from either the INS (as would be required equip. TATL) or GPS groundspeed would have given them the answer they were looking for. i know the pilots knew the approx. wind speed and direction at that altitude. it's hard not to know for any experienced pilot. simple E6B conversion would give you exact information quickly.

third, provided they would have diagnosed to problem, they could have just as easily steered out of trouble, descended, cleared the pitot tubes with pitot heaters and warmer flight levels, and found somewhere to land.

i just think this was a case of taking the wrong evasive action too quickly because of the conditions they were flying in. there are too many redundancies on an airplane as complex as an A330 for an accident like this to happen. i think they got locked on to the ASI's and never ran thru all the appropriate emergency checklists and backups. they had to be alert. i know they probably weren't having casual conversations in a lvl 4 TS. i just think panic set in and everything else was out the window.

[GregTheStig]

It's stuff like this that makes me nervous every time my father flies. He's very experienced and one of the best I've ever been flown by, but still. He basically told me that no pilot would pull up in a stall. Some pilots are better than others, but no airline would send an incompetent pilot across the Atlantic. Now it's going to be interesting to see exactly who or what is to blame for the equipment failure... and how bad Airbus's reputation is going suffer.

[Blake]

Originally Posted by GregTheStig

It's stuff like this that makes me nervous every time my father flies. He's very experienced and one of the best I've ever been flown by, but still. He basically told me that no pilot would pull up in a stall. Some pilots are better than others, but no airline would send an incompetent pilot across the Atlantic. Now it's going to be interesting to see exactly who or what is to blame for the equipment failure... and how bad Airbus's reputation is going suffer.

well my biggest question is were the pitot heaters on? if they were, they why did this happen? did they fail? those tubes are designed to travel through extreme speeds and conditions. the heaters aren't exactly weak either. they'll burn the skin right off your hand if you touch a hot pitot. and he's right about the stalling. not ever once are you taught to pull up if you get a stall warning. flying 101, you learn about stall systems. not a single one of them has anything to do with indicated airspeed. that is done on purpose.

i don't think this will go down as a blemish on airbus as much as it will be pilot error, unless they determine that the pitot heaters failed during flight. it would seem very odd to me if all the pitot heaters failed, as there were at least 2, probably 3 pitots on that plane. i can't fathom that the heaters would all be on the same electrical circuit either, for redundancy purposes. they were either not turned on (pilot error) or something electrical caused the heaters to fail. pilot error seems to be what caused the airplane to stall and likely be sent into an unrecoverable spin.

[M3Bahn]

My guess is they were flying on autopilot and the pitot malfunction put them in unstable flight situation that was made worse by any correction actions.
Wouldn't GPS give a true speed indication as well?

[Blake]

Originally Posted by M3Bahn

My guess is they were flying on autopilot and the pitot malfunction put them in unstable flight situation that was made worse by any correction actions.
Wouldn't GPS give a true speed indication as well?

GPS only indicates groundspeed. GPS only knows how fast a plane is going over the ground based on the satellite triangulation. TAS can easily be derived from that using an E6B, which every pilot should have as part of their flight bag, or arithmetic.

with the pitots being iced over, flying through storms, the atmospheric pressure will change. the blockage will cause the the AIS to read higher during ascent and lower in descent. this is what likely caused the pilots to pull up so severely. they kept seeing the airspeed increase while trying to slow the plane down, thus causing the plane to bleed off almost all the airspeed, sending the plane into an unrecoverable spin. the plane did literally fall out of the sky. if i were to skydive from FL380, it would take me about that long at terminal velocity to hit the ground.

i think that it's also worth mentioning that the envelope between breakup and stall in an a330 at that altitude is really small. this probably added to the panic. unfortunately, they didn't recognize the problem in time and the plane drops like a rock. and good luck recovering that plane from a spin once you've put it in one. it won't happen.

[M3Bahn]

Originally Posted by Blake

GPS only indicates groundspeed. GPS only knows how fast a plane is going over the ground based on the satellite triangulation. TAS can easily be derived from that using an E6B, which every pilot should have as part of their flight bag, or arithmetic.

with the pitots being iced over, flying through storms, the atmospheric pressure will change. the blockage will cause the the AIS to read higher during ascent and lower in descent. this is what likely caused the pilots to pull up so severely. they kept seeing the airspeed increase while trying to slow the plane down, thus causing the plane to bleed off almost all the airspeed, sending the plane into an unrecoverable spin. the plane did literally fall out of the sky. if i were to skydive from FL380, it would take me about that long at terminal velocity to hit the ground.

i think that it's also worth mentioning that the envelope between breakup and stall in an a330 at that altitude is really small. this probably added to the panic. unfortunately, they didn't recognize the problem in time and the plane drops like a rock. and good luck recovering that plane from a spin once you've put it in one. it won't happen.

Graveyard spirals are called that for good reason.
I am wondering if they lost all instruments or at least the artificial horizon and were flying blind which would make more sense but I guess that would show up in black box data.

This shows flight data in a graphic

http://www.flightglobal.com/articles...-attitude.html

[john9]

Originally Posted by Blake

well my biggest question is were the pitot heaters on? if they were, they why did this happen? did they fail? those tubes are designed to travel through extreme speeds and conditions. the heaters aren't exactly weak either. they'll burn the skin right off your hand if you touch a hot pitot. and he's right about the stalling. not ever once are you taught to pull up if you get a stall warning. flying 101, you learn about stall systems. not a single one of them has anything to do with indicated airspeed. that is done on purpose.

i don't think this will go down as a blemish on airbus as much as it will be pilot error, unless they determine that the pitot heaters failed during flight. it would seem very odd to me if all the pitot heaters failed, as there were at least 2, probably 3 pitots on that plane. i can't fathom that the heaters would all be on the same electrical circuit either, for redundancy purposes. they were either not turned on (pilot error) or something electrical caused the heaters to fail. pilot error seems to be what caused the airplane to stall and likely be sent into an unrecoverable spin.

I’m with you.That makes two of us.

[Express]

lots of facts in this thread.

kind of reminds me of the aeroperu crash, but that was human error. what moron leaves the caps on the pitots???

the pilots flying that 757 were very experienced, from what i have read, and in the moment, its tough to think to check gps for speed (even though it should be first hand)

pilot error is a common yet unfortunate event. why didn't the pilots in the american crash in columbia retract the speed brakes? if they did, that plane never would have hit the mountain.

[Blake]

Originally Posted by express705

lots of facts in this thread.

kind of reminds me of the aeroperu crash, but that was human error. what moron leaves the caps on the pitots???

the pilots flying that 757 were very experienced, from what i have read, and in the moment, its tough to think to check gps for speed (even though it should be first hand)

pilot error is a common yet unfortunate event. why didn't the pilots in the american crash in columbia retract the speed brakes? if they did, that plane never would have hit the mountain.

well the aeroperu crash was actually faulted by MX and pilot error. if you remember, the static ports were taped over during a cleaning of the fuselage. the problem wasn't spotted during pre-flight because the tape was the same color as the fuselage paint. the pilots were obviously highly confused because every possible warning was going off. static port problems are much hairier than pitot problems, but i don't have to tell you that. in the case of aeroperu, they had help from ATC, who were able to give them basic information about their altitude and groundspeed. they didn't heed the advice of ATC and kept making the problem worse on their own.

i know it can be hard to diagnose the problem as it's happening, but there are so many accident case studies out there that should be at least considered in an emergency situation. that's why we studied them in our AV safety classes.

it's a sad tragedy, but yet another lesson we pilots have to learn from. i can't say what i would do given the circumstances, but i do know i wouldn't cut the power and pull up. that goes completely against everything i've ever been taught. i do know a diligent constant scan of all flight instruments, including GPS, could have led to much better situational awareness and probably discovering the discrepancy a lot sooner. like i said, i'm guessing they fixated on the ASI's and took the wrong actions out of haste, sealing their fate.

[Express]

great point. forgot that it was the static ports.. you are right!

i hate to change the subject, but a friend of mine was the co pilot of the legacy jet that clipped the gol 737 in brazil. we have had some long conversations about it, and as horrible of a tragedy as it was, i feel sympathetic for him and the pilot. its a terrible situation. they were just sentenced to community service in the USA, but he told me its not over since the government will appeal it..

every airplane accident is a tragedy, but unfortunately, thats how we learn to try and avoid the next one.

[M3Bahn]

They may have thought they were over-speeding and pulling up nose trying bleed off airspeed because thought they were in a high speed stall?

This article discusses the "coffin corner" which I have never heard of before.

The "Coffin Corner" and a "Mesoscale" maw

First, a bit of aerodynamics: The doomed Airbus A-330-200 was flying ever so close to its maximum altitude, in a zone pilots call the "Coffin Corner." It refers to the edge of the so-called "flight envelope" of an aircraft.

http://www.reuters.com/article/2009/...090608?sp=true

[Blake]

Originally Posted by express705

i hate to change the subject, but a friend of mine was the co pilot of the legacy jet that clipped the gol 737 in brazil. we have had some long conversations about it, and as horrible of a tragedy as it was, i feel sympathetic for him and the pilot. its a terrible situation. they were just sentenced to community service in the USA, but he told me its not over since the government will appeal it..

i don't remember studying that accident, as that happened after i was in school, but i just read up on it. crazy you know the actual copilot. is he still flying? looks like a mix of pilot error, but a majority of ATC error. why was the TCAS off? just forgot to switch it on?

[vioaltec]

what perplexes me is that on board the aircraft there are two attitude systems in the primary instruments that depend on the pito tubes and also an independent system called ISIS that display the same data amongst the other 2. In other words a system failure should be highly impossible. I wonder what was the a330's angle of attack when it was going through this?

[scollins]

I think pilot inexperience played a part as well:
Information according to Air France press communiqué:
Pilot in Command: 11.000 hours total flight experience, 1.700 hours on A330/A340 aircraft
1st Copilot: 3.000 hours total flight experience, 800 hours on A330/A340 aircraft
2nd Copilot: 6.600 hours total flight experience, 2.600 hours on A330/A340 aircraft

1st copilot is in the left seat at time of incident. 3,000 ttl hours is not a lot for an ATP, and 800 hours in type isn't that high either.