AirAsia plane missing between Indonesia and Malaysia

[North Shore]

An article about a deep stall in a 727: http://www.seattlemag.com/article/seven ... test-pilot

[ettw]

Very good read!

Thanks for the post.

ETTW

[Eric Janson]

Here's another incident where a rapid climb developed on an A340 - again I'm not saying this is what happened with Air Asia.

http://www.aaib.gov.uk/cms_resources.cf ... 6-2001.pdf

[pdw]

About the middle of page 12 of your reference there .. the "6000' minute" rate of climb shared in a few of these events is being referred to as a "zoom climb". The "wing flex" witnessed by the other aircraft shows the sporadic nature of this type of launch into a 'high rate' from level.

[mbav8r]

http://www.bbc.com/news/world-asia-34972263
http://www.cnn.com/2015/12/01/asia/air- ... sh-report/

[GyvAir]

Impressive, that they could pinpoint a bad solder joint after all that metal hit the water and remained submerged for a considerable length of time.

On a side note, I do miss PDW's musings!

[CpnCrunch]

AF447 all over again by the sound of it.

[boeingboy]

Sorta - but not really.

You never, ever pull the FAC C/B's in flight. It takes at least 90 sec for them to reboot after resetting the breaker.

[CpnCrunch]

I was referring to "a prolonged stall condition that was beyond the capability of the flight crew to recover". It's only different from AF447 in how they got themselves into that position (removing the CBs vs iced up pitot tubes).

[FICU]

The crew tried to fix the problem by resetting the computer system, but this disabled the autopilot. They then lost control of the plane.

This will continue to happen over and over with the lack of experience and fast tracking of cadet pilots(can we call them pilots?) into the right seats of airliners, especially Asian budget and low cost airlines.

[TheStig]

The crew tried to fix the problem by resetting the computer system, but this disabled the autopilot. They then lost control of the plane.

This will continue to happen over and over with the lack of experience and fast tracking of cadet pilots(can we call them pilots?) into the right seats of airliners, especially Asian budget and low cost airlines.

For non-Airbus types, this would be akin to driving on the highway and trying to fix a radio problem by turning your car off while still driving. There's a big difference between doing a reset at the gate and doing one while flying. They made a very minor issue into a major one. Basic airmanship, never attempt to reset anything inflight related to the fuel system, flight controls, or engines, unless you absolutely need it.

[Cliff Jumper]

Basic airmanship, never attempt to reset anything inflight related to the fuel system, flight controls, or engines, unless you absolutely need it.

Basic airmanship might be a bit of a stretch, no?

[Meatservo]

I find myself wondering if this business of "averaging" the inputs of the two control columns is all that clever. I mean I guess it is, since much cleverer men and women than myself have designed the system and put up with it for a long time, but still, I find it a bit disturbing. I tried to picture myself in manual control of an aeroplane, which was easy because that would describe most of my flying up to this point. Then I tried to imagine thinking I was in manual control of an aeroplane but having the aeroplane manoeuvre in a different way than I was used to seeing considering my control inputs. I am sure most experienced pilots have an extremely hard-wired expectation that when they move the column in one way or another, the plane itself will move in the way they have come to expect. For it not to do so, because the other pilot is also moving his completely unconnected column in another direction, must be extremely disorienting.


There are aeroplanes in which the right elevator and aileron are directly connected to the right column, and the left surfaces to the left column, respectively. The columns are then under normal circumstances, also connected together, for pretty goddamn obvious reasons. I think I like that system better than the Airbus one.

I hope my comments aren't merely an artifact of my complete unfamiliarity with this type of aircraft. I'm just as glad I don't fly one, frankly.

In Canada, they tend to be flown by two experienced pilots who not only can fly a plane but have more tendency not to panic and start heaving the stick back and forth when something goes wrong. But in other countries, one experienced pilot is often paired up with a brand-new guy who cannot possibly have developed any kind of reflex for proper aeroplane handling. Then they put this pair in a plane that encourages very little flying-skill development AND they give them a pair of control columns that aren't connected! Seems like a "root cause" to me, more than the stupid circuit-breaker snafu OR the broken circuit board!!

[boeingboy]

Several seconds later the flight data recorder recorded the failure of the FAC1, 17 seconds later the failure of both FAC1 and FAC2, the FBW reverted to Alternate Law, the aircraft rolled left up to 54 degrees of bank. Nine seconds after both FACs failed the right side stick activated, the bank angle reduced to 9 degrees left and rolled back to 53 degrees left bank angle, the side stick was mainly pulled back, the aircraft pitched up and climbed reaching up to 11,000 feet per minute rate of climb. 34 seconds after both FACs failed a stall warning activated, briefly ceased for 1 second after 4 seconds, then remained active until end of recording.

The standby airspeed indicator recorded a lowest airspeed of 55 KIAS then settled at around 140 KIAS until end of recording. The highest altitude was recorded at 38,500 feet and a left bank angle of 104 degrees, the aircraft subsequently lost height at a rate of descent up to 20,000 fpm.

Descending through about 29,000 feet the wings were level, the airspeed was between 100 and 160 KIAS, the angle of attack was at approximately +40 degrees, the stall warning remained active and the aircraft lost height at about 12,000 fpm until end of recording.

The flight data recorder stored the last sample at a radio height of 118 feet, the airspeed was 132 KIAS and the rate of descent 8400 fpm.

With respect to the left roll the NTSC analysed: "After electrical interruption the autopilot disengaged and the ruder deflected at 2° then the aircraft rolled to the left without pilot input with a rate of 6° per second. This rate of roll was two times faster than normal roll rate operation. The SIC who acted as Pilot Flying responded 9 seconds after the autopilot off when the roll angle had reached 54°.

During the stall warning activated, the right side stick was at neutral then moved forward for two seconds. It caused the AOA decreased below 8°, and the aural stall warning stopped. "The first left side stick input was at 2317:03 UTC for 2 seconds, then 15 seconds later another input for 2 seconds, and at 2317:29 continued in dual input until the end of the recording. The FDR recorded at 2317:15 UTC the aircraft pitch reached 24° up. The PIC commanded „pull down...pull down‟ and at 2317:17 UTC the FDR recorded second Stall Warning. Following the command „pull down...pull down‟ the FDR recorded the SIC side stick backward input increased. The average of the side stick inputs recorded on the FDR since the A/P and A/THR disengaged until the aircraft encountered the second stall warning indicated that the SIC was pulling almost full back input while the PIC was slightly pushing nose-down. The sum of both side stick inputs commanded nose up pitch. The pitch up input resulted in the AOA reaching a maximum of 48° which was beyond the flight director envelope and the flight director would have been disappeared from the PFD. The pilot training and the aircraft system were intended to avoid stall. The condition of AOA 40° as recorded on the FDR was beyond any airline pilot training competency as they never been trained or experienced. The degraded SIC performance and ambiguous command of the PIC may have decreased the SIC‟s situational awareness. Consequently, the SIC did not react appropriately in this complex emergency situation. This resulted in an aircraft upset from which recovery was beyond the procedures and philosophy of training that was provided to flight crew and the increasing difficulty of aircraft handling as the result of the rudder deflection which provided roll tendency."

Maybe the biggest problem was the Captains command that appears was not spoken in very clear english. It probably completely confused the FO who was already stressed out. Even so - I still can't see why the Captain did not have full fwd stick input.

[cgzro]

Maybe the biggest problem was the Captains command that appears was not spoken in very clear english. It probably completely confused the FO who was already stressed out. Even so - I still can't see why the Captain did not have full fwd stick input.

If the sticks were linked there would be no misunderstanding. No talking required. I have spent a lot of time in unusual attitudes with linked sticks and I always know what the other person is doing instantly. If you removed that feedback the situation would be made much more dangerous.

Averaging, take over buttons and light arrows are silly.

Now every time an accident occurs where non linked sticks seems involved the Airbus pilots jump in to defend them based on proper training. Fair enough, but when one of the guys is doing the wrong thing clearly training has failed and a system that lets the captain know instantly whats up cant possibly be argued against but for some reason it will be.

[Meatservo]

Now every time an accident occurs where non linked sticks seems involved the Airbus pilots jump in to defend them based on proper training. Fair enough, but when one of the guys is doing the wrong thing clearly training has failed and a system that lets the captain know instantly whats up cant possibly be argued against but for some reason it will be.

Yes, that's just the point I was trying to make in my last post. Airbus seems to be very safe for experienced pilots who remain calm and have some flying ability. These accidents where you hear of the one stick going one way and the other going the other way, and everybody getting disoriented because the plane isn't doing what they are telling it with their separate controls, also seem to involve a crew composed of one experienced guy and one or more low-time products of a "cadet" program who were taught that hand-flying is an obsolete skill.

It always seems to boil down to the captain getting thoroughly disoriented because the plane isn't reacting to manual control inputs the way it should while, out of his line of sight, the dangerously inexperienced copilot is busy cranking away at the stick like he's trying to mix a light fluffy cake batter, like a blind dick in space thrusting in infinite directions hoping to find pay dirt.

They're going to react to this by dreaming up some more complicated control subroutines in order to demonstrate a perfunctory, superficial concern for safety, and continuing to pretend they don't realize that the solution is to crew aeroplanes with people who actually know how to fly aeroplanes. Because that would cost a little bit of money.

[FICU]

3 words by the Captain could have saved that ship... "I have control" or a few more... "get your hand off the f*ckin' stick!"

Another case of 2 pilots fighting each other unknowingly and an aircraft system design that allows it to happen and causes an aircraft to be destroyed.

[cgzro]

People dont always react properly in tense situations. Some people freeze up and dont give you the stick back. At the point where unlinked sticks add to the confusion training has already broken down.
I have had very experienced pilots try to level wings with aileron despite telling them not to before and during and a solid grip on thr stick was the only way to prevent it. Sudden forward stick fir spins is another where feeling it is essential to preventing it.

I am reasonably certain you could rig up a light two seater aerobatic plane with digital unlinked sticks and easily demonstrate how two pilots can screw up. Throw in noise, smoke darkness whatever and you have a recipe for confusion.

I fail to see why the weight savings are worth it given the crashes where confusion has at least played some part.

[Rockie]

There is a warning given when both sticks are manipulated at the same time, and the Captain doesn't have to say "I have control" or wrestle the other pilot for control of the ship. There is a red button on each stick used to disconnect the autopilot that can also be used to lock out the other stick. The Captain in this case could have used it, recovered the airplane while the FO flailed around with his stick all he wanted, and then explained the situation once they were assured of living. That's why it's designed that way.

[Meatservo]

If there is an identical red button on the other stick, what happens if they're both pressing it?

[Rockie]

If there is an identical red button on the other stick, what happens if they're both pressing it?

There is. If both pilots press the button the last pilot to press it gets priority. If the button is pushed for more than 40 seconds the other stick is latched out and the pilot taking priority can let go of the button, however a latched out stick can be reactivated at any time by momentarily pushing the takeover button on either stick.

I guess it becomes a battle of thumbs if both pilots are determined to control the airplane. Then the yelling starts and you haul out the fire extinguisher to clock the guy trying to kill you.

[FICU]

No failsafe designed into the system allows airplanes to crash. Not good in the wrong hands.

[TomC]

There is a warning given when both sticks are manipulated at the same time, and the Captain doesn't have to say "I have control" or wrestle the other pilot for control of the ship. There is a red button on each stick used to disconnect the autopilot that can also be used to lock out the other stick. The Captain in this case could have used it, recovered the airplane while the FO flailed around with his stick all he wanted, and then explained the situation once they were assured of living. That's why it's designed that way.

As I understand it, the "Dual Input" aural message didn't sound as it was suppressed by the "crickets" and the "Stall! Stall!" warning, which sounded for the whole time they were in the descent.

[Eric Janson]

Averaging, take over buttons and light arrows are silly.

Now every time an accident occurs where non linked sticks seems involved the Airbus pilots jump in to defend them based on proper training. Fair enough, but when one of the guys is doing the wrong thing clearly training has failed and a system that lets the captain know instantly whats up cant possibly be argued against but for some reason it will be.

The issue isn't non-linked side sticks - the issue is that a crew can't fly the aircraft safely after a relatively minor failure.

Loss of autopilot and reversion into alternate law should not result in a rapid climb followed by a stall and crash.

[complexintentions]

The issue isn't non-linked side sticks - the issue is that a crew can't fly the aircraft safely after a relatively minor failure.

Loss of autopilot and reversion into alternate law should not result in a rapid climb followed by a stall and crash.

Errr...didn't you say you had flown extensively in Asia? (That's tongue-in-cheek, in case that isn't apparent).

I agree completely, though. I'm not interested in bashing this design philosophy or that. The industry just has to start placing more emphasis on keeping handling skills current. For all of the flaws of my current employer, one thing I salute them for is scheduling regular extra sims solely to practice hand-flying recovery from all kinds of unusual attitudes and upsets. They're smart enough to be shit-scared of this happening to them.