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I'd read the Air France story before but re-reading it again, the most terrifying bit is the fact the passengers would probably have been unaware anything was going on and the first they would have known was when they hit the water. 🙁
torsoinalake - MemberNormally you would have differential inputs between the sticks all the time. i.e. Only the person that is flying the plane is making inputs.
Yes, but presumably in that normal situation, one would be in the 'home' position with everything in a 'no input' state? So that stick wouldn't be trying to influence the control of the aircraft?
I meant if one stick was reading 'stick being pulled all the way back' and the other was reading 'stick being pushed forwards and a bit over to the left'......for example....should the computer brain not give a warning of something along the lines of 'are you aware that you're pulling my controls in different directions; is this intentional or are you being stupid???'
There is nothing wrong with Aircraft system design. There are mistakes made by humans.
You are just contradicting yourself there. All the systems, electrical, mechanical, whatever are designed by humans and humans make mistakes. You are entitled to your opinion and so am I but there is no need to be insulting.
The loss of an aircraft is not the only way to gauge poor design/mistakes. Aircraft manufacturers may employ some of the best pilots in the world, they may have some of the best engineers and technicians too, but the end users may not or they may be having on off-day or the conditions may be far from ideal and this needs to be considered somewhere in the software, electronics, mechanisms, structure, operating manual, maintenance manual etc etc. Every aircraft has mistakes,fact of life. Correcting them is problematic but the engineering is the easyish bit, the real fun is with admitting there is a problem and getting the money.
Air crashes are 99.99999999999999% down to pilot error. That is a FACT. The others are down to factors outside of the Aircraft designs remit - choice to fly in bad weather, terrorism etc. Even when the A320 flew through a flock of geese and landed in the hudson, the aircraft came down safely with no loss of life. In a properly trained, properly operated environment, they are safe. When short-cuts are taken, thats where problems happen. There is no surprise that a lot of these issues are with the asian operators.
Your comment makes absolutly no sense. With 10,000 aircraft and millions and millions of flight hours, there have been around 15 aircraft crashes NONE of which were down to poor aircraft design.
NONE of which were down to poor aircraft design.
Someone's forgetting the [url= http://dh-aircraft.co.uk/aircraft/dh106/comet1/inquiry/ ]Comet[/url] and it's square windows.
This was a long time ago, but, still.
EDIT - or are you referring to Airbus alone? They're still capable of making [url= http://theconversation.com/the-airbus-a380-wing-cracks-an-engineers-perspective-5318 ]mistakes [/url]in design, like all of us. To forget this would be, in my view, an error.
Sorry, i thought we were talking about modern aircraft flying today.
I meant if one stick was reading 'stick being pulled all the way back' and the other was reading 'stick being pushed forwards and a bit over to the left'......for example....should the computer brain not give a warning of something along the lines of 'are you aware that you're pulling my controls in different directions; is this intentional or are you being stupid???'
I don't know enough about it, but from reading the Popular Mechanics article, you can have inputs on both sticks. Which doesn't imply something bad is happening, as long as the plane continues in normal flight. However, an alert was sounding in the form of the stall alarm (my bold):
[i]As the stall warning continues to blare, the three pilots discuss the situation with no hint of understanding the nature of their problem. No one mentions the word "stall." As the plane is buffeted by turbulence, the captain urges Bonin to level the wings—advice that does nothing to address their main problem. The men briefly discuss, incredibly, whether they are in fact climbing or descending, before agreeing that they are indeed descending. [b]As the plane approaches 10,000 feet, Robert tries to take back the controls, and pushes forward on the stick, but the plane is in "dual input" mode, and so the system averages his inputs with those of Bonin, who continues to pull back. The nose remains high. [/b]
02:13:40 (Robert) Remonte... remonte... remonte... remonte...
Climb... climb... climb... climb...
02:13:40 (Bonin) Mais je suis à fond à cabrer depuis tout à l'heure!
But I've had the stick back the whole time!
At last, Bonin tells the others the crucial fact whose import he has so grievously failed to understand himself.
02:13:42 (Captain) Non, non, non... Ne remonte pas... non, non.
No, no, no... Don't climb... no, no.
02:13:43 (Robert) Alors descends... Alors, donne-moi les commandes... À moi les commandes!
Descend, then... Give me the controls... Give me the controls!
Bonin yields the controls, and Robert finally puts the nose down. The plane begins to regain speed. But it is still descending at a precipitous angle. As they near 2000 feet, the aircraft's sensors detect the fast-approaching surface and trigger a new alarm. There is no time left to build up speed by pushing the plane's nose forward into a dive. At any rate, without warning his colleagues, Bonin once again takes back the controls and pulls his side stick all the way back.
02:14:23 (Robert) Putain, on va taper... C'est pas vrai!
Damn it, we're going to crash... This can't be happening!
02:14:25 (Bonin) Mais qu'est-ce que se passe?
But what's happening?
02:14:27 (Captain) 10 degrès d'assiette...
Ten degrees of pitch...
Exactly 1.4 seconds later, the cockpit voice recorder stops.
[/i]
It's such a catastrophic failure in protocol. Hard reading again.
On a par with the Flight Engineer on the Air France Concorde that crashed shutting down a working engine immediately before take off.
Very unprofessional of Indonesians (I think) to leak partial information. Plane flew into a serious storm, lots of bad things can happen. Recovering from a stall in an airliner may not be straight forward, particularly if aircraft becomes inverted. Pilots and airlines are well aware of this which is why they try and avoid such storms, real issue here for me is that Air Asia did not have permission to fly that route on that day, perhaps the reason is that the airspace is too crowded to allow planes to be re-routed in the event of bad weather.
Air crashes are 99.99999999999999% down to pilot error
That's certainly what the manufacturers of very expensive planes want us to believe. I have had more than a few conversations about this with an ex airliner pilot/trainer (previously flew military aircraft) with 40 years experience.
Vast difference between fact and feeling.
Just so I can understand... how many actual real life pilots are contributing to this?
1.
I have played Microsoft Flight Simulator, and have been in the cockpit of a commercial airliner (when I was about 8, it made me feel airsick). Oh, and I have been in the cockpit during the landing of an SAA flight, a turboprop on a domestic route - that was cool. Jumped out of a Cessna on a few occasions. My Dad used to work for BA. My grandads were both in the RAF.
So it's in my blood really.
Air crashes are 99.99999999999999% down to pilot error.
That's a very simplistic view. What caused the pilot error? Maybe poor design of the controls?
If the pilot misreads the instruments, surely the instruments should be better.
(I am not a pilot.)
Vast difference between facts and feelings / maybes
I will actually change my statement a little bit, the persons who are responsible for the training of the pilots are equally as accountable as the pilots are for their mistakes.
torsoinalake - MemberI don't know enough about it, but from reading the Popular Mechanics article, you can have inputs on both sticks. Which doesn't imply something bad is happening, as long as the plane continues in normal flight. However, an alert was sounding in the form of the stall alarm
Exactly. So the stall warning was sounding and one bloke (the captain) was trying to get the nose of the plane down by pushing the stick forward. At the same time, the most inexperienced of the crew is (for reasons that seem to defy logic) still pulling back on the stick - so the system takes something like 'the average' of those inputs. The captain only realises that the co-pilot has his stick fully back (preventing a nose down attitude to regain speed, and presumably with it, lift) when the co-pilot tells them that is what he is doing. By then it's too late to prevent the crash.
If the software had said 'HELLO!! Are you supposed to be pushing my sticks forward & backwards at the same time??', then the captain or the other co-pilot might have realised earlier that the inexperienced bloke was doing stuff he shouldn't have been.
I'm sure there's a good reason for having the sticks set up like that. I can't think what that good reason is though. Would be interested to know.
Maybe the designers figured that with all of the conventional instruments and alarms that would indicate a problem, another warning was probably superfluous.
Edit: But that is another 'maybe' as LHS points out. Anybody got the number for Airbus?
The main problem on the air france crash was the crew ignored the stall warning (which at one point was ignored for a minute). Now a lot of the report does state pilot training which i do agree with. This was an inexperienced, disfunctional flight crew presented with a problem that they weren't prepared for.
AIUI that is not correct. The stall warning actually stopped because they were too steep (a function of being in alternate law due to the pitot issue and the computer not believing what it was being told). Basically the pilot did exactly the wrong thing (pull back on the stick) but to him it was the right thing as the alarm stopped. The alarm kept restarting but pulling back on the stick stopped it. The plane was in stall the whole time.The main problem on the air france crash was the crew ignored the stall warning (which at one point was ignored for a minute)
but to him it was the right thing
How was it the right thing to him to pull back on the stick when hearing a stall warning?
Because pulling back on the stick caused the warning to stop.
That's not the right thing to do and would not have been part of any training. Pulling out the wires to the audible warning speaker would have made the alarm stop, doesn't mean you should do it.
Just so I can understand... how many actual real life pilots are contributing to this?
@Drac, I've flown planes and gliders a bit not solo though, I've been on a simulator at Heathrow, but fair point entirely I am no pilot !
I'd read the Air France story before but re-reading it again, the most terrifying bit is the fact the passengers would probably have been unaware anything was going on and the first they would have known was when they hit the water.
@Boardin, I suspect that's not actually true. It's a bit like saying "died instantly" in things like car crashes. I've been on a flight which dropped violently and my drink hit (mostly empty) the roof, it was pretty clear something was happening. People have died on flights not being strapped into their seats and breaking their necks when plan drops violently causing them to hit the roof.
The fact the plane was rising does not necessarily mean he was pulling back violently on the stick, it could have been a massive updraft. He was probably in the middle of some serious stormy weather. He could have been trying to rise above it, he had asked to climb and been denied permission.
Its all complicated as the stall speed increases as you climb as the air get's thinner, typically when you are climbing your speed drops, there are many factors in this. We don't have anything like all the black-box data and analysis yet.
He didn't know what to do for whatever reason so did something that, to him, appeared to work.That's not the right thing to do and would not have been part of any training
IMO it is due to pilots learning how to operate an aircraft rather than fly a plane. I wonder how many would be happy to fly a big plane on basic instruments and what they see out of the window. The Hudson pilot was an ex fighter pilot and active glider pilot. That helped a lot. Go and look at the stats for successful water landings.
jambalaya - I think there's a mixture of incidents being talked about here....
the talk about the 'stick being pulled back' is relating to the Air France crash, I think, rather than the latest Air Asia incident.
Unless I have misunderstood....
Its all complicated as the stall speed increases as you climb as the air get's thinner,
is that particularly if you're in the middle of a storm?#
#Of course I am qualified to my opinion due to a childhood spent reading Flight magazine throughout the 70's and piloting remote control gliders, a Dad who managed commercial aircraft maintenance (could also fly light aircraft) and as a member of STW 😳
I assume pilots must think aircraft are, in general, pretty safe.
It will be a combination of factors not just one error on its own that led to the crash.
As a current Airbus driver, I have some ideas as to potential issues but would rather wait until the experts have released their facts.
The 'Bus flies just like any other high performance jet; it has in-built protections, however if you lose those (like AF447) it flies just like a regular airliner. High altitude stall recovery requires subtly different handling to the low altitude stall recovery but the fundamental basics (reduce AoA until lift is recovered) remain the same.
RIP to those involved and I'm sure that we as an industry will sadly learn lessons from this tragic event, however it's a sad fact that most accidents have happened before and no doubt will happen again.
The Hudson pilot was an ex fighter pilot and active glider pilot.
Puts me in mind of [url= http://hawaii.hawaii.edu/math/Courses/Math100/Chapter1/Extra/CanFlt143.htm ]this Canadian Airlines story[/url]. The pilot had a lot of glider experience...
The avoidance of disaster was credited to Capt. Pearson's "Knowledge of gliding which he applied in an emergency situation to the landing of one of the most sophisticated aircraft ever built."
Some interesting reading here... http://www.aaib.gov.uk/publications/bulletins/january_2015/cessna_525a_citation_cj2___n380cr_.cfm
A near accident over the UK where a high altitude stall results in loss of control and athe aircraft rolls 3 times and gets damaged during a high G recovery.
@Boardin, I suspect that's not actually true. It's a bit like saying "died instantly" in things like car crashes. I've been on a flight which dropped violently and my drink hit (mostly empty) the roof, it was pretty clear something was happening. People have died on flights not being strapped into their seats and breaking their necks when plan drops violently causing them to hit the roof
I did consider that, but when you read the transcript the crew does debate whether or not they were climbing or ascending, so I do wonder how perceptible the altitude change would be to the passengers.
If I'm understanding it correctly, the plane was flying at an angle (this is the angle of attack?) that would normally result in gaining altitude, yet it was actually falling. If the crew couldn't pick up on that sensation of descending, the passengers, many of whom would have been sleeping, were hopefully oblivious to it all, and their deaths would have been quick and merciful 🙁
One thing missing from the comments I've read (so far) re. the Air France incident is that the commercial pilot flight training stall recovery technique is not suited to recovering an aircraft from a stall at high altitude - the assumption in the training is that you're only going to stall on landing approach.
The training therefore is to increase thrust and apply forward stick. Due to the location of engines on most airliners this is not the best way to deal with a stall at altitude - the thrust will make the aircraft nose up, combined with thin air that will not give as much of a force from control surface movements and an aircraft outside of its intended design envelope.
Test pilots are trained to nose down, regain airspeed/angle of attack then throttle up. This is done in test flights for type approval.
No idea if this is really relevant to the recent incident (or whether it was relevant to Air France, in the end)
@stumpy got it
@mike thanks for that input from someone who actually flies one of these things
@Darc sounds like we are of a similar age with a similar background, I am a hoarder to still have my Futaba gear in the loft
@philjunior + 1, as I understand it you can get a commercial airliner into a situation into which there is no recovery full-stop (true with pretty much all aircraft as far as I know)
Phil,
As I mentioned above, high altitude stall recovery requires a subtly different technique to low altitude recovery. We're trained in both as are most UK operators, I'm sure.
Jamba,
A high alt stall should be recoverable. Low alt stall will depend on how much altitude you have available, reaction time, weight etc. But in essence, you should be able to recover from them all within reason. The key is to recognise the symptoms of the approaching stall and never get there in the first place. I'm lucky in having stalled aircraft countless times as a student and instructor on basic and high performance types at all sorts of altitudes. Many pilots are given a commercially-driven training package (we all like cheap fares don't we?) and have had limited exposure of the joys of stalling.
A storm cell might (if you've climbed to a level where your margins are reduced-"Coffin Corner") bring on a stall situation very rapidly. That's why, especially given the intensity of the storm as featured in the press, [i]climbing[/i] to avoid a storm cell isn't a great idea. Plus some very active storms will exceed the Max Altitude of most aircraft.
Better to give them respectful lateral separation, ideally >20nm.
@mikertroid, how much of a dive would you have to put the plane in at high altitude? Proper nose down, rapid descent, screaming passengers or more gentle?
mikertroid - good to know.
Bob,
At height and if you've got it fully stalled it could be in the region of 40-45° ND (all depends on the conditions of the day etc). You pitch until the symptoms stop so there's no actual number you're aiming for unless you're using AoA gauges.
It's very easy to go back into the stall if you try to regain pitch too soon and if you give it full thrust due to the pitch up effect of under slung engines. You'd get a few screams for sure and you'd lose a few thousand feet. But you wouldn't (unless flying over Everest) hit the deck.
Many pilots are given a commercially-driven training package (we all like cheap fares don't we?) and have had limited exposure of the joys of stalling.
We did loads of stall training in both powered and glider aircraft as cadets and actually stall turns in powered craft are a cool and easy-to-master aerobatic move.
I found flying by instruments more difficult than flying on feel and actually in gliders we were specifically discouraged from using instruments.
One tactic we used to use in powered craft was having two cadets up in the air together and doing a mock dogfight or just a "follow the leader". Once you're concentrating on the other aircraft the control systems come much more easily; you fly by feel and reaction rather than looking at instruments.
Crazy-legs
That's great that you've had that experience. Many Airline Pilots don't.
Stall turn isn't a stall however. It's a misnomer. However you can stall (and spin) off them if you don't get it right!!
I'm still bemused by the general, knee jerk reaction to these events - blaming the pilots.
If the Air France Aurbus did not have faulty pitot heads ( which I believe the manufacturer was fully aware of), then the crew's limitations wouldn't have been so painfully exposed.
So let's take a step back - if those pitot heads didn't ice up, would the aircraft have crashed?
It's so, so easy to pontificate from the safe comfort of a computer keyboard.
Trek
I'm sure they were placed in a grim situation. I don't think anyone in the industry mocks them. However there was nothing wrong with the aircraft that prevented its continued flight.
The pitot heads iced up, then started working again once they had de-iced. Not sure that constitutes faulty.
torsionalake, they gave duff information - how much more faulty do you want?