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I thought the whole point of carefully calculating the load plan / weight and ballance was so that an aircraft (as well as flying efficiently) could naturally recover from a stall...? This one seems to have stalled at 32000ft and simply dropped like a stone.
Incidentally:
Citing radar data, Mr Jonan said: "The plane, during the last minutes, went up faster than normal speed... then it stalled.""I think it is rare even for a fighter jet to be able to climb 6,000ft per minute," he told a House of Representatives commission.
[url= http://www.bbc.co.uk/news/world-asia-30902237 ]Sauce.[/url]
A quick google shows the Eurofighter as having a rate-of-climb of around 62000ft/minute. Even an old Jaguar could climb 19000ft/minute.
Does seem similar to the AirFrance crash over the Atlantic, another Airbus avoiding a storm...
If I can recall there were several documentaries regarding instances of planes stalling that resulted or started with immediate climb then dive straight down.
They really need to sort out this stalling thing as apparently the computer system on board cannot understand the sudden change, too much conflicting information, so shut down in order to reboot but failed (too slow to reboot).
😯
The Air France case was 100% pilot error - they crashed the plane whilst in full control, just got very confused about what they were doing (climbing rather than diving to regain lift).
http://en.wikipedia.org/wiki/Air_France_Flight_447#Final_report
The best thing to do is to wait until the all data has been analysed before speculating.
Thought the climb rate of a Normal jetliner was around 2500/3000ft per minute at take off then down to 1500ft per minute. And keeping the speed above 200 kts. Someone's not set the autopilot right or it's had a catastrophic hissy fit.
Yes, all to similar to the AirFrance crash for my liking. One of the biggest issues were frozen pitot tubes, giving the pilots a false appreciation of their predicament. A dodgy altimeter may have prevented the pilots from appreciating firstly their rate of climb, and subsequent rate of descent. In other words the guys may not have realised the consequences of their actions till it was too late. Very sad situation.
The best thing to do is to wait until the all data has been analysed before speculating.
Life would be very dull without speculation.
Watch the brilliant channel 4 documentary on the Air France flight. We don't like to think this, but human error applies to airline pilots too. And sometimes fairly minor events add up to a catastrophic end result
It was aliens. Their tractor beam almost got the plane out of the atmosphere, but it was not at full power after stealing that Air Malaysia plane had caused the batteries to go a bit flat.
Speculation.
Since it's been announced by the Indonesian Transport Minister, to a parlimentary hearing, I struggle to believe it's based purely in conjecture.
Lots of these rate of climb figures are at sea level, the rate drops off a lot as you get higher.
Duffer what did he say. Does it make sense?
Pitot tubes did cause a problem for the Air France but as I have said before in my eyes the fault lies squarely with the pilots. It is something they are trained to deal with from day 1 and they caused a lot of needless deaths.
I do have a lot of criticism for Airbus and the general aviation industry for stupidty in design of aircraft systems. In this case an angle of attack indicator slapped on the instrument panel would have saved the aircraft. Sometimes humans just need to be fed information and not need to infer it.
Would it still have stalled if it had been on conveyor belt?
Only if it had taken off first, which it couldn't have if it had been on a conveyor belt obviously
Pitot tubes didn't cause a problem in the AF crash, just the pilots not realising what was going on and taking appropriate action.....for a good 30 minutes long after the pitot tubes came back on line. They simply ceased to fly the aircraft. There is an angle of attack indicator on aircraft, the artificial horizon.
As they were flying in some pretty dirty weather, and climbing to try to avoid even greater turbulence, could the sudden rate of climb be caused by a violent updraft? Cu. Nim. clouds have quite extraordinary up-and-downdrafts which can chuck very large aircraft about.
Pitot tubes did cause a problem for the Air France
If I remember correctly it/they did freeze but actually started working correctly again well before the crash.
Air France was basically caused by the co-pilot losing it and continued climbing even when the computers was telling him to dive. When the pilot returned to the cockpit and took over the controls and tried to dive the co-pilot was still trying to climb and was overriding the pilots input.
I do wonder if the outcome of this enquiry is going to be the same?
edit: beaten by wobbly
Andyl - not sure you can lay that with the plane. To my mind it was the pilots not flying the plane - high altitude, they throttled down and then just pulled back on the stick while trying to work out what the computer was doing. Basic airmanship? (I'm talking about AF 447 here).
The pitot tubes caused [b]A[/b] problem. It should have been a minor one.
As for atifical horizon you need to read this:
oneoneorange - you need to read my first sentence again:
"Pitot tubes did cause [b]a[/b] problem for the Air France but [b]as I have said before in my eyes the fault lies squarely with the pilots[/b]."
The pitot tubes caused [b]a[/b] problem. They set of a long string of incompetence but it was something that they were trained to deal with, or should have been, and they should not have let the situation get to the stage the aircraft was unrecoverable.
IIRC they were actually on full throttle, engines completely maxed out, but pointing up at 35-40 degrees. A fighter can climb using the massive excess thrust in it's engines vs the weight of the aircraft, an airliner does not have that option.
Yes agreed with that - I don't agree though that re-designing the systems /instrument panel would have necessarily saved it though. I personally doubt it would, but that is pure opinion.
They did say on the radio just before that it may have been an updraft produced by the storm, because to climb that fast would really be stretching the possibilities of the aircraft.
[url= http://www.telegraph.co.uk/technology/9231855/Air-France-Flight-447-Damn-it-were-going-to-crash.html ]A quick read of this will make the series of events on the AF plane clearer[/url]
Lets hope its not a copy and paste job for the Air Asia crash - although it's becoming harder to find occasions when the pilots actions have actually helped matters 🙁
(Hudson river for example)
This is better IMO as it has more of the transcript from the voice recorder.
butcher - Member
They did say on the radio just before that it may have been an updraft produced by the storm, because to climb that fast would really be stretching the possibilities of the aircraft.
Found this, might explain a bit more:
Ever wonder how fast air is rising into the sky during a developing thunderstorm? What about during a Tornado? Here I will try to explain what I know about vertical wind speeds in the centers of natures most violent storms.Here I will start with the basics. Convection is simply the rising of warm air and the sinking of cooler air. To have clouds, there must be rising, warm and moist air (compared to air surrounding the air "parcel") where the moisture condenses at a certain altitude, forming the cloud. This rising air may be a thermal, from the uneven heating of the earth's surface, or forcing / convergence caused by a front, mountain range, or inflow of air into a low pressure system.
Another important thing is that more heat energy is transferred to this air parcel as the water vapor condenses (or freezes). This makes the air parcel warmer and causes it to rise faster. About 540 calories of energy are released as a single gram of water condenses! When each gram freezes, an additional 80 calories is released. The small fair weather cumulus often have updraft speeds of about 5 MPH.
The really impressive updraft speeds occur in developing thunderstorms and especially in supercells. In a general (non-severe) thunderstorm, the development and early-mature cycle is when the updraft is strongest before downdrafts begin to disrupt the storm. Typical speeds range from about 15 to 30 MPH, or roughly 1,200 to 2,500 feet per minute. At this rate, the relatively "weak" storm reaches a height of about 30,000 feet in 15 minutes, and may last only a half hour.
Severe thunderstorms, require much stronger updraft speeds and depend on the type of storm. Multicell lines generally have weaker updrafts than multicell clusters but are arranged in a "curtain". The updraft speeds in a multicell line storm are a bit stronger than the single cell general storm described earlier. Multicell cluster storms often have updraft speeds around 60 MPH in developing components, or about 5,500 feet per minute. This is quite fast, keeping in mind that most general aviation aircraft can only climb up to 3,000 feet per minute (200 Super King Air).
This is also why pilots should NEVER try to "out climb" the top of a developing thunderstorm. The strongest updraft speeds lie with the most intense kind of thunderstorm, the supercell. A supercell is a "continuous cycle" storm, meaning that it has an updraft side and downdraft side at the same time which are separated from each other allowing the storm to last much longer than 30-45 minutes.
The updraft of a supercell also has a broad low and / or mid-level rotation (mesocyclone) which my further boost its speed. Supercell updrafts generally are stronger than 50 MPH, but 70 or 80 MPH is more typical. In the Great Plains of the United States, supercells often produce baseball and grapefruit sized hail (not to mention tornadoes) because of the extreme speeds of the updrafts within. Such updrafts have been known to reach 150 to 175 MPH, or about 12,000 to 15,000 feet per minute!
No aircraft except for military fighter jets with afterburner power could climb at these rates (for example, the F4 Phantom and Lear 35 Jet both have maximum climb rates less than 8,000 feet per minute). This is why a supercell can literally go from "blue sky to tornado" in a "New York minute". At 15,000 feet per minute, an air parcel will go from ground level to 45,000 feet in only 3 minutes!
An experiment was done via special weather balloon to find out how quickly a supercell updraft will carry it. The device was released into the inflow side of an HP supercell in the Great Plains and ingested into the storm. Only 2 and a half minutes later, the balloon was in the anvil of the storm. It rode the high-velocity core of the storm and gave vital information on the structure of the storm and internal dynamics.
Supercell storms are the most dangerous to aviation. Visibility and wind-shear are the most obvious threats at low levels, however, the updraft and mesocyclone is usually strongest at 20,000 feet. A commercial airliner flying though such a storm will most likely have its wings torn off, and this has happened to planes trying to fly through severe thunderstorms.
Another pilots horror story was an L1011 trying to fly through a "hole" in a multicell cluster of severe thunderstorms. Invisible to the pilot, was that baseball sized hail was falling through that "hole" in the storm, and serious damage to the aircraft was sustained (cracked windows, cratered leading edges of wings, and crushed engine nacelles).
The most amazing stories come from several incidents of people who were unfortunate enough to parachute into a thunderstorm. Imagine a 100 MPH updraft, your parachute is descending at 10 MPH ... Do the math, this means you will go back UP at 90 MPH!
Google has an odd sense of humour.
It is advertising Kan Airlines on the right of this page with a photo of an old looking turboprop anda map of where they fly to.
Yes agreed with that - I don't agree though that re-designing the systems /instrument panel would have necessarily saved it though. I personally doubt it would, but that is pure opinion.
But the computer already gets angle of attack information. It just doesn't relay this to the pilots. The screwed up pitots caused the computer to basically give up trying. IMO the software is badly written. In the case of the computer getting erroneous data and knowing it the software should declare this to the pilots and present data they need to make the decisions to fly the plane. They have a fancy cockpit full of screens. Changing what they display is simple.
That said they still should have realised what was going on and I think there was holes in their training.
I just don't thinkbthat the systems are as well thought out as they should be. I provide consultancy on how they make aircraft and my views are the same for the mechanical components. There is a lot of stupid reluctance to introduce things if they don't fit into the bean counters plans or if it will highlight something they have been doing wrong for years but is accepted. Classics are "well we had thought of this but it won't happen" to "hmm that will cost money so we will keep trying to do it our way first even though we called you in as its not worked so far the other times we have tried it"
Better models may help?
http://arstechnica.com/science/2015/01/the-future-of-control-putting-virtual-wind-turbines-inside-real-ones/
As mentioned above, if the radar data supports the statement that the aircraft was climbing at 6000fpm, it's unlikely that the pilot was in complete control of the aircraft. An A320 on an early morning run would most likely be fully fuelled and loaded (maximising sectors whilst minimising turnaround) in such conditions, an A320 at FL320 wouldn't have the lift or thrust to climb to FL380 in less than a minute without something else going on. At those altitudes and loads, I'd say 1000-1500fpm would be just about doable without either of the stall warnings going off.
A320 has a VSW which is largely driven by airspeed and a ASW triggered by AoA. If you trigger both at the same time, you're likely already in complete stall.
With the greatest of respect an awful lot of the comments above are ill informed, inaccurate and typical of how Joe public views pilots and aeroplanes. 1000's of times a day pilots all over the world make good solid decisions and many of those are correctly dealing with situations where things have gone wrong. You don't hear about those much do you? We prefer to just focus on the more newsworthy stories that involve fatalities but these are still extremely rare in the scheme of things.
Until you have been at the controls of an airliner in severe weather, with severe turbulence (so bad you can't even read the instruments), with failing instruments giving conflicting information and the automatics not doing what they are meant to, you really can't imagine what it's like.
When things go wrong they go wrong big style and incredibly quickly. Don't be so quick to judge
If you trigger both at the same time, you're likely already in complete stall.
The cause of the stall is irrelevant to the OP. The question is; how can an aircraft stall at FL320 and make it all the way down to the water (it must have been in freefall for 2 or 3 minutes), without at some point getting it's nose into the airflow? I was under the impression they are designed with a natural tendancy to right themselves...?
I'm not a pilot (clearly) but I do work in load planning, and we go to a lot of effort to make sure the aircraft trims and ballances correctly. Yet this one seems to have lost ballance altogether.
I do have a lot of criticism for Airbus and the general aviation industry for stupidty in design of aircraft systems.
What a stupid and bizarre thing to say.
There is nothing wrong with Aircraft system design. There are mistakes made by humans.
An A320 takes off or lands around the world every 2 seconds. They have produced and sold over 10,000 and not one has been lost due to a failure in an aircraft system.
Duffer - MemberThe cause of the stall is irrelevant to the OP. The question is; how can an aircraft stall at FL320 and make it all the way down to the water (it must have been in freefall for 2 or 3 minutes), without at some point getting it's nose into the airflow? I was under the impression they are designed with a natural tendancy to right themselves...?
On the Air France flight, IIRC one pilot was pulling back on the stick the entire time it was falling.
Hopefully this one is not something as simple as that.
If only there was some sort of logging device in commercial aircraft that would be able to tell us what happened. It would probably need to be analysed by aviation apecialists.
Exactly
Can someone explain the reason for the design decision to make the sticks physically independent? I thought on a Boeing they were linked and as such the Air France crash could not have happened.
I gather the newer designs are physically indipendent, but digitally linked. Where there is a discrepancy, the computer will favour the left-hand seat.
Others will no doubt be able to provide a more detailed answer.
Can someone explain the reason for the design decision to make the sticks physically independent? I thought on a Boeing they were linked and as such the Air France crash could not have happened.
They are independent in case the system is receiving input that the pilot wants to exclude. An example of this would be the other pilot becoming incapacitated, with their body leaning against the sidestick.
The LHS seat can take full control in this case by pushing the Priority Takeover button to eliminate the other pilot's input.
At all other times it takes an aggregated input. Much more safer system to have one input available than linked sticks.
gofasterstripes - MemberCan someone explain the reason for the design decision to make the sticks physically independent?
I would have thought in situations where the sticks are receiving a different input, it would be sensible for the cockpit voice woman would say something along the lines of 'different stick inputs detected'.
There seems to be quite a few people on here with knowledge of aviation systems.
Apart from scenario of a co-pilot who's had a dodgy curry and is slumped on the stick, what 'normal' circumstances are there where you would want/expect differential inputs between the two sticks?
Normally you would have differential inputs between the sticks all the time. i.e. Only the person that is flying the plane is making inputs.
It would probably need to be analysed by [s]aviation apecialists[/s]STW.
FTFY 🙂
STW doesn't need data.