Posted on 01/20/2015 8:24:32 AM PST by SeekAndFind
An AirAsia plane that crashed into the Java Sea last month with 162 people on board climbed at a faster than normal speed and then stalled, the Indonesian transport minister said Tuesday.
Flight QZ8501 went down on Dec. 28 in stormy weather, during what was supposed to be a short trip from the Indonesian city of Surabaya to Singapore.
Indonesia's meteorological agency has said bad weather may have caused the crash, and investigators are analysing the data from the jet's black boxes before releasing a preliminary report.
Just moments before the plane disappeared off the radar, the pilot had asked to climb to avoid the storm. He was not immediately granted permission because of heavy air traffic.
"In the final minutes, the plane climbed at a speed which was beyond normal," Transport Minister Ignasius Jonan told reporters, citing radar data.
"The plane suddenly went up at a speed above the normal limit that it was able to climb to. Then it stalled."
(Excerpt) Read more at businessinsider.com ...
When I wrote, I was thinking of the parallels between wind action in a thunderstorm, and flying in mountains in that a pilot can momentarily get confused as to the correct action to take in a temporary updraft.
Yes, your suggestion was/is a possibility, but it might have been a stall produced rather than just a dive. But the FCS computer might have been the problem (like the Paris airshow crash, post 12) rather than the pilot.
I must be getting cynical in my old age. My first thought upon reading the headline was “whitewash”. Or “hogwash”, maybe. I can’t get myself to believe that the crash was the result of weather or system malfunction. We can spend all day debating and theorizing and talking about all the possibilities, but we will never get anywhere near the truth.
“Airbus pitot tube icing?”
I said this on a thread when it first happened and got flamed. I think Air France ha similar flight data. If it ain’t Boeing I’m not going.
IIRC there were three crew members. The Senior captain was sleeping after an all-nighter with his GF in Rio, leaving two juniors as PF and PNF. He left the cabin shortly before they were due to hit some dicey weather. He returned in time, but did not recognize what was going on quickly enough (or at all).
A crash is when you run out of altitude, airspeed and ideas, all at the same time.
I made no claim the pilot was manually controlling the airplane. Regardless, if the crash was caused by faulty instrumentation, systems or pilot input, he is ultimately in charge of controlling or correctly interpreting these things. Failure to do so and losing your plane defines pilot error.
Not so. If the primary cause is, say, a control cable to the tailplane snapping (or a critical instrument failure in IMC), that is not listed as pilot error, but a systems problem. In the Airbus case, the ‘control cable’ is an FCS computer and an electrical wire.
It is conceivable that if a plane is on the edge of it's performance envelope or encountering icing conditions a significant change in altitude could induce controlability issues.
Airbus = nasty. I would rather walk than ride in one of those kludges.
No modern fly-by-wire design has a single point failure mechanism in any aspect of flight control systems.
The FCS controllers are typically triple redundant and the control system actuators also have redundancy.
In addition reliability testing is done to the nth degree on all electro-mechanical systems that actuate flight control surfaces.
Aircraft break-up, serious design flaws, serious software errors or pilot error are realistically the only things that could compromise the systems.
Entering weather, even thunderstorms would likely not be the cause of the crash, just a contributing factor. If the pilot lost his plane solely due to the thunderstorm, then, again it is pilot error because he made a bad decision to penetrate the storm.
My bet on the outcome of this investigation? The finding will be pilot error.
I should add that you are probably right when you say that it will probably be called pilot error, anyway. The airline manufacturers such as Airbus bring intense pressure to bear on not blaming their product. The $$$ involved in that blame issue are enormous. IIRC the Brazil crash was blamed on pilot error, even though the pitot-head design was faulty and screwed up the air data input to the rest of the FCS.
Do aircraft still use some modern version of the old Ryan Stormscope? Paul Ryan (not the Congressman) is one of our alums:
You trim for airspeed, not altitude. Power controls altitude.
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