FlyDubai 737-800 down in Russia
Discussion
I just wonder whether this was a case of 'Somatogravic Illusion' ('Pitch Up Illusion').
The aircraft was IMC (ie in cloud) at night, so there were no visual references (other than the instruments) and carrying out a 'Go Around' (overshoot) - a classic time when this illusion can occur.
Effectively what happens is that, as the aircraft accelerates, the fluid in the inner ear is displaced rearwards causing movement of the otolith. This is interpreted by the brain as a pitching upwards sensation.
This sensation can be so strong as to produce extreme disorientation resulting in a pilot inputting inappropriate control movements (ie pushing forward on the stick). As the aircraft then accelerates further the pitch up illusion continues (and gets worse) so more forward stick movement is made with the obvious conclusion.
The aircraft was IMC (ie in cloud) at night, so there were no visual references (other than the instruments) and carrying out a 'Go Around' (overshoot) - a classic time when this illusion can occur.
Effectively what happens is that, as the aircraft accelerates, the fluid in the inner ear is displaced rearwards causing movement of the otolith. This is interpreted by the brain as a pitching upwards sensation.
This sensation can be so strong as to produce extreme disorientation resulting in a pilot inputting inappropriate control movements (ie pushing forward on the stick). As the aircraft then accelerates further the pitch up illusion continues (and gets worse) so more forward stick movement is made with the obvious conclusion.
Sounds on the money to me, thing is, this isn't the first time a Pilot has caused a crash due to not trusting the instruments, has it ever happened the other way around where the instruments have mis-read and caused a crash?
...because if not you'd think they'd train pilots to ignore their body and follow the instruments no matter what.
...because if not you'd think they'd train pilots to ignore their body and follow the instruments no matter what.
Mansells Tash said:
Sounds on the money to me, thing is, this isn't the first time a Pilot has caused a crash due to not trusting the instruments, has it ever happened the other way around where the instruments have mis-read and caused a crash?
...because if not you'd think they'd train pilots to ignore their body and follow the instruments no matter what.
Sort of yes, Air France 447. Unreliable airspeed indication conspiring with some good old fashioned pilot error....because if not you'd think they'd train pilots to ignore their body and follow the instruments no matter what.
Mansells Tash said:
Sounds on the money to me, thing is, this isn't the first time a Pilot has caused a crash due to not trusting the instruments, has it ever happened the other way around where the instruments have mis-read and caused a crash?
I believe the BMA 737 crash at Kegworth was caused by an instrument that was not as "untrust-worthy" on previous variants being ignored and having some bearing on the crash.Kegworth was the result of misidentifying which engine had failed and the shutting down of the wrong engine.
It was exacerbated by the layout of the engine instruments on that model of 737 being different to earlier models, lack of crew experience on that model, and poor CRM (Crew Rsource Management).
It was exacerbated by the layout of the engine instruments on that model of 737 being different to earlier models, lack of crew experience on that model, and poor CRM (Crew Rsource Management).
Ginetta G15 Girl said:
Kegworth was the result of misidentifying which engine had failed and the shutting down of the wrong engine.
It was exacerbated by the layout of the engine instruments on that model of 737 being different to earlier models, lack of crew experience on that model, and poor CRM (Crew Rsource Management).
I knew it was the wrong engine, just looking at the reasons he thought it was that engine.It was exacerbated by the layout of the engine instruments on that model of 737 being different to earlier models, lack of crew experience on that model, and poor CRM (Crew Rsource Management).
That report isn't easy to decipher and I'm as familiar as you can be with the 737.
The 12 seconds of nose down pitch trim is the ultimate cause; the question is why did it happen?
Obviously, they accident investigators will have the information, but knowing what flight modes were engaged (FMAs) will probably provide most of the answers. 18 degrees of pitch at 1900ft isn't beyond the realms of possibility and so one possible cause of the pitch down could be the flight directors bars commanding an altitude of 3000ft to be captured. The crew had planned and briefed to climb to FL80, but this needs to be manually set in the Mode Control Panel.
The 12 seconds of nose down pitch trim is the ultimate cause; the question is why did it happen?
Obviously, they accident investigators will have the information, but knowing what flight modes were engaged (FMAs) will probably provide most of the answers. 18 degrees of pitch at 1900ft isn't beyond the realms of possibility and so one possible cause of the pitch down could be the flight directors bars commanding an altitude of 3000ft to be captured. The crew had planned and briefed to climb to FL80, but this needs to be manually set in the Mode Control Panel.
Just been out drinking with a 737 and 777 pilot for Etihad. His best guess is a combination of many factors (in no particular order):
1. Flight deck crew exhaustion to the point of drunken state of awareness
2. Low visibility (i.e. flying on instrumentation alone)
3. Cockpit confusion leading to disagreement on aircraft state (see point 1.)
4. Failure to revert from final approach trim
5. Ultimate failure of the controls and therefore no control of the elevators due to the apparent severe opposing forces being exerted on each of the control sticks.
1. Flight deck crew exhaustion to the point of drunken state of awareness
2. Low visibility (i.e. flying on instrumentation alone)
3. Cockpit confusion leading to disagreement on aircraft state (see point 1.)
4. Failure to revert from final approach trim
5. Ultimate failure of the controls and therefore no control of the elevators due to the apparent severe opposing forces being exerted on each of the control sticks.
pushthebutton said:
Age isn't as relevant as you'd think. I'm sure they exist, but I can't recall the last accident investigation that concluded that the cause was the age of the aircraft. Generally, they are at their most unreliable when they are brand new or getting to the end of their service life, but regular, targeted maintenance can overcome the latter. The autothrottle failing is a catch all phrase; it generally means not operating as intended. The Turkish 737-800 incident at Amsterdam could be described as an autothrottle failure, but was caused by a faulty left side radio altimeter input into the autothrottle control software. It was also a new aircraft.
If I had to recall the number of times the autothrottle dropped out on me I'd lose count after running out of fingers and toes. Such issues are relatively common and dealt with as a matter of course but, if they're not, you read about it for years to come.
Chalk Ocean Airways N2969, does that count?If I had to recall the number of times the autothrottle dropped out on me I'd lose count after running out of fingers and toes. Such issues are relatively common and dealt with as a matter of course but, if they're not, you read about it for years to come.
pushthebutton said:
Wow. One has to wonder if one of the reporting or XXXX Pilots listed were involved in this incident.Are the mainstream carriers better? Reason I ask is I do many (12+) longhaul flights on Qantas a year and really don't want to worry when doing so.
robm3 said:
pushthebutton said:
Wow. One has to wonder if one of the reporting or XXXX Pilots listed were involved in this incident.Are the mainstream carriers better? Reason I ask is I do many (12+) longhaul flights on Qantas a year and really don't want to worry when doing so.
pushthebutton said:
Nothing out of the ordinary there. Standard fare for virtually every low-cost airline.Gassing Station | Boats, Planes & Trains | Top of Page | What's New | My Stuff