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The Other Recent Deadly Boeing Crash No One Is Talking About (nymag.com)
New York magazine's Intelligencer remembers last month's crash of a Boeing 767 carrying cargo for Amazon and the U.S. Postal Service -- and shares a new theory that its cause wasn't a suicidal pilot or an autopilot malfunction:
In online pilot discussion forums, a third idea has been gaining adherents: that the pilots succumbed to a phenomenon called somatogravic illusion, in which lateral acceleration due to engine thrust creates the sensation that one is tipping backward in one's seat. The effect is particularly strong when a plane is lightly loaded, as it would be at the end of a long flight when the fuel tanks are mostly empty, and in conditions of poor visibility, as Atlas Air 3591 was as it worked its way through bands of bad weather. The idea is that perhaps one of the pilots accidentally or in response to wind shear set the engines to full power, and then believed that the plane had become dangerously nose-high and so pushed forward on the controls. This would cause a low-g sensation that might have been so disorienting that by the time the plane came barreling out of the bottom of the clouds there wasn't enough time to pull out of the dive.
It has been speculated that this might have been the cause of another bizarre and officially unsolved accident from three years ago: Flydubai Flight 981, which crashed 2016 in Rostov-on-Don, Russia.... While it's still too early to draw any kind of conclusions about Atlas Air 3591, the possibility exists that a firm conclusion will never be drawn -- and if it is, the cause could turn out not to be a design flaw or software malfunction that can be rectified, but a basic shortcoming in human perception and psychology that cannot be fixed as long as humans are entrusted with the control of airplanes.
It has been speculated that this might have been the cause of another bizarre and officially unsolved accident from three years ago: Flydubai Flight 981, which crashed 2016 in Rostov-on-Don, Russia.... While it's still too early to draw any kind of conclusions about Atlas Air 3591, the possibility exists that a firm conclusion will never be drawn -- and if it is, the cause could turn out not to be a design flaw or software malfunction that can be rectified, but a basic shortcoming in human perception and psychology that cannot be fixed as long as humans are entrusted with the control of airplanes.
Barometric altitude is much more accurate than GPS altitude.
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Yes, commercial pilots are taught to "fly their instruments". General aviation pilots may enjoy more "seat-of-the-pants" flying, but even they are taught to trust instruments over human perceptions, which are easily fooled, as even simple demos will show.
I used to work for an aircraft instrument maker, and our user interfaces, everything the pilot interacts with, got more care and attention than the rest of the instrument. Of course we had to display nothing but totally accurate data, and do so promptly, but we also had to do so in ways that were obvious and clear, so the pilot can take in the most important information with a quick glance.
The pilot's standard "scan" is perhaps the most-trained skill. To look at everything on the instrument panels and outside the windows often enough to not miss anything, yet slow enough to take in all vital information.
When things get hectic, the pilot still does this scan, interrupting it as needed to deal with situations, but still doing it. Because, as the saying goes, "trouble often comes in threes": Stopping everything to handle an initial situation may mask what's really going on, and lead to a cascade of failures.
With ever more data being aimed at the pilot, there is a distinct risk of information overload, especially when tired, or during tense but otherwise normal situations, such as take-off, landing, or flying through turbulence. This overload often encourages the pilot to rely more on signals from the body, which need less conscious processing, rather than focus on all that data.
Here, again, is where commercial pilots receive extra training, but perhaps not often enough. This is one of the factors that keep commercial pilot mandatory retirement ages so low: The risk of overload increases with age, even when all other factors match those of a younger person.
Plus, staying in peak training for decades is fatiguing, and relatively few can do so "naturally". Which is one of the reasons we're running out of commercial aircraft pilots.
It may seem counter-intuitive, but this overload risk is often handled by adding more automation, more automatic systems to "help" the pilot. So much so that actually manually "driving" a commercial aircraft, with hands on the controls, is an increasingly rare part of a normal flight.
Our instruments also tried to take pilot fatigue into account, saving our brightest and loudest alarms only for the most desperate situations, to punch-through that overload to help ensure prompt and correct reactions.
One product I worked on was a TAWS (Terrain Awareness and Warning System) instrument, which basically stayed quiet unless there was a risk of the pilot flying into the ground, to help prevent "CFIT" accidents (Controlled Flight Into the Ground). It has special modes for take-off and landing, though our instrument was designed to actually *avoid* making the pilot depend on it's display: Useful for information as part of the scan, but not to be used to navigate the aircraft. Our main function was to provide visual and audible alerts only when needed.
I believe 100% of US commercial aircraft (and perhaps now even biz-jets) are required to have TAWS on-board and active. Any TAWS-equipped plane approaching the ground outside of an approved approach path for a know airport will give the pilot "Terrain ahead. Pull up! Pull up!" alerts until the hazard no longer exists.
Unfortunately, if a stall is also immanent, the pilot will simultaneously receive an alert to push the nose down. And increase power. And other things as well. An overload of alerts, which a skilled and calm pilot will respond to with the most correct action. But which can overload a stressed or tired pilot, or one with the beginnings of a cold or flu.
The thing is, every alert can be silenced, to reduce the confusion and distractions. But an overloaded pilot can forget even this simple aid to keeping full awareness and control.
This is a big part of why pilots are so often blamed for crashes:
Except a 737 is not a fly by wire airplane with envelope protection.
"It's such a fine line between stupid and clever" -- David St. Hubbins, Spinal Tap
Don't forget the fact that during the 1990s Boeing blamed several crashes of the 737 on pilots, when mounting evidence showed that the 737 had a rudder control issue which caused hard over or rudder reversal events in certain circumstances, such as on approach to landing.