Originally Posted by Astro14
Originally Posted by ZeeOSix
Originally Posted by Astro14
Originally Posted by john_pifer
https://www.ntsb.gov/investigations...CpOsQnij-bBxcql4Ds9u-DuhETTZduBQM7lLY
Thanks - more information, but still too early to tell anything.
I can't answer the question of "was this yoke input from pilot or autopilot?".
Not enough is yet known.
I would think part of the black box data is recording if autopilot is turned on or off. Even if the plane is in autopilot, the controls can be manipulated real time by the pilot. If the controls were done by a human then it leads the investigation down a different path.
It would lead them down a different path.
To date, nothing leads to deliberate crash.
And nothing rules it out, either.
If the NTSB knows, or suspects, they're not sharing.
Not yet.
A split yoke, ala EgyptAir 990, would be extraordinarily revealing...
Astro -
You mention a "split yoke" condition. In the Wiki article for EgyptAir 990, it's mentioned that, in the 767, one elevator up and one down can happen from having at least 50 lbs of differential force applied to each control column. In other words, one pilot was attempting to dive, and the other, to climb, and each was pulling or pushing on his respective column with quite a bit of force.
This brings up a question: The Embraer airliners have a roll control disconnect, as well as a pitch control disconnect, allowing independent operation of the control yoke or control column in case one side of either gets jammed.
The disconnect discs are mounted on the aileron torque tube and the elevator torque tube, underneath the floor, and allow for the pilot and co-pilot control column or yoke to operate in sync, unless one of the disconnect handles on the console is pulled, in which case roll or pitch control is possible by whichever side is not jammed.
I'm sure the Boeing and Airbus aircraft have similar systems.
I've never thought about this before, but your comment on "split yoke condition" got me wondering. What would happen if, during a flight, neither the column nor the yoke was jammed, but the disconnect handles were pulled? Who would have roll and pitch control? The pilot or the co-pilot? Once disconnected, the disconnect discs must be re-connected on the ground. There would be no way to reconnect them in flight.
I've disconnected and removed these discs many times in order to disassemble, lubricate, test them on the bench and re-install, but it's never occurred to me to check flight control operation when they're out.
(Well, the removal procedure calls for installation of rig pins in the control column or control yoke torque tubes in order to prevent any relative movement while the disconnect discs are out, so, by following the manual, we would not be able to perform such a test.)