"An erroneous AOA input can cause some or all of the following indications and effects:"
"IAS DISAGREE alert."
The whole "what to do" is then:
"Initially, higher control forces may be needed to overcome any stabilizer nose down trim already applied. Electric stabilizer trim can be used to neutralize control column pitch forces before moving the STAB TRIM CUTOUT switches to CUTOUT. Manual stabilizer trim can be used before and after the STAB TRIM CUTOUT switches are moved to CUTOUT."
We know now that the pilots performed what was there laconically written, and that even these actions couldn't save the plane.
Which means either:
- Boeing never actually tested how to really handle the situation described then or
- Boeing indeed tested that and knew that IAS DISAGREE procedures would also be followed and which would guarantee to make the plane uncontrollable (for details see here: https://leehamnews.com/2019/04/03/et302-used-the-cut-out-swi... how one pilot recently reconstructed that and made a video about it, which was later withdrawn on the demand of the pilot's company -- note a single pilot here did what Boeing, which is supposed to sell hundreds of billions USD worth of these planes didn't want to do), but bet on "it won't happen soon enough, we can get away with it."
I can't find that anybody can excuse either of these.
The pilots didn't actually do that. They did not use electric stabilizer trim to "neutralize control column pitch forces before moving the STAB TRIM CUTOUT switches to CUTOUT" in fact the trim had been run markedly down by MCAS by the time they switched off the electric trim.
https://www.avm-mag.com/faa-issues-emergency-ad-for-boeing-7...
"An erroneous AOA input can cause some or all of the following indications and effects:"
"IAS DISAGREE alert."
The whole "what to do" is then:
"Initially, higher control forces may be needed to overcome any stabilizer nose down trim already applied. Electric stabilizer trim can be used to neutralize control column pitch forces before moving the STAB TRIM CUTOUT switches to CUTOUT. Manual stabilizer trim can be used before and after the STAB TRIM CUTOUT switches are moved to CUTOUT."
We know now that the pilots performed what was there laconically written, and that even these actions couldn't save the plane.
Which means either:
- Boeing never actually tested how to really handle the situation described then or
- Boeing indeed tested that and knew that IAS DISAGREE procedures would also be followed and which would guarantee to make the plane uncontrollable (for details see here: https://leehamnews.com/2019/04/03/et302-used-the-cut-out-swi... how one pilot recently reconstructed that and made a video about it, which was later withdrawn on the demand of the pilot's company -- note a single pilot here did what Boeing, which is supposed to sell hundreds of billions USD worth of these planes didn't want to do), but bet on "it won't happen soon enough, we can get away with it."
I can't find that anybody can excuse either of these.