4 ms·

Unflyable or unstable isn't nearly the same thing as uncertifiable. People have flown a whole lot of time in uncertifiable aircraft (see the whole experimental

Unflyable or unstable isn't nearly the same thing as uncertifiable. People have flown a whole lot of time in uncertifiable aircraft (see the whole experimental aircraft sector) but transport category aircraft are supposed to exhibit as full proof as possible behaviour. I bet you it flies again with MCAS. I'll also bet it flies with barely a few hours of conversion training and that there aren't any accidents directly related to the updated MCAS system.

lutorm 7y ago
This isn't true though, it seems perfectly possible to certificate transport-category airplanes with sketchy stall characteristics, since T-tail planes can end up in unrecoverable situations by blanketing the tail in a stall. Twin-engine planes also are not required to be recoverable from an engine failure at speeds below Vmc. I don't know what the certification requirements are, but it seems they rely on being able to guarantee that you never get below a certain speed since in multi-engine airplanes there's always a low power/high thrust regime that's potentially uncontrollable.
- salawat 7y ago
  While the FAA has allowed it, not all aircraft have been certified to fly in all airspace without safety systems to prevent stalls. Give the D. P. Davies Interview, recorded by the Royal Aeronautics Society a listen, and you'll learn how the 727 was not allowed to be certified in the U.K. without a stick pusher equipped. I think it's this one. https://www.aerosociety.com/news/audio-the-d-p-davies-interview-on-testing-the-comets-boeing-707-britannia-brabazon/ https://www.aerosociety.com/news/audio-the-d-p-davies-interv... If not that one then this one. https://www.aerosociety.com/news/audio-the-d-p-davies-interview-on-the-boeing-747-the-trident-vc10-one-eleven-the-boeing-727/ https://www.aerosociety.com/news/audio-the-d-p-davies-interv... Edit: 2nd one I think is the one I'm remembering. Pumping the first one, because...well, it's just damn interesting.

lutorm 7y ago

This isn't true though, it seems perfectly possible to certificate transport-category airplanes with sketchy stall characteristics, since T-tail planes can end up in unrecoverable situations by blanketing the tail in a stall. Twin-engine planes also are not required to be recoverable from an engine failure at speeds below Vmc. I don't know what the certification requirements are, but it seems they rely on being able to guarantee that you never get below a certain speed since in multi-engine airplanes there's always a low power/high thrust regime that's potentially uncontrollable.

salawat 7y ago
While the FAA has allowed it, not all aircraft have been certified to fly in all airspace without safety systems to prevent stalls. Give the D. P. Davies Interview, recorded by the Royal Aeronautics Society a listen, and you'll learn how the 727 was not allowed to be certified in the U.K. without a stick pusher equipped. I think it's this one. https://www.aerosociety.com/news/audio-the-d-p-davies-interview-on-testing-the-comets-boeing-707-britannia-brabazon/ https://www.aerosociety.com/news/audio-the-d-p-davies-interv... If not that one then this one. https://www.aerosociety.com/news/audio-the-d-p-davies-interview-on-the-boeing-747-the-trident-vc10-one-eleven-the-boeing-727/ https://www.aerosociety.com/news/audio-the-d-p-davies-interv... Edit: 2nd one I think is the one I'm remembering. Pumping the first one, because...well, it's just damn interesting.