Originally Posted by
Linktrained
The example that I had done to me on a Britannia with a new Captain who HAD to go from Flight Idle to Overshoot, MAY have been faster... But it seemed an age. (A Merlin would have been even better.)
Yup, that seems to be the thing with jets. In fact according to my copy of HTBJ, a lot of early problems during the prop-to-jet transition came from pilots who hadn't quite internalised the knowledge that with jets there was a significant increase in lag between a thrust command and that thrust being available compared to the old propliners they were used to.
That behaviour in Direct Law makes sense - it behaves just as any conventional aircraft would in that situation. If you're low and slow, then you have to sacrifice some altitude while the thrust increases to a point at which you can initiate a climb, no?
AF447 is a little different, being a high-altitude stall, and additionally the aircraft had sufficient thrust at the onset of AP disconnect to keep flying. It was the pitch up command that led to the bleeding-off of airspeed - but this wasn't a "maintain altitude" magnitude of pitch-up order, it was of a magnitude much greater.