> I dont think anyone has ever been able to figure out why the co-pilot never thought to stop pulling back.
Under the normal fly-by-wire control law, constant back stick wouldn't stall the aircraft. The computers would stop pitching the aircraft up before it reached the stall angle of attack. But, the system had dropped to Alternate law which is a reversionary measure, in this case caused by the pitot system failing.
Under Alternate law, high angle of attack protection is lost and you can pitch up into a stall.
That said, in the AF447 case, the suspicion is that the F/O never even appreciated they were in a stall, irrespective of Alternate law being active.
It's still a mystery why they couldn't comprehend that they were in a stall though. The captain did the math when the co-pilot told him he'd be pulling back the whole time: descending rapidly plus nose up = they were in a stall. He recognized this instantly.
The only explanation is that sometimes the brain just goes haywire during incredibly intense moments. Like pedal misapplications in cars, when people frantically try to brake but jam the accelerator instead, it never seeming to click in their heads that they're speeding up, ie pressing the wrong pedal.
Under the normal fly-by-wire control law, constant back stick wouldn't stall the aircraft. The computers would stop pitching the aircraft up before it reached the stall angle of attack. But, the system had dropped to Alternate law which is a reversionary measure, in this case caused by the pitot system failing. Under Alternate law, high angle of attack protection is lost and you can pitch up into a stall.
That said, in the AF447 case, the suspicion is that the F/O never even appreciated they were in a stall, irrespective of Alternate law being active.