Air Asia Indonesia Lost Contact from Surabaya to Singapore

[snowfalcon2]

Zorin and HarryMann

Agree, very interesting. I did an energy management exercise and plugged in some numbers. They suggest that to bleed off the excess kinetic energy caused by a 50-knot airspeed increase due to the jetstream, the plane needs to climb approx 2000 feet. This corresponds well to the FL370-390 reported by Zorin.

But now if there is even a slight overshoot, speed will decay below the
original speed and at that altitude the stall margin is very small. And with a 6000 fpm climb rate the climb took just 20 seconds, so leveling off needs to be both quick and very precise.

One wonders if a safer strategy for bleeding off excess speed in that situation could be to use the speedbrakes and/or power setting?

Then in the case of QZ8501, that might not have been an intuitive action given that they actually wanted to climb above the weather. Maybe they found themselves in an unexpected but welcome climb, and then just did not realise how quickly they would have needed to level off in order to maintain flying speed.

The FDR data will surely be very interesting.