Originally Posted by
Haroon
........What is the reason of delaying the slats extension so much. Isn't earlier the better? Is it to avoid its pitch up side effect or something else? Thanks.
The primary objective is to immediately reduce the AoA to get out of the stall, which one should do instinctively by immediately pitching down. Your question almost implies that it would be acceptable to hold the AoA and just wait for the the slats to deploy, ("Flap 1" is Slats only when airborne of course). But no: pitch down must be the instant response.
As soon as you have pitched down, you need to remedy why you stalled - you will have been flying too slowly for the wing, so increase thrust to increase speed. Only then, after you have unstalled and have started increasing your speed, you can get some flap(slat) out to give yourself increased stall margin while you get sorted out.
The reason for increasing speed before getting slats out is to arrest any speed decay, which is probably what led to the stall in the first place. If you put slats out first it will increase drag, reduce speed further and confound the problem. So slats are the last consideration, only after you have sorted the speed out.
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