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Old 28th January 2024 | 12:25
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vilas
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From: Wanderlust
Originally Posted by 7600pilot
How is it better to put gear down at 200kts rather than after flaps 3 in the case of G+B hydraulic failure?, because how I see it is putting gear down after flaps 3 we will go into direct law after being trimmed by the THS, whereas configuring after 200kts with gear down means we will have to manually trim the aircraft each time for each flap.
In B+G elevator trim is available so trimming in direct law is not an issue unlike G+Y where stab is frozen at last position and you want elevators at Vapp. So you get to Vapp then put gear down. Here there's different problem.
Lowering gear creates lot of drag. With B+G only half elevator is available so it has to move double the amount to create required g. Also elevator movement is restricted to prevent damage from hitting stops. Higher speed creates more aerodynamic force makes half elevator more effective. Lower speed requires large stick movement in pitch which triggers stall warning.

Last edited by vilas; 29th January 2024 at 06:56.
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