PPRuNe Forums - View Single Post - Vref + X and Vtgt Question. DH8 pilots anyone?
Old 3rd Nov 2016, 00:48
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Intrance
 
Join Date: Sep 2012
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On my type it's Vref + half of gust, up to Vref+10, no other correction. I am pretty sure this is intended to maintain that 30% margin to stall and to help in keeping the approach stabilized.

Most stabilized criteria (that I have known) include speed not to be less than Vref, adding a bit of margin will help in that. If you would aim to fly Vref in gusty conditions you would quite likely see the speed drop below Vref multiple times and would need to take action by adding thrust or pitching down, both increasing the risk of destabilizing the approach.

I'm not sure why you would add any correction in no crosswind conditions though, perhaps just operator related? Maybe also to reduce the chance at non-stabilized approaches by dropping below Vref?
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