Flap Deployment: AS or GS?

I understand that flaps are deployed at certain speed but my question is are you using the airspeed or ground speed to do so.

I, for example, love flying the 772ER and 772F. Ive been deploying flaps using my airspeed not ground.

235kts - 1*
220kts - 5*
200kts - 15*
185kts - 20*
170kts - 25*
155-160kts - 30*

I know some of you guys are gonna come on here telling me that I have been doing it all wrong but in all honesty, I have found my flights and descents to be very smooth. (my crosswind landings are trash though, ask anyone in TFS)

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It’s always airspeed.

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had to ask, I wasnt sure because I had this brought up to my attention by someone who uses groundspeed instead.

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Yes, GS has nothing to do with it. :) The limitations are based on how much resistance the flaps can handle safely. :)

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Bear in mind they are limits, so the highest speed you could set that amount of flap. Doesn’t mean that you set the flap as soon as you reach that speed. For example the 737-800 (sorry I know I always refer to the 737-800 but it is the aircraft I am most familiar with) has a flap extension limit of flap 1, 2, and 5 below 250kts. This doesn’t mean that as soon as you get to 250 kts you immediately set flap 1, 2, or 5, it just means you could set down to flap 5 and not damage anything.

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Don’t worry Alan air speed is the correct way to go! Anyone who says GS needs to go back to ground school!!

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