Why is ATC given Ground Speed?

Wouldn’t it be easier for ATC to be given airspeed, not ground speed? When ATC gives an aircraft a select speed, they give it in airspeed. How is ATC supposed to know if the airplane is flying at that airspeed, when its shown as ground speed?

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All ATC instruction is given in KIAS (Knots Indicated Airspeed), as this is the only way to enter the speed directly from a pilots perspective. If Approach tells an aircraft not to exceed 320kts, they are saying do not exceed 320kts KIAS, so then the pilot would be sure indicated airspeed does not exceed 320kts.


Is KIAS the same as the airspeed we see (as a pilot)?

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Thanks, @Rotate, @dan

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Woah this is one old topic, before @Henrik was a moderator.

Yes, and this is necroposting


Who was @dan ? Haven’t seen him before on the community

He is also one of the FDS Staff