ATC speed commands in KIAS or GS

Lately I have been searching for a topic about this, but as I haven’t found one, I decided to create one.

Sometimes when I receive an ATC command for speed, (such as: do not fly faster than 180kts), I never know if that command is for KIAS or GS. Could someone please confirm if ATC speed commands are in KIAS or GS?

Thank you and happy flights✈️

Actually it is KIAS (airspeed)

The controller sees ground speed so the controller needs to know what speed is appropriate.

2 Likes

Thank you! For example, if a controller says: maintain 180kts, would it be okay to put 180 in the autopilot?

1 Like

Tip -

Greater - Higher than the speed given
Maintain - Slow Down to that exact Speed
Below - Slower than the given speed

Hope that helps

1 Like

Yes. If the controller says to maintain 180 knots, you would put 180 in autopilot.

2 Likes

Thank you! That is what I have always been doing, but a few days back I already was at the speed requested by ATC and he sent again that message to maintain that same speed, making me think if that was GS. I guess he got confused.

Regards,
Ignacio

2 Likes

Thank you!

No Problem

1 Like

If the radar controller says „do not exceed 180kts“ on base you shouldn‘t fly less than 180kts. Aircrafts should fly 180kts on base (in general) but the controller says do not exceed because you can slow down after the intercept. If he‘d say „reduce to 180kts“ he‘d have to say „speed at your discretion“ after that, otherwise you‘d have to continue flying 180kts.

1 Like

Usually if you get the same command it means you are not slowing down quick enough. Check your spacing with planes around you.

1 Like

This topic was automatically closed 90 days after the last reply. New replies are no longer allowed.