? For ATC; varying speed under IFR flight plan

[JOhnH]

I recently had a couple of cylinders overhauled. Part of the break-in process is to vary the power between 65% AND 75% every 15 minutes. If I am under an IFR flight plan will it annoy anyone or cause any issues if I keep varying my speed up and down for a while?

 

[luvflyin]

I recently had a couple of cylinders overhauled. Part of the break-in process is to vary the power between 65% AND 75% every 15 minutes. If I am under an IFR flight plan will it annoy anyone or cause any issues if I keep varying my speed up and down for a while?

Maybe. How many knots we talkin about?

 

[Brad Z]

I recently had a couple of cylinders overhauled. Part of the break-in process is to vary the power between 65% AND 75% every 15 minutes. If I am under an IFR flight plan will it annoy anyone or cause any issues if I keep varying my speed up and down for a while?

The controller will never notice.

 

[Radar Contact]

I recently had a couple of cylinders overhauled. Part of the break-in process is to vary the power between 65% AND 75% every 15 minutes. If I am under an IFR flight plan will it annoy anyone or cause any issues if I keep varying my speed up and down for a while?

ATC won’t notice or care about 10% of any plane that has cylinders.

 

[Larry in TN]

The official answer is 5% or 10 knots, whichever is greater, per AIM 5-3-3. 5% doesn't come into play until your TAS is over 200 knots.

The issues would be when you're sequenced behind, or in front of, other traffic on the same route. That's more of an issue for jets or outside of radar service.

 

[gacoon]

How will they know its you or a wind change, especially if your speed doesnt change that much,

 

[luvflyin]

How will they know its you or a wind change, especially if your speed doesnt change that much,

because another plane in the same wind starts overtaking or being overtaken by you. But like you said if the speed difference is small it ain’t gonna be a big deal. Plenty of time for the controller to respond to it.

 

[N1120A]

I once had a controller tell me to climb and maintain 15000. I said "unable" (no O2 and that's not a good altitude for a NA piston anyway) and was kinda shocked. I'd filed for and been cleared to 11000 by tower. Dead air. "Oh, that's your speed, maintain 11000."

I really doubt they care, unless there is someone else bearing down on you or that you are bearing down on.

 

[JOhnH]

Thanks everyone. We are only talking about maybe a 10 kt diff (From 160 to 170).

 

[frfly172]

As long as they don’t have to adjust other aircraft because of your speeds ,there shouldn’t be a problem.

 

[Larry in TN]

I really doubt they care, unless there is someone else bearing down on you or that you are bearing down on.

Right. They don't care, until they do. No way for a pilot to know when they will, or will not, care.

Thanks everyone. We are only talking about maybe a 10 kt diff (From 160 to 170).

Well, A 10 knot change is the trigger, for TAS up to 200 knots, for a report under AIM 5-3-3, so shoot for 9.9 knot changes and you don't have to worry about it.

 

[Busflyer]

No

 

[Timbeck2]

Nope

 

[4CornerFlyer]

I think this would be more of an issue in a non-radar environment, meaning few places in the continental US. If you're on radar, the controller knows you speed--at least the speed that matters. That being said, the AIM does specify what you are supposed to do.
Jon

 

[AeroLudite]

File for the lower speed. No one will notice or care. I’ve only been told to maintain maximum forward speed! Never slow down except by tower controller at Orlando Exec. I was in a Turbo Saratoga, kept calling me a Cherokee . Lots of Skyhawks in the pattern...