Is this normal for a cruise altitude?

Hello I have a question I am flying on FL400 mach 0,78, Just normal I think
My airspeed is 220 and my groundspeed is 447 so that looks also normal.
Just like an B737 real world.image

But my trottle is standing 85% I am sure that KLM don’t have the trottle 85% so What do I wrong or is this a fault in IF?


Perhaps a heavy tailwind increasing the aircraft’s momentum? Temperature? VS?

If you’ve got your speed set at 0.78 and the wind is increasing the aircraft’s speed, naturally the throttle will want to decrease to avoid exceeding 0.78M.

Temp is -56 in the air

VS 0

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No wind 0 KTS wind here it is socal

Tailwind in KTS + G?

No tail wind groundspeed is 447 KTS

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Why not?
N1 is about 90% while cruising.

Bcoz I think (I think) that almost 90% is to much the use for take off not on cruise attitude (I think)

I don’t think that that KLM has his trottles on 86%

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I found someone that is saying cruise attitude speed Should be M0,75 but now I am flying 210 airspeed almost must use flaps or maybe must use
Here I found

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@Laurens do you maybe know it?

You can count on Laurens for info. If he’s said it’s possible I reckon it is.

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Looks completely normal. Mach .78 to .84 are typical average cruise speeds above FL280. It depends of course on atmospheric conditions and aircraft load. .78 is most common cruise speed for these aircraft. Relatively slow, but better for fuel and engines.


Yes but under the 0,76 M I almost need flaps and I still must use more then 85% of the engines

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Then you are either too high, or overloaded for the altitude.
Make sure spoilers are completely off. Do not use flaps at cruising altitudes and speeds.
Descend to an altitude where you can cruise with %80 throttle with a Mach speed of at least .77


Weight was normal and I taught hé that KLM is cruisend on FL400 I also going to do that

BTW FL400 would usually be flown after an aircraft like this has burned off much of the fuel. The aircraft load will usually be relatively light and they would’ve most likely been slowly climbing as the weight decreases. A fully loaded, freshly fueled 737 isn’t likely to climb to FL400 to cruise right away because it’s too heavy. Again this may depend largely on weather conditions. No single flight is universal to all. Make sense? :)


I’m a little misty here, is he surprised that as much as 80% is required or as little as 80% is required?

Bottom line or rule of thumb is: If you can’t cruise with about %80 throttle at Mach .78 you’re too high for the current aircraft weight or weather conditions.

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