# Cruising speeds

Hello,
I want an advice from you. When I want to cruise at M0.78 for example how do you know what IAS is that after passing 10000ft so it is M0.78 above FL280? I always have problems with this, do you use some page for this or how do you know that?

Thanks a lot.

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290 is around 0.78 i think

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I usually memorize the speeds. Most of the time M 0.78 is 290-295 KIAS

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Thanks, but is there any page or post on the IFC with these speeds for all planes? There are lists with the mach speed, but I think it would be useful to have a list with these speeds above 10000ft.

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FPLoIF usually tells you the cruise profile for each aircraft

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Just clarifying, youâ€™re asking for the exact IAS Mach speed? If so, there isnâ€™t one because of your current position and speed relative to Mach, which is a function of the environment youâ€™re passing through. The difference isnâ€™t much, 1-3 knots for most short-medium hauls.

The higher you go, the more important it is to know what speed youâ€™re at in relation to Mach. At 10000, commercial aircraft wonâ€™t be anywhere close, so an IAS is fine. Above FL280, youâ€™re in an environment where Mach effects can start to cause issues to your plane, so the speed is given in relation to Mach and no longer in knots.

If youâ€™re asking for plane cruise speeds, theyâ€™re listed around here and on other pages like SimBrief for different aircraft.

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You can follow it by display screen. It shows all the mach, ias and gs.

Hi!

Check this topic below to help you regarding speeds and fuel burns :)

293kts is M0.78
300kts is M0.80
314kts is M0.84

Those are one ones that I remember.

If you set those then as you pass 28,000ft youâ€™ll be at the Mach you want

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Thanks, I didnt know that.

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Go to 320 for the 787 to cruise at M 0.85

Doesnâ€™t for me. How do you get that?

It shows up like this

The A320 familyâ€™s cruise profile. 250/290/78 is more accurate in IF

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This is just one chart, there are other variables, but you donâ€™t really need to know the exact IAS above FL280. (Chart is for the B738):

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