757 barber poles close to Mmo

The barber poles for the 757 is set at .87, which is only M.01 above Mmo. Doesn’t this open the door for autopilot inaccuracy to cause violations when the pilot is AFK with speed set at .86?

Why would someone cruise that fast? Because a fuel quirk makes .85 more efficient than .80, and it’s likely that some people will use the 757 as a substitute for another aircraft to do a flight at the limit of its range in IF.

The max speed should be the same as the max speed, so it being slightly over is giving it room.

Not an issue though, you should be cruising at .77-.80 anyway.

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