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Cruise performance same power setting decreased TAS

Asked by: 2688 views Aerodynamics, Aircraft Systems, Commercial Pilot, Flight Instructor, General Aviation, Private Pilot, Student Pilot

OK, so when look at PIM, cruise performance chart, as the altitude increases, airspeed decreases. Why is that?

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1 Answers



  1. humble and fly on Apr 20, 2016

    It depends. If your aircraft is turbine or turbo/supercharged aircraft, Your cruise speed will go up with same power setting because engine can produce rated horse power until critical altitude.

    IF you have Normally aspirated engine, Rated horsepower will decrease as altitude increase. So even if your engine rotates at maximum RPM, Horsepower is less.

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