Thread: Stalls
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Old 09-24-2007, 05:32 PM
  #3  
Cubdriver
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Joined APC: May 2006
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VS0 and VS1 are airspeeds where the angle of attack is expected to reach the critical maximum for a particular set of inputs, and they are by no means absolute numbers. The angle of attack is the absolute criterion for stall, and the corresponding airspeed will vary according to a bunch of factors (if you can think of any pls. add), things like cg location, weight load, trim tab setting, gust and load factors, boundary layer fences, vortex vanes, leading edge extensions, and even dirt buildup. They are merely predictions based on typical inputs, they are not absolute airspeeds for stall. Many of the variables are covered in the FAA Airplane Flying Handbook and are included in Certified Flight Instructor programs.

Be that as it may, stall speeds are predictable enough to allow performance computations for landing distances, manuever limitations, and structural limitations to a fairly high degree of accuracy. This is why it is a good idea for a pilot flying a new airframe to take it out for some stalls first, to see what the actual indicated stall airspeeds will be dirty and clean under 1G conditions. A lot of times new pilots struggle with short field work mainly because they have no real idea where the stall is. Familarity with the stall behavior of an airplane helps one implement lower approach speeds while maintaining a 2-3 knot margin for error. Bear in mind stall speeds at altitude are somewhat higher than in ground effect, due to the additional lift available from the low-drag airflow as the airplane nears the ground.

Mike- I am a fan of Barry as well, I like his articles on flight training.

-Cub

Last edited by Cubdriver; 09-24-2007 at 05:51 PM.
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