Stall Recovery vs Tail/Fuselage design

Discussion in 'Aircraft Design / Aerodynamics / New Technology' started by stankap, Feb 6, 2012.

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  1. Jul 29, 2012 #61

    clanon

    clanon

    clanon

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    Not a hijacker here but...

    Related to this :

    Does ventral fins help on this cases ?

     
  2. Jul 30, 2012 #62

    bmcj

    bmcj

    bmcj

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    A ventral fin can help if the design experiences heavy blanketing of the airflow over the fin and rudder.
     
  3. Jul 30, 2012 #63

    orion

    orion

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    Ventral fins, like many other add-ons to established, production aircraft, are usually fixes for what was either a poorly conceived design in the first place or one where the organization wishes to expand the aircraft's capabilities or safety features. Depending on layout and configuration, ventral fins are generally used to aid deep stall recovery by providing assistance to the horizontal tail in generating a positive vertical force. The aid may be required either due to an initially unforeseen condition where the aircraft experiences an excessive amount of blanketing of the horizontal surface, or one where an undersized surface was used.
     
  4. Jul 30, 2012 #64

    bmcj

    bmcj

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    Sorry... meant to say blanketing of the elevator (by the wing in a deep stall). These are the fins you see on the bottom that are not vertical, but jut out on both sides of the tailcone (most often at an angle that is not vertical, nor horizontal.

    A vertical ventral fin can be added to the tail to enhance yaw stability (same effect as enlarging the fin, but it can have a beneficial yawing effect from the prop's spiral slipstream). It may also affect spin recovery if the rudder is subject to heavy blanketing of the airflow by the horizontal tail surfaces.
     

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