FGproperties/Systems/static

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The static system measures the static pressure. So all influences of airspeed are eliminated. In real life this is however not always easy. Effects from angle of attack, side-slip, flap defection, gear extension, engine power setting and airspeed are present and for the aircraft designer it is not always easy to find a good position for the static port.

Usually the number of static systems are equal to the number of pitot systems.

In Flightgear there are 3 types of static systems modeled.

  • Type 0 (default): the perfect sensor. No measurement failures.
  • Type 1: Dual static ports on the fuselage sides. Side-slip angle influence only.
  • Type 2: Static port on the pitot tube. Both angle of attack and side-slip influence.

If you want to use type 1 or 2:

  <static>
    <name>static</name>
    <number>0</number>
    <tau>0.1</tau>
    <type>1</type>
    <error-factor>0.5</error-factor>
  </static>

The output property /systems/static[n]/pressure-inhg is filtered. Therefore, if you want to see the effect of the measurement failure, "tau" should be 0.1 or smaller. The "error-factor" should be between 0.2 and 0.7. Setting it to 0 equals a "perfect sensor". A setting of 1 means the whole (projected on static port face) impact pressure is applied. This is not realistic as usually there are more than one static pick-up points and so the pressure increase gets "flattened".