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Flight Model modification for Jane’s WWII Fighters
by Joe Hong

The flight simulation engine appears to have hard-coded the stall behavior. There are practically no spins and there is automatic recovery associated with stalls. In addition, the original flight engine also appeared to limit accelerated stalls. There is a solution for accelerated stalls, but there is none for better stall/spin behavior.

The table CM contains the coefficients for Pitching Moments, and scaling up its values allows the aircraft to exceed the critical stall angle more easily than the original model. The side effect of the modification is to increase the pitch rate of the aircraft, obviously something desirable in any aircraft, but perhaps not very realistic. This trade-off for getting accelerated stalls seems to be worth it, though.

As in the CL/CD modification, a scale factor can be applied uniformly to the values of the pitching moments. This scale factor produces different effects for different aircraft, so some experimentation needs to be done to determine the correct value for each.

There are many other characteristics encoded in the FLT files, but we need to skip those in this short feature. The WWII Fighters message boards in Combatsim and Judge’s own website are excellent forums to focus on individual parameters. This short piece should be enough to get the flight model experts to correct many aspects of the aircraft behaviors, and also give enough understanding to the programming experts to create short utilities.

Click to join a discussion about this article.

References:
D. A. Lednicer and I. J. Gilchrist. Computational Aerodynamic Analysis Methods Applied to the P-51 Mustang. AIAA 9th Applied Aerodynamics Conference. Maryland: Sept 1991.

R. von Mises. Theory of Flight. Dover Publications, NY: 1959.

J. M. Rolf (Ed.) Flight Simulation (Cambridge Aerospace Series). Cambridge University Press: 1988.

 

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