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Engine power required for taxi

gecko

gecko

Charter Member
One of the worst things about handling CFS3 aircraft on the ground is the ridiculous amount of power required to get them rolling for taxi. You'd think the wheels had sunken into eight inches of mud. I've been playing around lately with the early Spitfire's propeller, trying to get a working two pitch de Havilland prop instead of the constant speed model that they all have right now (promising results so far) and started messing with the low_speed_theory_limit value in the aircraft.cfg. This seems to change the effectiveness of the propeller at low airspeeds (what a thought!). Results so far seem to be that a value of about 8 produces reasonable results with no adverse effects that I have seen so far (almost all the aircraft seem to have that value set at 80). So if you're interested, try out some different values and enjoy a better experience on the ground. As I am doing my testing with a highly modified prop, 8 may not be the ideal value for other aircraft, but it's probably a good place to start.
 
To break loose from a standstill where the shock struts are compressed requires about 80%, which on this aircraft amounts to 1,300 RPM and 29 inhg MAP, so that's still pretty high. If you have come to a stop gently and the struts are not compressed it's about 30%, or about 880 RPM and 14 inhg MAP. And with those settings, a slow but steady 8 mph taxi can be achieved. I'm not sure if 30% throttle is reasonable for that, but nobody in the real world measures piston engine power settings by percent except for cruise anyway, and even then its % BHP and not % throttle. 880 RPM and 14 inhg however, is quite reasonable. This compared to needing 3,000 RPM and 20+ inhg MAP to sustain a taxi before.
 
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