Takeoff

From Bondline

Factors Influencing Ground Roll

For propeller-driven aircraft, takeoff distance has been shown to be nearly proportional to wing loading (aircraft weight divided by wing area) and inversely proportional to the density ratio (actual density divided by sea level density), power-to-weight ratio, and the maximum takeoff lift coefficient.

Effect of the High Compression STC, PowerFlow Exhaust, and Sensenich Propeller

As stated in Basic Engine and Propeller Performance, the improvement in thrust power from the High Compression STC at speeds consistent with the takeoff roll is about 10%. Since takeoff distance is inversely proportional to power, takeoff distance will be reduced by about 10%. To determine the effect of exhaust and propeller improvements, those increments would have to be added to the engine curves as discussed in Basic Engine and Propeller Performance and new RPM equilibrium points found. But like the High Compression STC, the result is more thrust power than the increase in brake power would indicate.

Use of Partial Flaps For Takeoff

Discussion about the use of partial flaps for takeoff can be found in Normal Procedures. While some claim that takeoff performance improves, measured takeoff distance performance did not seem to improve. There is definitely a pitch attitude change that may feel more comfortable for some leading them to claim better performance, and the use of flaps may improve angle-of-climb performance tricking the eye into thinking rate-of-climb is improved. There is only Ron Levy's test flights.