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The GFM or POH provides useful information about recommended power settings and target airspeed for best angle of climb, best rate of climb, best cooling performance climb, and cruise performance while in powered flight. If full throttle operation is time limited to reduce engine wear, the GFM/POH describes the recommended operating procedures. Aircraft performance includes weight and balance limits, minimum and maximum front seat weight restrictions, maximum permitted airspeed with engine extended, maximum airspeed to extend or retract the engine, flap operating airspeed range, air brake operating airspeed range, maneuvering speed, rough air speed limitations, and never-exceed speed. 

The engine heats up considerably during takeoff and climb, so cooling system mismanagement can lead to dangerously high temperatures in a short time. An overheated engine cannot supply full power, meaning climb performance is reduced. Extended overheating can cause an inflight fire. To minimize the chances of engine damage or fire, monitor engine temperatures carefully during high power operations, observing engine operating limitations described in the GFM/POH. 

Many self-launching gliders have a time limitation on full throttle operation to prevent overheating and premature engine wear. If the self-launching glider is equipped with cowl flaps for cooling, make certain the cowl flaps are set properly for high power operations. In some self-launching gliders, operating at full power with cowl flaps closed can result in overheating and damage to the engine in as little as 2 minutes. If abnormally high engine system temperatures are encountered, follow the procedures described in the GFM/ POH. Typically, these require reduced power with higher airspeed to enhance engine cooling. Cowl flap instructions may be provided as well. If these measures are ineffective in reducing high temperatures, the safest course of action may be to shut down the engine and make a precautionary landing. A safe landing, whether on or off the airport, is always preferable to an inflight fire. 

Handling limitations for a given self-launching glider may be quite subtle and may include minimum controllable airspeed with power on, minimum controllable airspeed with power off, and other limitations described in the GFM/POH. Self- launching gliders come in many configurations. Those with a top-mounted retractable engine and/or propeller have a thrust line that is quite distant from the longitudinal axis of the glider. The result is that significant changes of power settings tend to cause substantial pitch attitude changes. For instance, full power setting in these self-launching gliders introduces a nose-down pitching moment because the engine thrust line is high above the longitudinal axis of the glider. To counteract 

this pitching moment, the pilot holds the control stick back pressure and trim. If power is quickly reduced from full power to idle power while holding an control up stick force, the glider tends to pitch up with the power reduction. This nose- pitching moment may be vigorous enough to induce aircraft stall. Smooth and coordinated management of power and flight control provides the safest procedure under these conditions. 

During climb-out, the pilot should hold a pitch attitude that results in climbing out at the desired airspeed, adjusting elevator trim as necessary. As previously stated, climbs in self-launching gliders are best managed with smooth control inputs; when power changes are necessary, make smooth and gradual throttle adjustments. 

When climbing under power, most self-launching gliders exhibit a left or right turning tendency (depending on whether the propeller is turning clockwise or counterclockwise) due to P-factor. P-factor is caused by the uneven distribution of thrust caused by the difference in the angle of attack (AOA) of the ascending propeller blade and the descending propeller blade. Use the rudder to counteract P-factor during climbs with power. [Figure 7-25] 

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Turns are accomplished with a shallow bank angle because steep banks result in a greatly reduced rate of climb. As with all turns, properly coordinated aileron and rudder movement result in a more efficient flight and faster climb rate. The pilot should scan for other aircraft traffic before making any turn. Detailed engine shutdown procedures are described in the GFM/POH. A guide to shutdown procedures is described below, but the GFM/POH is the authoritative source for any self-launching glider. 

Engines reach high operating temperatures during extended high-power operations. To reduce or eliminate shock cooling 

