Performance Analysis and Flight Testing for Low Altitude Long Endurance Unmanned Aerial Vehicles

摘要

The objective of this paper is to study the performance of a low altitude long endurance UAV. One of the important aspects of performance analysis is the optimal speeds for maximum endurance and/or maximum range. With DATCOM method, although the drag coefficient of the UAV can be determined, the resulted maximum endurance is found to be much longer than the data obtained from the flight tests. The problem is caused by the landing gears of which the drag is not counted in the DATCOM analysis. To eliminate the error, by referring to results of flight tests, a correction method for the drag coefficient to include the effect of the landing gears is suggested and the optimal cruise speeds for the maximum endurance and the maximum range are determined accordingly. It is found that the speeds should be as slow as possible. This result is quite different from the typical case in which the optimal speed usually lies in between the minimum and the maximum possible ones.