Conceptual Design of MALE UAVs

The conceptual design process of aircraft involves the creation of a product, in this case UAVS (unmanned aerial vehicles), using the most effective means possible across multiple subdisciplines of Aerospace Engineering. This paper will outline a unique methodology that involves calculating certain design variables such as wing loading, power loading, aspect ratio and cruise altitude in the conceptual design phase for MALE (medium altitude long endurance) UAVs. Aircraft characteristics from MALE UAVs such as the MQ-9 predator and MQ-1 reaper will used for a comparative aircraft study as “jumping off” points in order to carry out the initial calculations. An intensive computational computer program was created to perform the appropriate calculations in an iterative process. These calculations, details outlined in this paper, involved the usage of both empirical and analytical weight equations, to calculate the s (structural factor), and series of aerodynamic equations, to calculate the L/Dcrs (Lift over Drag at cruise) which are both the termination criteria. The iterative process mainly involves cycling through numerous aspect ratios, wing loadings and cruise altitudes to generate a family of aircraft that can be plotted against lines of constant TOGW (take-off gross weight) and design constraint such as Landing and Takeoff distances. The most efficient design can then be derived within the bounds of the design constraints at the lowest TOGW. Due to the intensive computational nature of the analytical method for calculating the weight of the wing, a cluster computer made up of a series of Raspberry PIs was developed to ease the computational time. This unique design process was able to successfully allow the user to generate a MALE UAV within certain design constraints per user request.