Unmanned Aerial System Handling Qualities Framework Applicability to Heavy Gross Weight Mission-Configured UAS

Abstract

Unmanned Aerial Systems (UAS) are becoming more prominent across both commercial and military applications, and the need to define handling qualities requirements for assessing vertical lift UAS ability to meet mission demands is essential. The UAS handling qualities requirement must be scalable and apply to the wide range of airframe configurations across their operational flight envelopes, due to the increasing variety of unmanned or optionally manned systems. Flying and handling qualities criteria are well defined in ADS-33E-PRF for manned vertical lift aircraft, where the predictive requirements and mission task elements have proven effective on a wide range of aircraft with varying configurations, sizes and loading configurations. A similar robustness is needed in an effective vertical lift UAS handling qualities framework. This paper builds upon previous work towards a scalable vertical lift UAS handling qualities framework by evaluating the robustness of this framework on a representative range of Group 1 UAS in various sizes, configurations, and loading conditions. Two group 1 UAS, a hexacopter (1.8 ft hub-to-hub) and a single main rotor Synergy 626 (4.6 ft rotor diameter) were extensively evaluated with the framework, using two mission task elements each, evaluated across a range of mission and empty weight configurations, with low and high aggressiveness. A third Group 1 UAS, a coaxial (8 propeller) quadcopter (1.83 ft hub-to-hub), was evaluated with the framework in a mission weight configuration at nominal aggressiveness. The key outcomes of the work are updated time-to-complete specifications that are more consistent with waypoint navigation, validation of MTE courses and performance specifications at alternate loading conditions, and validation of the robustness of the Froude-scaled ADS-33E-PRF Level 1 attitude bandwidth and disturbance rejections bandwidth metrics as predictive requirements.