In-flight Investigations to Evaluate the Suitability of the MCRUER Display to Conduct Mission Task Elements

Piloted evaluations form a critical part of Handling Qualities (HQ) testing. Military rotorcraft standard ADS-33 outlines the widely accepted approach to perform HQ testing, including both methods to determine predicted and assigned HQs (Ref. 1). Recently, ADS-33 has been replaced with MIL-DTL-32742, which includes updates to previously defined criteria and tasks (Ref. 2). Assigned HQs are awarded using short-look tasks, so-called Mission Task Elements (MTEs), stylized to represent mission requirements. Test courses focus on external visual cues, used by the pilot to judge position. Setting up external courses is usually expensive and may not be feasibly possible. The MCRUER (Means of Compliance Requirements for UAM Evaluations and Ratings) system intends to support HQ evaluations, replacing physical test courses using virtual displays. Four MTEs were successfully demonstrated in flight by three pilots using a variable stability rotorcraft. HQ evaluations were performed both using physical courses (live) and the MCRUER virtual courses. Handling Qualities Ratings (HQRs) were found to be consistent across both live and virtual courses with identifiable trends. Differences observed between the two cueing environments are described. Overall, virtual displays were found to improve pilot adherence to task specifications, even exceeding live-courses for a specific tasks.