ANALYSIS OF ARMY HELICOPTER PILOT ERROR MISHAP DATA AND THE IMPLICATIONS FOR HANDLING QUALITIES∗

This paper describes a survey of US Army pilot error mishap data to determine if trends show any implications for handling qualities. The work was motivated by two considerations: First, the increasing accident rates, especially at night and in degraded visual environments. Second, the ongoing opportunity to upgrade two of the current fleet, the cargo CH-47 Chinook, and the utility UH-60 Black Hawk. Data used was US Army Safety Center summaries of pilot error mishaps for the period 1986-1996, for the AH-64A, CH-47D, H-60 (includes the UH-60A, UH-60L, and MH-60L) and the OH-58D. Summaries were reviewed and the mishap situations assigned to several categories related to task difficulty, situation awareness and visual environment. The results suggest that poor handling qualities can exist while performing hover and low speed tasks, especially in degraded visual environments, and should be considered a potentially hazardous condition. Piloted simulation studies have shown that handling qualities improvements are possible with stability and control augmentation schemes which give an attitude command response type. Recent investigations suggest that the benefits of attitude command can be obtained even with the limited authority stability and control augmentation systems existing in the current fleet. Except for the AH-64A Apache, mishaps in low speed maneuvering flight were much more prevalent than accidents that start from hover. This suggests that hover position hold alone would not significantly reduce the accident rate.