Accident Overview
An aircraft conducting an FAA certification test flight experienced a runway excursion while attempting a landing with simulated hydraulic systems inoperative at Yuma International Airport in Yuma, Arizona. The aircraft departed the right side of runway 21R and came to rest approximately 6,700 feet beyond the landing threshold.
Flight Purpose
The flight was part of an FAA certification test to demonstrate compliance with a special condition under 14 CFR Part 25. The objective was to show that the aircraft could be controlled and landed safely with a complete failure of its hydraulic systems.
Sequence of Events
The aircraft touched down about 1,735 feet beyond the threshold of runway 21R. The pilot deployed the thrust reversers and applied reverse thrust before the nosewheel had contacted the runway. The aircraft then began to yaw, and the yaw continued after the nosewheel touched down. Subsequently, the aircraft ground looped to the right and slid off the right side of the runway.
Damage and Injuries
The aircraft sustained substantial damage initially and was later described as damaged beyond repair. All three crew members were slightly injured; there were no passengers on board. Weather conditions at the time were clear with a dry runway.
Probable Cause
The official probable cause cited inadequate procedures established for the certification test flight and the pilot's mismanagement of thrust following the initial loss of directional control.