NTSB Factual Report

On June 4, 2018, about 1152 Pacific daylight time (PDT), a turbine-powered, Australian registered, GippsAero GA10 airplane, VH-XMH, was destroyed after it impacted terrain following an unrecoverable spin during a flight test near Mojave, California. The United States certificated Airline Transport Pilot, and Australian certificated Commercial Pilot, sustained minor injuries after both successfully bailed out of the airplane. The airplane was registered to and operated by GippsAero as a visual flight rules test flight under the provisions of 14 Code of Federal Regulations Part 91.715 Special Flight Authorization when the accident occurred. Visual meteorological conditions prevailed, and company flight following procedures were in effect. The flight originated at the Mojave Air and Space Port (KMHV), Mojave, California, about 1105 PDT.

The purpose of the flight was to evaluate the spin characteristics of the GippsAreo GA10 airplane with a belly-mounted cargo pod installed. Additionally, the accident airplane was equipped with an anti-spin parachute to be used if an unrecoverable spin was encountered, and both pilots wore emergency parachutes.

A chase airplane was used to follow and monitor the progress of the flight test.

According to the flight test pilot, the accident flight was the ninth flight that he participated in during the one-turn spin evaluations of the GA-10 fitted with the cargo pod. He said that after departure, a stall series was completed prior to any spin entries, with stall characteristics normal and benign.

The pilot reported that the first spin entry was initiated with wings level, power on, with flaps set to a landing configuration, which was followed by left rudder and right aileron inputs. The pilot said that the spin recovery took longer than expected, and the decision was made to repeat the test. The next spin entry produced very similar results, with the recovery at one additional spin turn. The accident flight spin entry was flown in the same configuration as the first two spins, except that the entry was from a 30° bank left turn. The pilot reported that the airplane entered a normal spin, and after one spin turn, he applied flight control inputs for the spin recovery; however, the airplane settled into a fully developed spin.

The pilot said that after the airplane attained three full spin turns, he heard the chase airplane personnel call "three turns" which was a predetermined flight test safety limit. The pilot reported that he then moved the control yoke full forward with full opposite rudder and right aileron in an attempt to arrest the spin, but to no avail. He said that the control yoke was then returned to neutral, then full forward and full right rudder. Around 10,000 ft msl, the pilot heard the chase airplane personnel call "chute, chute, chute" instructing the flight test crew to deploy the emergency anti-spin parachute. The pilot said that when the anti-spin parachute deployment lever was pulled aft, the anti-spin parachute did not deploy, even after repeated attempts. At about 8,500 ft msl, which was 500 ft. above the briefed minimum bailout altitude, both pilots bailed out.

The closest weather reporting facility was KMHV, about 9 miles north of the accident site. At 1200, a METAR from KMHV was reporting, in part: wind from 300° at 15 knots, gusting 20 knots; visibility, 10 statute miles; clouds and sky condition, clear; temperature, 93° F; dew point 39° F; altimeter, 29.91 inches of mercury.

The closest weather reporting facility was KMHV, about 9 miles north of the accident site. At 1200, a METAR from KMHV was reporting, in part: wind from 300° at 15 knots, gusting 20 knots; visibility, 10 statute miles; clouds and sky condition, clear; temperature, 93° F; dew point 39° F; altimeter, 29.91 inches of mercury.