Incident Overview
On August 14, 2019, at approximately 0725 mountain standard time, an Extra Flugzeugbau EA 300L airplane, registration N19AM, sustained substantial damage during an accident near Mesa, Arizona. The aircraft was operated by Aviation Performance Solutions, LLC, under Title 14 Code of Federal Regulations Part 91 as an instructional flight. The flight instructor and the pilot receiving instruction were not injured.
Sequence of Events
The flight instructor reported that a loss of engine power occurred at an altitude of 6,700 ft above ground level, immediately after he demonstrated a rolling maneuver as part of the Upset Prevention and Recovery Training profile. Following the power loss, the flight instructor switched the fuel selector valve from the WING position (wing fuel tanks) to the ACRO/CENTER (acrobatic) fuel tank position, which indicated just below full. He then turned the airplane toward Phoenix Mesa Gateway Airport (KIWA) and declared an emergency with the tower, noting that the engine was still developing partial power based on cockpit indications.
Approximately 4 minutes after the partial loss of engine power, and about 1 minute before touchdown, a further reduction in engine performance occurred. The flight instructor observed a decrease in airspeed and an increased descent rate. He informed the tower and confirmed that the emergency fuel boost pump was activated. Ultimately, the flight instructor made an off-airport landing, and the airplane impacted terrain in a nose-low attitude.
Wreckage and Fuel System Examination
Onsite examination by Federal Aviation Administration (FAA) inspectors revealed that the airplane landed on rough, uneven desert terrain with heavy brush-like vegetation. The main wing assembly sustained impact damage, but the wing fuel tanks remained intact with no evidence of fuel leakage. The aircraft's fuel system consisted of separate and independent sources: interconnected wing tanks for normal operations and an acrobatic/center fuel tank in the fuselage. The wing and acro/center fuel tank filler caps were secure and in place, with no fuel leakage from the center tank assembly.
Fuel measurements showed the acro/center tank contained approximately 13 gallons of avgas, the left-wing tank contained trace amounts, and the right-wing tank contained approximately 6 gallons of avgas.
Engine and Fuel Pump Investigation
The airframe and engine were examined on November 21, 2019, by representatives from the National Transportation Safety Board, FAA, and Lycoming Engines. The engine showed nominal impact damage, and a functional test run was attempted using an external fuel source. Multiple attempts to start the engine to a sustained idle power setting were unsuccessful.
Investigation determined that the electric fuel boost pump was inoperative and not delivering rated fuel flow. The aircraft was equipped with a mechanical engine-driven fuel pump for normal operations and an electrically driven boost pump for emergencies and inflight restarts. After the electric boost pump was replaced with a separate unit, the engine started and ran continuously at varied throttle positions from idle to full power. Once running, the electric boost pump was switched off, and the engine continued to operate solely on the mechanical fuel pump without anomalies.
Fuel Pump Failure
Examination of the removed electric boost pump by representatives from the manufacturer (Weldon Pump) and the FAA revealed that the pump had been originally manufactured by Weldon Pump of Cleveland, Ohio, and subsequently overhauled by Aeromotors, LLC, an FAA repair station. The original manufacture date could not be determined, but records indicated the boost pump was overhauled by Aeromotors on August 8, 2018, and replaced on July 15, 2019, approximately 27 flight hours before the accident flight. Disassembly and examination showed that the blade/vane retaining ring had failed, rendering the pump inoperative.
Aircraft Manual Guidance
The airplane flight manual states that aerobatic maneuvers must be accomplished with the fuel selector in the ACRO/CENTER (acrobatic) fuel tank position and prohibits aerobatic maneuvers with the wing fuel tanks selected.