Accident Overview
On March 23, 2010, at approximately 0650 Pacific daylight time, a Piper PA-30 aircraft with Australian registration VHEXA sustained substantial damage after experiencing a loss of engine power during the initial climb following takeoff from Hollister Municipal Airport (CVH) in Hollister, California. The pilot, who held an Australian airline transport certificate and was the sole occupant, was not injured. Visual meteorological conditions prevailed at the time of the accident. The flight, an extended over water cross-country operation under 14 Code of Federal Regulations Part 91, was originating from Hollister with a planned destination of Kona, Hawaii, under an instrument flight rules flight plan.
Pre-Accident Events
According to the pilot's report, the day before the accident he filled the aircraft with fuel and added 30 gallons to the auxiliary bladder fuel tank for airborne system tests. He conducted a test flight to Lakeport, California, and back, during which the fuel selectors were turned to the AUX position, and engines ran on auxiliary fuel for about 15 minutes. The pilot also pumped 15 gallons of avgas from the bladder tank to the left main tank, and the right engine was switched to cross-feed, all of which functioned without incident. Upon return to Hollister, the aircraft was refueled completely, including the auxiliary bladder tank.
Accident Sequence
On the morning of the accident, the pilot started both engines, taxied to Runway 31, and activated both electric fuel pumps during the run-up. Full takeoff power was verified via tachometers and rpm gauges. After brake release, the aircraft accelerated quickly. The pilot held forward yoke pressure to ensure adequate airspeed before rotation, becoming airborne just prior to the Runway 21 intersection. After gear-up selection, the pilot maintained a shallow climb to gain airspeed. At about 60 feet above ground level, the aircraft's nose pitched up. The pilot reported that the left engine surged and lost partial power, but power was restored as the aircraft descended due to its maximum gross weight. A loud bang was heard, and the pilot pushed the throttles forward while fighting to maintain a nose-down attitude. The aircraft impacted terrain, skidded, flipped onto its back, and came to rest inverted. The pilot egressed and walked away from the wreckage; no post-crash fire occurred.
Witness and Examination
A witness reported hearing a popping noise, then observed the aircraft clear the airport boundary fence and turn left before disappearing from sight.
Inspections revealed that both propellers exhibited impact damage without rotational signatures consistent with power generation. The left engine could be fully rotated and produced thumb compression in all cylinders; the right engine had limited rotation due to impact damage. Both engines showed no evidence of pre-impact malfunction, leaks, or discoloration. Fuel selectors were found positioned to the main tanks, and fuel caps were secured. The ferry fuel tank had been removed prior to inspection, precluding examination. Magnetos on both engines were tested; the left engine fired on all cylinders, while the right engine's test was limited due to restricted rotation.
Maintenance records indicated that on March 22, 2010, a certified FAA mechanic had found the ferry fuel system fit for flight in accordance with relevant approvals.
Conclusion
Despite thorough examination, the reason for the reported loss of engine power could not be determined.