Introduction
On the morning of the accident, Keystone Air Service Ltd. Flight KEE208, a Piper PA-31-350 Chieftain (registration C-GPOW, serial number 31-7305093), was operating under instrument flight rules from Gunisao Lake, Manitoba, to Winnipeg. The aircraft carried one pilot and six passengers.
Flight Details
The aircraft had been fueled to maximum capacity the previous night at the company's base in Swan River, Manitoba. A positioning flight to Winnipeg consumed 1 hour 38 minutes, and the aircraft was not refueled upon arrival. The pilot reported for duty at 0420 central daylight time, checked weather, and filed IFR flight plans for a round trip to Gunisao Lake. He noted total fuel at approximately three-quarters of capacity. Without completing weight and balance or fuel calculations on the operational flight plan, he mentally estimated sufficient fuel for the round trip with a 50-minute reserve.
The flight to Gunisao Lake took 1 hour 31 minutes, longer than the pilot's estimate of 1 hour 20 minutes. At Gunisao Lake, six passengers and 450 pounds of baggage were boarded for the return. The pilot did not update fuel calculations. The return flight to Winnipeg took 1 hour 30 minutes.
Approach and Emergency
As the aircraft began an instrument landing system approach to Runway 13 at Winnipeg, the right engine low fuel pressure light illuminated and the engine sputtered. The pilot selected fuel cross feed, and the light went out. The pilot did not declare an emergency. He flew the approach well above the glide path and at higher-than-normal speed to allow more time to respond to a potential power loss. The aircraft broke out of clouds at about 200 feet above ground level with 3,200 feet of runway remaining but was not in position to land. The pilot executed a missed approach at 0916.
During the missed approach, the pilot switched fuel selectors to conserve fuel. The right engine lost power and was feathered. About three minutes before the crash, the pilot requested expedited return. Thirty seconds later, the left engine lost power, and he declared a 'Mayday'. The aircraft was unable to reach any runway.
Crash and Rescue
At 0920, the aircraft crashed at a major traffic intersection, striking traffic signals and several vehicles. All seven aircraft occupants and several vehicle occupants were seriously injured; one passenger subsequently died of his injuries. The aircraft sustained extensive structural damage, with wings and engines tearing off. A small post-crash fire occurred in the right wing and engine area, extinguished by bystanders with handheld fire extinguishers. Some occupants were trapped until rescue by city fire crews.
Investigation Findings
Examination of the aircraft wreckage and components revealed no pre-existing mechanical problems. Fuel pressure and flow gauges operated normally. About 8.5 US gallons of residual fuel were drained from the system. Technical records showed the autopilot had been removed on 29 April 2002 without the required journey log entries.
Company operations manual required fuel sufficient to destination, alternate, and 45-minute reserve. The pilot's pre-flight fuel estimate was incorrect; total flight time from Swan River to the missed approach was 4 hours 38 minutes, with fuel consumption averaging 225 pounds per hour. The calculated fuel remaining at Winnipeg would have been about 25 pounds (6 minutes). Engine power loss occurred 4 minutes later.
The pilot's decision to fly the ILS above glide path and at higher speed resulted in an ineffective approach. He continued beyond the missed approach point, compromising obstacle clearance.
Probable Cause
The power loss was a result of fuel exhaustion.