Overview
On Sunday, October 12, 2014, at approximately 14:30 Japan Standard Time, a Cirrus SR20 aircraft registered as N176CD and owned by Korea Pilot School sustained damage during a forced landing in a grass field in Nishikata, Ibusuki City, Kagoshima Prefecture, Japan. The aircraft was being ferried from Saipan International Airport to Gimpo International Airport in the Republic of Korea. The pilot, who was contracted for the ferry flight, was the sole occupant and reported no injuries. The aircraft was destroyed but did not catch fire.
Flight Details
The aircraft departed Saipan International Airport at about 05:37 JST under visual flight rules, with an intended route via NATSS, G339 airway, Kagoshima VORTAC, A582 airway, and Anyang VOR. The flight plan indicated a total estimated elapsed time of 12 hours 30 minutes, with fuel onboard for 15 hours 35 minutes. Prior to departure, the pilot filled the main wing tanks with a total of 56 gallons, the front ferry tank with 38 gallons, and the rear ferry tank with 70 gallons, for a total of 164 gallons. After takeoff, the pilot sequentially used the right wing tank, left wing tank, and then switched to the rear ferry tank about one hour after departure.
Engine Failure and Forced Landing
At around 14:19 JST, while approaching the KINKO reporting point near Kinko Bay, the pilot noticed the engine sound surging and the fuel flow gauge fluctuating. The aircraft, which had been maintaining altitude via autopilot, began to descend. The pilot, suspecting low fuel in the rear ferry tank, switched to the front ferry tank but the surging continued. Approximately 15 to 20 seconds later, the engine stopped and the fuel flow indicator showed zero. The propeller continued windmilling at about 1,500 rpm.
The pilot attempted to restart the engine by activating the auxiliary fuel pump in the BOOST position and following the airstart procedures from the Pilot's Operating Handbook, but the engine did not restart. He then switched to the right and left wing tanks and attempted airstart procedures again, without success. At 14:19:53, the pilot declared an emergency to Kagoshima Radar and requested radar vectors to the nearest airport. The aircraft continued descending, and at 14:29:46, its groundspeed became zero. The forced landing occurred in a grass field.
Probable Cause
According to the Japan Transport Safety Board, it is highly probable that the accident resulted from the engine halting during flight and the inability to restart it in the air, leading to damage during the forced landing. The engine halt was somewhat likely caused by fuel exhaustion in the rear ferry tank, leading to power loss. When the pilot opened the fuel selector valve for the front ferry tank (which still contained fuel) without closing the rear ferry tank's valve, air from the empty rear tank entered the fuel line due to suction from the engine-driven fuel pump, hindering fuel supply. The inability to restart the engine in the air was somewhat likely because the air in the fuel line made it difficult for the engine-driven fuel pump to suck fuel, and the auxiliary fuel pump could not quickly remove the air that obstructed the pump's suction.