Accident Cessna 208B Supervan 900 VH-FAY,

ASN Wikibase Occurrence # 319558

Date:	Thursday 27 September 2018
Time:	15:28
Type:	Cessna 208B Supervan 900
Owner/operator:	CGG Aviation Australia
Registration:	VH-FAY
MSN:	208B0884
Year of manufacture:	2001
Total airframe hrs:	9291 hours
Engine model:	Honeywell TPE331-12JR
Fatalities:	Fatalities: 1 / Occupants: 1
Aircraft damage:	Destroyed, written off
Category:	Accident
Location:	120 km E off Sendai, Japan - Pacific Ocean
Phase:	En route
Nature:	Ferry/positioning
Departure airport:	Saipan International Airport (SPN/PGSN)
Destination airport:	Sapporo-Chitose Airport (CTS/RJCC)
Investigating agency:	ATSB
Confidence Rating:	Accident investigation report completed and information captured

Narrative:
A Cessna 208B Supervan 900, registered VH-FAY, crashed into the Pacific Ocean, at 120 km east of Sendai, Japan. The sole Norwegian pilot was missing and assumed to have died.
The aircraft was modified for geophysical survey work and converted to a Texas Turbine Conversions Supervan 900 using an 850 hp Honeywell TPE331-12JR engine (as opposed to the standard 675 hp PT6A-114A engine), and a 4-bladed prop. It was to be ferried from Jandakot Airport, Australia, to Greenwood, Mississippi, USA. After departing Jandakot on September 15, stops were made at Alice Springs, Weipa and Horn Island in Australia. It then continued to Guam and Saipan. At Saipan the pilot detected damage to the propeller anti-ice boot. The aircraft was delayed for more than a week while a company engineer travelled to Saipan and replaced the anti-ice boot.
The plane took off from Saipan, Commonwealth of the Northern Mariana Islands, USA at ca. 07:00 Japan Standard Time (JST) for the next ferry leg to New Chitose, Japan with estimated flight time of 9 hours. About an hour after departure, the aircraft levelled out at flight level FL220.
Though the position report at 10:23 JST was normally established, the next report planned at 11:44 JST was not received by the Japanese ATC. Two F-4's of Japan Air Self-Defense Force noticed the aircraft flying normally at 14:50 JST over the Pacific Ocean, but could not establish any radio contact with the flight. The JASDF pilots were unable to see into the cockpit to determine whether the pilot was in his seat or whether there was any indication that he was incapacitated.
After about 30 minutes, the JASDF pilots observed the aircraft descend into cloud. The aircraft descended rapidly and disappeared from radar less than 2 minutes later. Within 2 hours, search and rescue personnel located the aircrafts rear passenger door. No other aircraft parts were located and the pilot was not found.

The ATSB concluded that while the aircraft was in the cruise on autopilot, the pilot almost certainly became incapacitated and did not recover. About 5 hours after the last position report, without pilot intervention to select fuel tanks, the aircrafts engine stopped, likely due to fuel starvation. This resulted in the aircraft entering an uncontrolled descent into the ocean.
The cause of incapacitation could not be determined. While a medical event could not be ruled out, the pilot was operating alone in an unpressurised aircraft at 22,000 ft and probably using an unsuitable oxygen system, which increased the risk of experiencing hypoxia and being unable to recover.

Contributing factors:
- During the cruise between Saipan and New Chitose, the pilot very likely became incapacitated and could no longer operate the aircraft.
- The aircrafts engine most likely stopped due to fuel starvation from pilot inaction, which resulted in the aircraft entering an uncontrolled descent into the ocean.

Accident investigation: