Accident Antonov An-2R RA-33017,

ASN Wikibase Occurrence # 320682

Date:	Wednesday 18 September 2013
Time:	07:34
Type:	Antonov An-2R
Owner/operator:	Taksavia
Registration:	RA-33017
MSN:	1G218-04
Year of manufacture:	1986
Total airframe hrs:	5277 hours
Cycles:	24822 flights
Engine model:	Shvetsov ASh-62IR
Fatalities:	Fatalities: 0 / Occupants: 7
Aircraft damage:	Substantial, written off
Category:	Accident
Location:	48 km W of Nyagan - Russia
Phase:	Landing
Nature:	Passenger - Non-Scheduled/charter/Air Taxi
Departure airport:	Arbyn Airfield
Destination airport:	Nefteyugansk Airport (NFG/USRN)
Investigating agency:	MAK
Confidence Rating:	Accident investigation report completed and information captured

Narrative:
An Antonov 2R plane sustained substantial damage in a forced landing accident following a loss of engine power. Three occupants were injured.
The airplane was owned by Sosvapromgeologiya. Because this company did not have a licence to perform commercial flights, a planned passenger flight was being operated by Taksavia. The An-2 departed Surgut at September 12 on a flight to Saranpaul and Arbyn before planning a return to Surgut. The last leg was planned for September 18. Since Surgut was closed, the destination was changed to Nefteyugansk Airport (NFG). The flight took off at 06:10. At 07:20 hours, at an altitude of 700 m the crew noticed that the cylinder head temperature rose to 220°-230°C and then to about 305°C. The oil temperature rose to 90°C. Power was lost and the captain decided to perform a forced landing on moorland. The airplane nosed down into a swamp.

Cause (translated from Russian):
Most likely cause of the accident with the An-2 RA-33017 was the use of substandard car fuel, low-octane, presence of mechanical impurities (rust), which led to an increase in the temperature of the cylinder heads, drop in engine power, unintentional reduction of altitude and the need to perform a forced landing on the wetland.
Contributing factors could be:
- poor organization of storage, refueling and fuel quality control on site;
- wrong decision by the captain to perform the flight when detecting that the fuel deviated from the norm (color, texture, presence of mechanical impurities).

Accident investigation: