Date & Time: Jun 27, 2010 at 1545 LT
Type of aircraft:
PZL-Mielec AN-2
Operator:
Registration:
RA-62631
Flight Phase:
Flight
Survivors:
Yes
Site:
Plain
Schedule:
Voskresensk - Voskresensk
MSN:
1G178-23
YOM:
1978
Country:
Russia
Region:
Asia
Crew on board:
2
Crew fatalities:
0
Pax on board:
1
Pax fatalities:
0
Other fatalities:
0
Total fatalities:
0
Aircraft flight hours:
3208
Circumstances:
Crew was performing a survey flight while in a fire fighting program. In flight, engine failed and crew elected to make an emergency landing. Eventually, aircraft stalled and crashed in the Varnavka River. Both pilots and the passenger were injured while the aircraft sunk and was damaged beyond repair.
Probable cause:
The accident was the result of a forced landing on the water surface due to unstable operation of the engine after a loss of power which was caused by the re-enrichment of the fuel-air mixture because of jamming of the needle valve of the left float chamber of the carburetor. The most probable reason for jamming of the needle valve of the left float chamber is its clogging by foreign particles that resulted from failure to comply with section 2.02.01.20 of the rules of maintenance of the AN-2 while performing 100-hour maintenance works due to lack of RTO requirements for mandatory compliance.

Source : ASN