Ми-8 RA-25607 14.07.2013

Accident date	14.07.2013
Investigation status
Aircraft registration number	RA-25607
Place of aircraft departure
Airport of departure
Intended destination
Intended Airport of arrival
Accident site	in Kargasoksy district of the Tomsk region
Latitude	N 57°44,291'
Longitude	E 76°25,556'
Aircraft type	MI-8
Serial №
Aircraft operator
Aircraft owner	"Gazpromavia" aviation enterprise" Ltd
The date of the completion of the investigation (report)	21.12.2016
Number of fatalities	0
Victims accuracy
Degree of aircraft destruction	aircraft substantially damaged
Report	report_ra-25607.pdf (3.42 MB)
Aviation type	Commercial
Works type	Aerial works
Note

15 july 2013

     The accident with Mi-8 RA-25607 helicopter owned by "Gazpromavia" aviation enterprise" Ltd occurred in Kargasoksy district, Tomsk region (RF) on July 14, 2013. Three crew members and 14 passengers were on board. According to the preliminary information first officer and passengers suffered injuries of various degrees of severity, the rotorcraft was partially destroyed.
     The Interstate Aviation Committee has assigned the Investigation team of the accident in accordance with the Russian Aviation Legislation. The Investigation team has started its work.

23 july 2013

      Flight recorders of Mi-8T RA-25607 helicopter involved in the accident in the Tomsk region (RF) on July 14 were delivered to the Interstate Aviation Committee on Julyn18.
      The Interstate Aviation Committee experts carried out activities on data recovery and readout on July 18-22, 2013.
      All FDR and Navstar receiver recorded data was copied and transferred to the Investigation team for further analysis.
      All read voice data contained on MC-61 tape recorder reels detected at the accident site does not refer to helicopter operation on July 14, 2013.

22 december 2016

Most probably the accident with Мi-8Т RA-25607 helicopter was caused by crew uncoordinated actions during take-off resulted in helicopter accelerated left rotation and its ground impact.

Contributing factors could be:

• PIC helicopter control intervention without providing information to the rest of the crew;

• partial loss of situational awareness and/or spatial disorientation in helicopter accelerated left rotation.

Hazard factors were identified in course of the investigation: autopilot connector contamination due to its leakage and specific operating performance wide-range scatter of RA-60B actuator prototype in control directional axis (in compliance of each particular prototype with requirements) which in certain conditions can significantly increase inflight emergency situation risk. However no aeronautical equipment failure evidence which could effect emergency flight result were identified.

The appropriate safety recommendations based on the investigation results were developed.