A year after four persons were killed when a Border Security Forces (BSF) Chetak helicopter crashed near Mount Abu in Rajasthan,findings by the Director General of Civil Aviation (DGCA) have revealed that logbooks of the aircraft had not been maintained for five years and there was a serious lapse regarding proficiency check of the co-pilot.
This was not the first time that Chetak helicopters had crashed,the report said. In 1978-79,two Chetak copters crashed after the failure of hydraulic drag damper.
The helicopter owned by the BSF was manufactured in 1989 by Hindustan Aeronautics Limited,Bangalore. The probe committee found that the same helicopter was involved in heavy landing on January 30,2005,and the crew had then reported severe vertical and lateral vibrations.
The impact of the crash was such that the crew and the passengers did not get any time to react and there was an intense fire that engulfed the entire cockpit. Those killed were identified as pilot Colonel (Retd) Bal,co-pilot Deputy Commandant Vivek Chaudhary,engineer S S Chopra and sub-inspector Sohanlal. The incident was reported on May 13,2011.
The report said BSF had operations and maintenance contract with Pawan Hans Helicopters Limited (PHHL),but on scrutiny it was found neither party was exercising any operational control due to which no crew-related records/ documents were maintained by any of the party.
The logbooks of PHHL for the years 2005 to 2010 were not available.
It appears that PHHL did not exercise any quality control over the maintenance activities. They did not possess copies of the maintenance manual and other technical literature for preparing and updating the aircraft maintenance program on the basis of which call outs are required to be issued. There was frequent rotation (weekly/fortnightly) of the technicians at the outstation maintenance bases. The rotation of the personnel was carried out without any consideration for the relevant skill,level of experience and to ensure the continuity in the maintenance activity, the report said.
It said the snag could not be detected at initial stage because there was no proper record of the maintenance of the equipment called hydraulic drag damper (which causes severe vibrations)
Inspection of the BSF store inventory indicated that they do not have equipment for the drag damper timing check. Neither was there any record of their procuring such equipment. This indicates that their
assessment of drag damper timing was based on estimation and not actual measurements. Therefore the snag may not have been detected at its initiations, said the