The Indian Government has received a detailed report on the Sept. 2, 2009 fatal helicopter crash in the south Indian state Andhra Pradesh that killed Y.S.R. Reddy, 60, chief minister of Andhra Pradesh, and four others, Reddy’s principal secretary and chief security officer as well as the two chopper pilots.

Their twin-engine Bell 430 went missing after it took off from Begumpet Airport in Hyderabad city and headed to Chittoor district, both in Andhra Pradesh, in heavy rain.

The Indian Government had appointed a four-member Committee of Inquiry headed by Shri R.K. Tyagi, Pawan Hans Helicopters, to investigate the crash of the Bell 430 helicopter (BT-APG). The other members of Committee were Capt. Irshad Ahmed, Flight Operations Inspector, Directorate General of Civil Aviation, Shri Sanjay Bramhane, Senior Air Safety Officer, Directorate of Air Safety, DGCA Mumbai with Shri Maneesh Kumar, Dy. Director of Air Safety, DGCA as the member secretary of the committee.

During the course of investigation, the investigation team undertook technical analysis at the crash site for evidences and also at the Andhra Pradesh Aviation Corporation Limited (APACL) Hanger at Hyderabad for reconstruction/tear-down analysis of various helicopter components and systems.

Various technical inputs/analysis were coordinated with Airports Authority of India (AAI), Indian Air Force (IAF), Indian Meteorological Department (IMD), National Aeronautical Laboratories (NAL), Bangalore and Defence Metallurgical Research Laboratories (DMRL), Hyderabad.

Central Bureau of Investigation (CBI) provided help for certain analysis with Central Forensic Science Laboratories (CFSL), Hyderabad. India Precision Lightning Network, New Delhi provided technical inputs about the electric charge scenario of the areas around the site on the day of crash.

Technical support was provided by the Transport Safety Board (TSB) of Canada, The U.S. National Transportation Safety Board (NTSB), Bell Helicopters, Goodrich, and Rolls Royce.

The Probable Cause of the accident was determined to be "loss of control resulting in uncontrolled descent in the terrain at a very high rate of descent due to entry into severe down draught."

Contributory factors were:

  • The crew flew in Instrument Flying condition though flight plan was cleared for Visual Flight Rules (VFR).
  • The crew was engrossed for six minutes before the crash searching for a checklist from the Flight Manual. This distracted their attention from the prevailing poor visibility weather conditions thus leading into the loss of situational awareness.