The weather that day, though misty at some places close to the destination, was totally fit for flying, especially for a Master Green pilot, who must have flown through such weather a very large number of times. The weather and the visibility were within the flying limitations of the pilot.
New Delhi: The tragedy in the Nilgiris of the crash of the MI17 helicopter on 9 December, involving CDS Gen Bipin Rawat, his wife and his team and the chopper crew has again reminded us of the saying that if aviation is one of the most romantic human ventures, then an aviation accident or an air crash is equally one of the most unfortunate tragedies. This uncanny relationship prepares any aviator under training to the inevitability of this phenomenon and its ghastly repercussions if one is not prepared for it.
All aviation training institutions the world over, whether military or civil, prepare their trainee pilots to face air emergencies of any sort, the theory behind these and related corrective actions, so that a safe landing can be executed with minimum loss of lives and equipment.
The number of emergencies in aviation are many and relate to the type of aircraft and the mission it is undertaking.
Hence, we can in a general sense divide these into, 1) engine related, its handling and subsequent total failure including engine fir; 2) emergencies related to airframe and the systems which operate the flying services like hydraulics, brakes, etc; 3) electric related emergencies which may involve the flying instruments and also the control surfaces; 4) fire emergencies; 5) emergency related to weather, i.e., bad weather and its repercussions. Though bad weather is not an emergency in itself, but could develop into one if not handled efficiently, therefore all pilots are made proficient to fly on instruments without any outside references so as to execute safe flying to their respective destinations while in clouds and bad weather.
The trainee is made to study all the systems and thus practise handling all these on the ground and in simulators till he or she scores not less than 100% in emergency tests. One must note that these emergencies may not come singly, but could be multiple in nature like engine failure and bad weather, or hydraulic failure and fire in the air or some other combination. A pilot is made to study and practise on these regularly to get total confidence in handling these. There are special establishments particularly in all Air Forces which conduct inspection visits, and test all the flying crew on a flying base periodically. Handling of emergencies is a main part of the test.
This now brings us to the tragic Mi17 crash in the Nilgiris.
Mi17 V5 is used for the travel of VVIPs the world over because of various safety provisions provided in it, including safety from hostile fire, or various emergencies. Its airframe is designed with special composite material to withstand high degrees of impact in case of an unfortunate crash This is to ensure the safety of the passengers within. This chopper is equipped with advanced avionics and can operate in any geographical area, be it the high mountains, jungles, desert or over the sea. It has a glass cockpit, which includes state of the art avionics, four multifunctional displays (MFDs), night vision equipment, onboard weather radar and an efficient autopilot system, including navigation information display and cueing system. The cockpit and the critical components are protected by a heavy armour plating. It has self-sealing fuel tanks which are explosion proof. Engine exhaust suppressors, infrared (IR) are all part of this aircraft.
The pilot flying the chopper was Wing Commander P.S. Chauhan the Commanding Officer of the Helicopter Unit 109, and one of the most experienced helicopter pilots, along with his co-pilot Squadron Leader K. Singh, also a very experienced pilot.
The sudden accident on that day on a flight which involved less than half an hour of flying from the IAF base at Sulur to Wellington helipad in Coonoor, has baffled everyone and led to the common practice of conjecturing about the cause of the accident, and the cause is guessed as bad weather. The weather that day, though misty at some places close to the destination, was totally fit for flying, especially for a Master Green pilot, who must have flown through such weather a very large number of times. The weather and the visibility were within the flying limitations of the pilot.
It is a well established practice in the realm of military or civil aviation to call in for a court of inquiry to accidents, and in Air Force there is an independent Air Accident Board (AAIB), which conducts a separate investigation. The court of inquiry goes through all the required points related to the aircraft, the crew, the weather and even if there was possibility of sabotage.
The AAIB and the court of inquiry (COI) go through all the facts available at the starting base—all the documents related to the health and history of the aircraft, all the previous snags, any recurring snags, any part requiring replacement, whether all the required modifications had been incorporated as per the proper procedure. The state of the fuel supplied for refuelling is collected for examination.
All the details of the flying crew, the pilot’s medical fitness, flying category, and if any doubt about his mental condition that day would be found out through established methods of even talking to the family members.
The AAIB and the COI then visit the crash site and studies the wreckage. The study of the spread of the wreckage and the point of impact reveals a lot for an expert on the job. It can be established as to what the altitude was during the crash. Was it a vertical descent or a flattish approach? Was the engine running or was it a case of engine failure? The way the pieces have twisted and burnt can reveal the angle and speed of impact. All this is gathered on the ground so that a proper study is conducted and photographed.
This is further established by the black box or the flight data recorder, which reveals all the recorded details of the speed of the aircraft, altitude, engine parameters of RPM and temperature, oil and fuel parameters on a time map scale till the point of impact.
Most importantly, the recorded conversation of the pilots in the cockpit and the conversation with the departure point and the destination are examined. Here the cockpit voice recorder (CVR) plays a very important role. Both the black box and the CVR of the ill-fated chopper have been located.
At this juncture one has to give time to this tri-service court of inquiry to finish the job along with the AAIB findings to come to a logical conclusion. Before that it would be totally counterproductive to guess the cause of the crash, which would lead to unwanted rumours of all kinds.