Last Saturday, a Pawans Hans single engine helicopter took off from Tawang for Itanagar. Enroute after 20 minutes the heptr lost contact with the Air Traffic Control and later crashed into the mountains killing the Chief Minister of Arunachal Pradesh and two other passengers. There were a total of five fatalities including pilots and aircraft was completely destroyed.
With the intention of spreading awareness, to enhance flight safety in this region and understand the events, an analysis, as per initial reports, of the air disaster is given in the following paragraphs. There is no intention to blame any agency or individual for the accident.
As per aviation regulations, it is not only mandatory that pilots ferrying VIPs have special training, qualifications and experience but the type of aircraft must be equipped with two engines. With the mountain peaks reaching over 20000 feet in the mountains of Arunachal Pradesh, twin engine aircraft may only operate. The helicopter ferrying Arunachal Pradesh
Chief Minister Dorjee Khandu, which crashed last Saturday, was new and registered in July last year, but it had just one engine and hence was deemed unfit for such terrain and VIP flight duties. The chopper -- AS 350 B3 of Eurocopter, nicknamed "Ecureuil", which means squirrel in French -- had a single Turbomeca engine, bore serial number 4991, was registered as VT-PHT on July 7, 2010, and pressed into service in December last year.
Aviation Safety being the top most priority, it is not understood how VIPs may force pilots to undertake flights under adverse circumstances and also how pilots may find these demands as acceptable because bending or violating flight safety rules would put the lives of everyone at risk. The Pilot-in-Command is the ultimate authority to make a final decision whether to undertake the flight, continue the flight or return to base keeping safety of the passengers and safety of the aircraft foremost in mind. Even VVIPs do not have the privilege to force pilots to undertake flights during adverse conditions. Therefore, the ultimate responsibility and authority lies with the Pilot-in-Command and a collective decision must be arrived at to ensure that safety of both aircraft and passengers are never compromised under any circumstances. The captain must exercise his authority and over rule decisions by others so that the safety of the flight is not jeopardized. So the argument that VIPs force pilots may not be acceptable since the overall responsibility and ultimate authority lies with the Pilot-in-Command.
While it is too early to come to a definite conclusion of what actually may have taken place in the absence of a full-fledged inquiry report, on the face of it and considering the circumstances and first eye witness reports under which the accident occurred and with the evidence gathered, it could have been pilot error. Pilot error does have many connotations but in this context, lack of experience and proper training of the pilots may describe the situation. Here lack of experience and training would be with reference to adequate training and sufficient flying experience in mountainous terrain of Arunachal and the North East region alongwith understanding of ever changing weather conditions. Especially so during the pre-monsoon period, should there be clouding and bad weather enroute then there would be no need to continue the flight and anyway for helicopters to enter clouds and establish Instrument Meteorological Conditions (IMC) in mountainous terrain would be suicidal. In aviation parlance, instrument meteorological conditions refers to a situation that will require the use of only instruments and other equipment inside the cockpit in the absence of external references so as to ensure and establish a safe flight path. Inability to see anything outside the cockpit due entering clouds in mountaineous terrain especially in a helicopter has many a time lead to disastrous results.
The air route from Tawang to Itanagar is south easterly and an aircraft has to negotiate Sela Pass and fly at an altitude of about 16000 feet plus and thereafter descend towards Itanagar in a south easterly heading and all the time never losing sight of ground features. What may have happened is that after takeoff from Tawang, the chopper may have entered clouds and was unable to see anything outside and on approaching Sela pass (approx 14000 feet) may have climbed to about 15000 feet inside clouds when the crew decided to return back to Tawang helipad. In the process of turning and in the absence of external references there was no way of knowing what obstruction or feature may lie ahead, the aircraft crashed into a mountain feature killing all on board including the pilots.
It would have been wise to first visually assess weather before takeoff and arrive at a final decision and refuse undertaking the flight should there be expected clouding and adverse weather enroute. Even after takeoff standard flight procedures in this mountainous sector in adverse weather conditions require that visual contact with ground is never lost and if likely to enter clouds then decision has to be made to return while all the time keeping visual contact with ground features and then carry out a safe visual landing at the helipad. However, the final investigation ports would determine and pin point the exact cause of the fatal crash so that we may learn many more lessons but the fact remains that passengers who remain mute spectators sometimes pay a heavy price.
VIA EMAIL
Wing Commander Rajeev Dong
Deputy Director Rajya Sainik Board Nagaland
