Hope for survivors on missing IAF aircraft fast vanishing
Since July 22, 2016 an AN-32 aircraft of the Indian Air Force (IAF) with 29 personnel on board is reported missing.
The aircraft was on a routine courier flight from Tambaram (Chennai) to Port Blair (Andaman and Nicobar islands).
It took off at 8.30am and was expected to arrive at its destination at 11.30am covering a total distance of 1,375km between Chennai and Port Blair.
The last Very High Frequency (VHF) R/T contact between the aircraft and air traffic control at Chennai was at 8.46am. The last radar contact was at 279km from Chennai.
Experts are indicating the probable cause of accident as mechanical failure, fuel leakage or a fire that may have disabled the controls.
These reasons are being attributed to no emergency R/T call. The situation may have been so catastrophic that the crew was incapacitated and was unable to give an emergency call.
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| The AN-32 did not transmit on the International Distress Frequency. This frequency could have been received by satellites, ships and aircraft. |
"Request weather deviation to the right." Those were the last words of the AN-32 aircrew heard at the air traffic control at 8.46am before the aircraft disappeared from the radar at 9.15am, with a rapid loss of altitude from 21,000 feet.
This leads me to believe that the aircraft had entered into bad weather. The satellite picture over that area gave insignificant information on the weather, but there may have been embedded cumulus (vertical) clouds, in the layers of stratus clouds.
The most probable cause of the accident could be attributed to departure of the aircraft from controlled flight owing to an external weather related phenomenon. The inquiry committee would ascertain the actual cause.
The secondary radar picture at the Chennai air traffic control could clearly establish the pattern of rapid descent of the aircraft. If the aircraft had spiralled down with very little ground speed and no forward movement, then the probability of fire and mechanical failure could be eliminated.
The aircraft did not transmit on the International Distress Frequency. This frequency could have been received by satellites, ships and aircraft.
The two ELTs (Emergency Locator Transmitter) were not triggered. This system should have transmitted on impact with water.
These transmissions would have been received at MRCC (Maritime Control Centre) at Cochin and Chennai, through the Indian Space Research Organisation (ISRO). The aircraft also had five dinghies and 55 life vests to support the passengers for sea survival.
The Air Force, Navy, Coast Guard, merchant vessels and hydro ships have been pressed into the search operations.
C130, C-17, P8I and Dornier aircraft have been scouting the area for locating the missing plane.
However, it is important that these ships and aircraft have sensors on board for locating the debris.
The state of the sea at this time of the year with fast currents and high winds makes survival difficult. The debris also moves away from original impact site rapidly, making it difficult for search and rescue operations.
The CDR (Crash Data Recorder) or popularly known as "black box" must be located to ascertain with high probability the cause of the accident. The CDR transmits a signal on land or sea through which its location can be ascertained. No transmission from the CDR has been received by any agency so far.
I can give no better example in locating the black box than of the Air France Flt 447 from Rio de Janeiro to Paris, which crashed over the Atlantic Ocean on June 1, 2009.
The Airbus 330 with nearly 300 passengers on board was flying at 35,000 feet, from where it crashed into the sea.
The French investigation agencies located the black box at a depth of about 3.5km on the sea bed.
Submersible side scan sonars were used which could see at a distance of 700m. The recovery of the black box was possible because it was sending strong signals of its presence.
Through the black box the exact cause of the accident was positively ascertained. Corrections have been made in Airbus systems which could perhaps have saved many lives thereafter.
Then on May 25, 2011, a PC-12 aircraft with ten personnel on board crashed at Faridabad, after entering into bad weather. The inquiry report is available on the DGCA website. It makes interesting reading.
After nearly 150 hours that AN-32 went missing, the hope for any survivors is fast diminishing. At this time we can only hope for a miracle.