An IAF An-32 with 29 personnel (6 air crew and 23 passengers) on board went missing on July 22, 2016 while flying from Chennai to Port Blair. The aircraft belonging to 33 Squadron took off from Air Force Station Tambaram, near Chennai at 8.30 on a 3-hour flight to Port Blair in the Andaman and Nicobar Islands.
At 9.12 am, when the aircraft was around 300 km off Chennai cruising at 23,000 ft., its radar track indicated a sharp left turn with a rapid loss of height. The aircraft has since been untraceable despite a massive search and rescue (SAR) operation underway.
The An-32 is a medium lift transport capable of hauling 6.7-ton cargo or 39 fully geared paratroopers cruising at 470-kph. The Indian Air Force acquired 125 aircraft starting from the mid-80s. Over a hundred are still in service.
The An-32 aircraft is fitted with two powerful engines that give it good high altitude performance. Air maintenance requirements of army units deployed along the LoC and LAC, have made the An-32 an IAF workhorse. However, because of the powerful engines, a ride in the aircraft is characterized by high vibration and noise levels.
In June 2009, India signed a $400 million agreement with Ukraine's Ukrspetsexport to overhaul and upgrade its entire fleet of 105 AN-32's.
The upgrade would extend the life of the aircraft from 25 years to 40 years, increase maximum payload from 6.7 ton to 7.5 ton, reduce cockpit noise and vibration to enhance crew comfort, and upgrade aircraft avionics.
Under the agreement, 40 An-32s would be upgraded at designer certified plants in Ukraine, with 10 aircraft being upgraded annually.
The remaining 64 An-32s would be upgraded at IAF's No. 1 Base Repair Depot (BRD) at Kanpur using material and ToT by Ukraine.
In December 2009, India signed a separate three-year contract worth $110 million with Motor Sich OJSC (Zaporizhia) for upgrade of the AI-20 engines fitted on the Indian An-32s.
The upgrade at Kiev has since been completed. Upgrade at No. 1 BRD is currently ongoing.
The upgraded An-32s, referred to as An-32REs, have new radars with MFDs, air collision avoidance system, ground proximity warning system, satellite navigation, distance measuring equipment, upgraded radio altimeters, new oxygen systems and improved crew seats.
Flight Safety Record
Since induction in the mid-80s, IAF AN-32 aircraft have crashed on 11 occasions. During the period from March 1986 to March 1992, 5 IAF An-32s crashed. Two crashes were catastrophic in nature raising doubts over the structural integrity of the aircraft.The accident rate abated dramatically thereafter, with subsequent accidents being attributed to pilot error or weather.
Since 1992, the An-32 built quite a reputation as a rugged and safe workhorse.
Latest Accident - The Relevant Facts
Considering the oceanic depths along most of the route it may not be possible to recover the black box and establish the cause of the accident. Weather and catastrophic failures are two possibilities, the latter more remote than the former.
No distress call was ever received by ground control. Either the pilots didn't make a distress call, or their distress calls went unheard. At 280-km range, radar horizon would have been several thousand feet above sea level. It would not have been possible to track the aircraft down to sea level. The ill-fated aircraft could have recovered from the spiral and flown some more. We don't know yet !!
An analysis of the radar track before the steep descending turn would be revealing. Minor deviations in the track could be indicative of pilot disorientation due to weather followed by total loss of control. A steady radar track would point towards catastrophic failure.
The An-32RE is equipped with an all weather radar. The pilots would have been aware of any hazardous weather ahead, provided the radar was tuned and set properly. Wrong weather radar setting can result in a misleading weather displays. There are unconfirmed reports that the pilot sought a weather based deviation from track.Despite a well set weather radar, pilots can enter bad weather. For example, when flying through what is called a 'bowling alley'. The gap between two adjacent cumulonimbus (Cb) cells can close while the aircraft is transiting through the gap.
The aircraft was a RE variant recently overhauled and upgraded at No. 1 BRD so a catastrophic failure cannot be ruled out.
As Air Chief Marshal Arup Raha said in his recent statement, "Events like these are painful reminders of the inherent risks which our brave personnel face in the execution of our daily missions."
There is no reason to believe the An-32 will not serve as the IAF workhorse for many more years to come.