Here's what the Indian Army and Air Force are confronted with in the Siachen Glacier

3rd June 1990: Two Cheetah helicopters of the Indian Air Force (IAF) are on a regular air maintenance run to the Siachen glacier. As was the routine by that time — six years into Operation Meghdoot — the first shuttles were to Amar and Sonam posts, the two highest helipads on the Siachen Glacier, located at altitudes in excess of 20,000 feet above mean sea level. 

Flt Lt. B. Ramesh and Flying Officer Naresh were leading the run and were supposed to land at Sonam. Flt. Lt WVR Rao and Flying Officer Suresh Nair, in the second Cheetah, were scheduled to touch down at Amar, not very far from Sonam. 

Rao remembers that day to be slightly warmer than usual at about 10 degrees, high for the glacier, but understandable in the summer months. “At those heights, when the temperature goes beyond 5 degrees, the ‘density altitude’ at Amar and Sonam is actually close to 23,000 feet, the ultimate limit at which these helicopters can and should fly. But in those conditions, we could carry barely 5 kg load on the Cheetah. The rising temperature can have such an impact on the load carrying capacity of the helicopters,” he remembers.

Rao and Nair landed normally at Amar but as they revved up to take off, the helicopter engine ‘surged’ and the machine just sat down on the helipad. “Amar is hardly 3000 metres from a Pakistani post located at a lower altitude. Even as we were struggling to figure out what went wrong, shelling from the Pakistani post started. Remember, those were pre-ceasefire days,” Rao reminisced.

The two pilots quickly ducked inside the bunker and sent a message to the other helicopter not to come towards Amar since shelling from the Pakistani post had begun, but Flt Lt Ramesh would have none of it. He made two quick runs to Amar and evacuated Rao and Nair one by one, since it is inadvisable for anyone not acclimatised properly to stay at 20,000 feet for more than 15-20 minutes. “Ramesh landed on snow since the helipad was already occupied by our machine. He held the chopper on partial power, lest his helicopter too toppled over and lifted us away even as the ever present danger of the Pakistanis targeting the helicopter remained,” Rao says, recalling those terrifying minutes.

The pilots were back safely to the Base Camp, but problems for the Air Force were just beginning. The chopper was now stuck at Amar, a juicy target for the Pakistanis. Moreover, how does one repair a helicopter at 20,000 feet? How would the technicians get there? How long would they take to acclimatise? Normally when Army jawans get deployed at Amar or Sonam posts, they spend at least 10 days on gradually increasing altitude to get acclimatised. That luxury was however not available to the IAF technicians since the Cheetah was a sitting duck at Amar and it needed to be extracted as soon as possible.

As senior Army and Air Force officers both in Leh and Delhi put their heads together to find a quick solution to this unique problem, troops of the Sikh Light Infantry unit deployed at the Amar post overnight constructed a snow wall, a snow column really, to shield the helicopter sitting smugly on the Amar post from any Pakistani firing!

Construction of the snow wall was just the beginning of the innovation employed to retrieve the stranded helicopter from the Amar post. A team of technicians, led by Fl. Lt G. Sreepal was selected and inducted into the Glacier. Because of the urgency to repair the helicopter as soon as possible, the technical team was flown to a post at 15,000 feet for initial acclimatisation. Normally, the first stage acclimatisation for army soldiers begins at 9,000 feet. After three days of stay there, the technicians walked to a post that is located at 18,000 feet. Finally, they reached Amar on 10 June, a week after the helicopter had soft landed on the post. At the post itself, additional facilities had to be created for the arrival of the Air Force technical crew. Meanwhile, the soldiers on the post had to keep replenishing the ‘wall’ with fresh ice lest it melted away due to the strong sun, a common feature during the summer months.

Now the problem of carrying a replacement engine to Amar remained. Rao remembers: “The bosses had to select an aero engine with least starting temperature. To carry it wasn’t easy. The most powerful of the available Cheetahs with least fuel consumption was earmarked for the airlift of the engine. Now came the question of fitting in the engine in the smallish Cheetah. To overcome the problem of space, the co-pilot’s seat was removed, the engine was strapped in and the co-pilot’s seat screwed in again. At the Base camp, strapping the engine to the floor was easy since there were enough helping hands to secure the aero engine. But the same task at Amar became a challenge since the pilot would have to unscrew the seat himself and would have had to remove his gloves, a dangerous thing to do in those extreme cold conditions. Moreover, flying with the cockpit doors open — an extremely hazardous act at 20,000 feet plus altitude — was an additional worry since the cold gets accentuated at that height by the wind chill factor.” 

Despite the hazard, the most powerful of the available Cheetahs was readied. It was stripped to the bare minimum. “Out went the tail rotor guard, doors, passenger seats and the radio bay panels. The radio transmission set was removed and so was the battery after the engine was started; only two bottles of oxygen instead of the standard four that is normally carried. But that was not all. In order to save on weight, the helicopter carried fuel only sufficient to fly one way to Amar. It was planned that the refuelling for the return journey would be done at the post itself, even when the rotors would be running and the spare engine would be offloaded,” Air Commodore Anil K. Sinha, then a Squadron leader and deputy flight commander, recalls. Wing Commander Goli, the Commanding Officer and Sinha, decided to take minimum fuel for two helicopters that were to fly into Amar that morning. 

As they prepared to fly to Amar, the weather closed in, but Sinha and Goli went up to another helipad at Dolma, some three minutes flying time from Amar and waited. “As soon as the clouds cleared, Sinha flew to Amar, delivered the tools, batteries and other essential equipment before Goli landed with the spare engine. “Perhaps seeing hectic activity on the post, the Pakistanis started firing as Wing Co. Goli landed with the spare engine. It was off-loaded, refuelled even as the engine was still running.

Meanwhile at Amar, ground troops were preparing for the engine change. First they physically shifted the stranded helicopter to the very edge of the table top helipad so that the incoming helicopter with the spare engine could land and hold till the aero engine was off loaded. On 11 June, the ‘half-acclimatised’ technical crew removed the damaged engine from the stranded helicopter. Now all that they could do was wait for the replacement engine to arrive.

The technical crew worked through the evening and night of 12 June, taking help from the Sikh LI troops to change the engine. Now came the critical part: fly out the repaired helicopter. It was Friday, the 13th. 

Because of the myths associated with the date and day, the CO, late Wing Commander Goli was not sure if the operation should be carried out that day. But eventually, all of them decided that no matter what happens, they will fly out the stranded chopper that day itself. In fact, because it was a day of ‘Jumma,’ Pakistani troops were perhaps busy with their Friday prayers. Cleverly, the men on the post and the Air Force decided to fly out the helicopter around noon when they knew the adversary would be busy with the afternoon namaz. As Rao says:“Friday, the 13th did not prove to be unlucky for us at all!”

Squadron Leader (later Air Commodore) Sinha was designated to fly the stranded chopper back. He remembers: “Normally, when you are taking off, you have a space around the helicopter. Here there was no such luxury. The helicopter had had a heavy landing after its seizure and we did not know how deep it was embedded in the soft snow.  In my mind, there were many questions. Will the engine start? Will it last the flight? Will I be able to extract it and take it back to the base camp safely? As these questions swirled in my mind, I took a deep breath, started and revved the engine and took off. After we landed safely at base camp, there were impromptu celebrations!” Flt Lt WVR Rao and Flt Lt. B. Ramesh quickly followed up with a sortie and flew the technical crew back to the base camp. 

Even today, 24 years later, the unparalleled feat plays out in the minds of those who accomplished it, as if it happened just yesterday. 

Says Sinha, who went on to win a Vir Chakra for gallantry in the 1999 Kargil conflict: “That night we had a wild party at the base camps. We were doing back flips and somersaults. We were so happy and proud.” Concurs Rao, who left the Air Force in April 2012 and now flies helicopters for the Tatas in Jameshedpur: “We were almost delirious with joy. After all, how many Air Forces in the world can boast of such a deed? I remember after that long and most memorable party, my voice was so hoarse that I permanently gave up smoking!”

The event of 13 June 1990 will also go down as one of the best examples of jointmanship between the Indian Army and the Indian Air Force. Both Sinha and Rao say without the incredibly committed and selfless army soldiers on the Amar post, it would have been impossible to even think of changing the engine. “On the first day, when the chopper sat down and we came to the base camp, the Sikh LI troops on the post, at their own initiative removed the rotors blades of the helicopter and built that snow wall to keep it out of sight of the enemy. All this without any training. But a more incredible feat was yet to come. On the day we were changing the engine, the portable crane that was airlifted to Amar for hauling the engine up (remember the helicopter engine is located above the passenger seats at a considerable height) broke into pieces because of extreme cold. These brave and extremely fit Sikh LI troops physically lifted the 182-kg engine at 23,000 feet to help us repair the helicopter,” Rao said with justifiable pride.

Sinha added: “The rapport between us and the army soldiers on the glacier has to be seen to be believed. Without total trust in each other, we can never function as efficiently and effectively as we do all these years!” 

Rao also recalls the simplicity of the soldiers. “Many a times, the troops used to say they had a craving for aloo parathas. So on the days when we were coming from Leh, our wives, on a short visit to Leh, used to make them early morning and in our first flight we used to carry the aloo parathas for the troops on Amar and Sonam. The sheer joy on their faces on receiving the parathas was priceless!” Almost every helicopter pilot who has operated on the glacier would have such a story or two to share. Some remember how eager the soldiers are to receive letters from home.

In fact, a standard practice among the helicopter crew is to carry the mailbag in the very first sortie of the day since it is the lightest weight they can carry at the beginning of the day when the helicopter fuel tank is topped up full. The coordination, the camaraderie and the brotherhood of soldiers is on full display at Siachen, an emotion that civilians will never be able to fathom or understand.

The engine change and recovery of the helicopter from Amar Post is just one of the incredible feats achieved by the Siachen Pioneers, as the 114 Helicopter Unit is universally known. Established at Leh on 1 April, 1964 (this is the Golden Jubileee Year of the Unit), it has a unique distinction of being perhaps the only helicopter formation that has been deployed in an operation continuously for three decades!

Its mainstay is the single engine Cheetah (successor to the Chetak helicopter), now manufactured at the Hindustan Aeronautics Lt (HAL) facility in Bangalore. Originally produced in 1962 in France as Aerospatiale SA 319 Alouette III (known in India as Chetak), its upgraded version, the SA 315 B Lama began licensed production at HAL in 1971. This helicopter came to be known as Cheetah which is the mainstay of 114 HU since 1984. Although it has the ability to operate at the extreme flight envelope limit of 23,000 feet routinely, a single engine helicopter is fraught with risk in normal circumstances. In Ladakh and especially on the Siachen Glacier, the risks multiply manifold. 

Remembers retired AVM Manmohan Bahadur: “There are areas in the Glacier where the pilots fly with a prayer on their lips. The crevasses are so deep and wide that they could swallow an entire helicopter in the event of a forced landing. The pilots have to brave temperatures as low as minus 60 degree at times. Strong winds and poor weather is a constant companion while flying in close proximity of high peaks and rugged mountains. And don’t forget the powerful ‘down draft’ that often pulls down the machine if the pilots are not careful. In our time, over and above the regular flying at extreme flight envelope, we were also under the constant threat of enemy fire. In those days, we always flew low and fast to give minimum reaction time to the adversary. The landings then — as now — on the match box size helipads are precise. The brave jawans on those posts would open the door, take out the load, put in a casualty or mail, close the door and we would take off in reciprocal direction. The time taken for this manoeuvre was not more than 20-30 seconds! As we returned to base camp, a quick hot cup of tea, another consignment loaded and off we went again. This continued the whole day, weather permitting.”

And this routine minus the threat of enemy shelling continues even today. Every day. 365 days a year. 

Siachen Glacier

Three decades of flying in these conditions has given the 114 HU an operational experience that is envy of aviators the world over. 

Leh, it is said, is the Mecca of helicopter flying in the world. There is a saying among chopper pilots: If you are an Indian Force helicopter pilot and you haven’t been deployed to fly in Ladakh and particularly in the Siachen Glacier, you have not arrived! The lucky few, who get posted to Ladakh, are inarguably among the best helicopter pilots in the world.

Just consider this: In the 1990s, the record for highest mountain rescue in the world was from Mount Everest at 19,500 feet; Indian helicopter pilots land at 20,000 feet four times a day, every day! The Austrian Air Forces’ High Altitude Training School for helicopters is located at 9,750 feet! In India, Leh itself is at 11,000 feet!

As aviators who have had the privilege of flying under 114 HU say, ‘no amount of money can buy you the experience of landing at Sonam—the world’s highest helipad—or the satisfaction of pulling out a sick soldier battling the odds on the Glacier.’ 

Simply put, the helicopters, both of IAF and from a later date of the Army Aviation Corps, are a lifeline of Siachen. Without these machines and the magnificent flying men, India would have had great difficulty in defending the high passes on the Saltoro ridge overlooking the Siachen glacier. But it’s not easy.

The shelling may have stopped since November 2003 when India and Pakistan agreed to a ceasefire, but other challenges remain. The men and the machine continue to face the vagaries of extreme cold weather and formidable terrain. Like troops on ground, pilots too face acute mountain sickness (AMS), High Altitude Pulmonary Oedema (HAPO), High Altitude Cerebral Oedema (HACO), snow blindness, sunburns, hypothermia, chill blains and frost bite. In addition, pilots face constant discomfort and fatigue due to extreme cold (remember the temperature goes down to minus 60 in the winter), vibrations in the helicopter, risk of hypoxia, lack of concentration and as they say some times ‘white out’—a perception and spatial disorientation due to the terrain. When the glacier and its surrounding are totally covered with thick snow, pilots sometimes have no reference points while flying. In other terrains, they at least have a cliff, a valley or a flat ground as reference. But on the glacier when there is nothing but snow, just pristine white snow all over, pilots can get totally disoriented since everything around them appears two instead of three dimensional! As a pilot describes it: “The ‘white out’ can occur on a cloudy day when the skies are grey and the earth and sky appear to merge because there is no contrast of bare rocks, boulders and ridges that stand out so clearly in sunlight. Depth perception is impaired and a pilot must be careful not to get hypnotised because of concentrating too hard.”

But if pilots face the extreme odds, the machines are not spared either. Prolonged operation in the higher range of its in-built flight envelope in Ladakh has repeatedly caused structural and engine problems in the Cheetah fleet. Temperature extremes, strong winds, rarefied atmosphere has often damaged the structural frame of the helicopters. Pilots and technical officers in the Army Aviation as well as IAF have noticed frequent rupture of tubular members, cracks on welded joints; rubberised components like gaskets and seals lose their efficiency; the engines face thermal stress and are prone to—like the one that was changed on Amar—surges.

The role of the men on ground—the technicians—is perhaps more important in Ladakh than anywhere else simply because there is no margin of error in these difficult conditions. To keep an aircraft flying 6 hours a day, seven days a week means the technical and ground staff have to be constantly on their toes. The quantum of flying by helicopters under 114 HU is perhaps four times that of any other unit in the IAF. And yet, the technicians cope with the demand admirably. In sub-zero temperatures, the hands don’t work. What many of us don’t know is extreme cold can also cause ‘cold burns.’ One has to be extremely careful in handling metallic objects. If the bare skin so much as touches the metal, the skin can just get peeled off.  So gloves are a must but then all mechanical work is not possible with gloves!

A typical day at 114 HU begins an hour before sunrise. The technicians get the machines ready, checking for any small defect or shortcoming. No chances are taken. If there is even a minor fault, the helicopter is grounded. Retired Air Marshal KC Kariappa had been part of the heavy lift Mi-8 helicopter team that had supported the 1981 expedition by Col Kumar.. He later spent four days flying with 114 HU pilots in 1992. He came away awe-struck at the guts and professionalism of the pilots and the sheer dedication of the Army soldiers. 

In 1999, Air Marshal Kariappa described his experience in an article he wrote for Flight Safety Magazine in 1999. “The day would start with a 7.30 am take off from Leh to cross the 18,000 feet Khardung La. The climb out, after takeoff required all attention as we flew over the boulder-strewn narrow gullies and sometimes steep, nearly vertical slopes. There was no question of ‘relaxing’ because we were always fairly close to the ground and any malfunction demanded instant reaction to prevent the chopper from crashing. Once the pass had been crossed, I would breathe a sigh of relief as we could now start the long, shallow descent to Base Camp at the Snout of the glacier where the River Nubra had its source. In summer, the Base Camp appears unkempt; it is dirty brown and is an environmentalist’s nightmare because melting snows reveal the detritus of human habitation. But in winter all is starched, stark whiteness with only rocks that are too steep to permit accumulation of snow, breaking the monotone. On landing at Base Camp we would switch off, get the helicopter refuelled and take on a mere 25 kg of mail or other supplies for a designated picket. After takeoff and en route our destination, the colour of the glacier would change from dirty brown to almost pristine, blinding white. We could see tiny deep blue pools shimmering in the sun, and look down at the awesome, frozen and seemingly bottomless depths or forbidding crevasses from where there would be no rescue. From time to time, we would fly over small columns of troops heading up the glacier to relieve their comrades. They would be ‘roped’ to each other as a precaution, should someone stumble into a crevasse if an ice bridge were to give way....”

“After about 20 minutes of flying, the first indication that we were near our destination would be when the men there, on hearing our ‘chopper’ would light up smoke candles to indicate wind direction and its speed. The approach to land had to be perfect the first time, because in this rarefied atmosphere everything is critical: the angle of approach, the speed rate of descent and the weight of the aircraft. There is no margin for error. On touch down the engine revolutions would be decreased. The troops would scamper up quickly to off-load and within seconds we would be on our way back to Base Camp. Time is always of essence here. It is important to get in as many sorties as possible because who knows what the weather the next day would be like. For the next sorties the load would be somewhat increased, this time to perhaps 50 kg because we would be that much lighter having consumed some amount of fuel on the outbound and return legs. After four or five such missions, we would switch off to refuel during which time the technicians would check out the helicopter and prepare it for the next few sorties. While this was going on we would refresh ourselves with steaming mugs of hot tea and some food. We would then lift off again to fly a few more sorties before 1 pm. Because of topographical reasons, the valley gets extremely turbulent in the mountains. There are violent vertical currents that can toss a light helicopter like a feather in a storm...”

“A few words about the helipads: “These are located at heights varying between 14,000 and 21,000 feet. They have been stamped down and hardened by the boots of innumerable troops who then cover the surface with wooden planks to provide the firm surface needed to take the weight of the ‘chopper.’ The helipads are some 15 square feet and when viewed from air appear to be miniscule, which in fact they are. While coming in to land in the summer months, the helipad merges with the background if the approach angle is too shallow, but once the touchdown is affected, one realises that the chopper is actually sitting on a ‘table-top’ some 1.5 feet above the surrounding area. Hence, the necessity of perfect approach because a slightest error could lead to a catastrophic incident...”

Summer operations are always considered more hazardous than those in the winter because of the reduced engine power that is available to the pilot. Perhaps the analogy of driving a car whose engine is ‘tuned’ for driving in the plains and then is taken up into the hills will illustrate the point being made about the loss of power. Then there are numerous crevasses which criss-cross under one’s route and from where the chances of rescue are remote should a helicopter crash into one of them. In the winter however, the situation is very different. The engine performs much better, and the helipad sizes seem to be larger because the amount of snow has increased and had risen to the level of the helipad; even the crevasses disappear...This then is what our intrepid soldiers and airmen are confronted with in the Siachen Glacier. No amount of praise is enough and no paeans adequate to tell of their heroic deeds and acts of heroism.” 

In later years, Army also acquired the Cheetahs and Army Aviation Pilots, along with their IAF colleagues continue to serve at Siachen against all weather odds, sustaining the deployment of Indian Army troops round the year.