The helipad is a helicopter landing pad, a landing area for helicopters. Though helicopters can usually land anywhere preferably flat (they can land on quite a slope), a fabricated helipad provides a clearly marked hard surface away from obstacles where a helicopter can land. Helipads are usually constructed out of concrete and are marked with a circle and/or a letter "H", so as to be visible from the air. Landing pads may also be constructed in extreme conditions like on frozen ice. The world's highest helipad, built by India, is located in the Siachen Glacier at a height of 21,000 feet (6400 m) above the sea level.
At 6,300 meters (20,700 feet) India controls these breathless heights at an estimated cost of up to $1 million a day and is reluctant to back off for fear Pakistan might walk in.
Yet there is no doubt the logistical and physical challenge of supplying troops at sub-zero conditions beggars belief.
The cost of supplies is a hundred times more expensive than on a normal battlefield, and India’s paying platinum rates to airlift human feces. Instead it could have bought fourteen Russian aircraft carriers. Supplying troops with a loaf of bread costs India two rupees (four U.S. cents) in the plains and 200 rupees on Siachen because it has to be taken by helicopter.
Not any ordinary helicopter but India's Indigenous Advanced Light Helicopter (ALH) that can generate lift in the extremely thin air at this altitude. The rotor blade and gearbox operate at maximum speed and pitch-angle. The engine’s maximum jet pipe temperature limits the available power. Sudden & sharp high altitude mountain gust put extreme stress on the rotor blade, lack of depth perception due to whiteout condition. Oxygen required in non-pressurized pilot cabin.
Toothpaste freezes in its tube, speech can be blurred, frostbite and chilblains are common and plummeting temperatures can leave scores dead. At these dizzying heights, breathing can also be a huge effort and many soldiers suffer from high-altitude pulmonary and cerebral edema, headaches and hypertension.
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