3 ms·

Why is it risky?

• HPsquared 4y ago
  There is not much oxygen up there and it's very cold.
• shagie 4y ago
  https://en.wikipedia.org/wiki/High-altitude_military_parachuting https://en.wikipedia.org/wiki/High-altitude_military_parachu... In military operations, HALO is also used for delivering equipment, supplies, or personnel, while HAHO is generally used exclusively for personnel. In typical HALO/HAHO insertions the troops jump from altitudes between 15,000 and 35,000 feet (4,600 and 10,700 m). Military parachutists will often reach a terminal velocity of 126 mph (203 km/h), allowing for a jump time under two minutes. ... All types of parachuting techniques are dangerous, but HALO/HAHO carry special risks. At high altitudes (greater than 22,000 feet or 6,700 metres), the partial pressure of oxygen in the Earth's atmosphere is low. Oxygen is required for human respiration and lack of pressure can lead to hypoxia. Also, rapid ascent in the jump aircraft without all nitrogen flushed from the bloodstream can lead to decompression sickness, also known as caisson disease or "the bends". --- You'll note that the numbers there are much less than 60,000 feet. The altitude here is closer to the ceiling for the U2 spy plane (famously known for being high altitude) at 70,000 or so feet. For further context with the U2, here's the pilot suit required to operate at those altitudes - https://www.afcent.af.mil/Units/380th-Air-Expeditionary-Wing/News/Display/Article/445170/u2-pilots-rely-on-special-flight-suit/ https://www.afcent.af.mil/Units/380th-Air-Expeditionary-Wing...