||High Altitude/High Opening (HAHO) can only be carried out by highly-trained parachutists who can navigate in the air.
Troops leap from an aircraft above 30,000ft and possibly across an international border so that they reduce the chances of the aircraft being identified. At this height (Mount Everest stands 29,000ft high) soldiers require oxygen and specialist clothing.
Within seconds of jumping, the team open parachutes and then perform a series of navigational turns to remain on target.
Each team member must check speed and direction and anticipate what moves to stay within range of each other and the target landing site.