U.S. special operators have several ways to get to work.

Green Beret teams can do free-fall jumps with oxygen from 25,000 feet, and Navy SEAL squads can spend up to eight hours in mini-submarines on combat dives.

One of the least known methods of insertion and exfiltration is the “helocast,” an airborne special-operations technique used by small commando elements to insert into semi- or non-permissive areas.