Editing Parachute (section)

=== Round ===
[[File:USMC Paratrooper.jpg|thumb|upright|An American [[paratrooper]] using an MC1-1C series "round" parachute.]]

Round parachutes are purely a drag device (that is, unlike the ram-air types, they provide no [[lift (force)|lift]]) and are used in military, emergency and cargo applications (e.g. [[airdrop]]s). Most have large dome-shaped canopies made from a single layer of triangular cloth [[Gore (segment)|gores]]. Some skydivers call them "jellyfish 'chutes" because of the resemblance to the marine organisms. Modern sports parachutists rarely use this type.
The first round parachutes were simple, flat circulars. These early parachutes suffered from instability caused by oscillations. A hole in the apex helped to vent some air and reduce the oscillations. Many military applications adopted conical, i.e., cone-shaped, or parabolic (a flat circular canopy with an extended skirt) shapes, such as the United States Army [[T-10 parachute|T-10]] static-line parachute. A round parachute with no holes in it is more prone to oscillate and is not considered to be steerable. Some parachutes have inverted dome-shaped canopies. These are primarily used for dropping non-human payloads due to their faster rate of descent.

Forward speed (5–13&nbsp; km/h) and steering can be achieved by cuts in various sections (gores) across the back, or by cutting four lines in the back, thereby modifying the canopy shape to allow air to escape from the back of the canopy, providing limited forward speed. Other modifications sometimes used are cuts in various gores to cause some of the skirt to bow out. Turning is accomplished by forming the edges of the modifications, giving the parachute more speed from one side of the modification than the other. This gives the jumpers the ability to steer the parachute (such as the United States Army MC series parachutes), enabling them to avoid obstacles and to turn into the wind to minimize horizontal speed at [[landing]].