Parachute Systems

There are essentially two different parachute systems: round canopy parachutes and surface parachutes. Basically, both systems can be used individually, are used for rescue, and as a last parachute.

Round canopy parachutes

The older round canopy parachutes reduce the speed of the fall almost exclusively through their big air resistance. Its shape resembles a hollow open at the bottom hemisphere at its lower edge, and it has suspension lines to which a parachutist, or the payload, is attached. At its peak there is an opening (apex opening) through which pent-up air can escape to avoid a collapse of the chute.

For a sink motion chute, an ordinary-round canopy parachute is perpendicular to the surface and simply replaced by a horizontal component of wind drift. Earlier the sports field used high round-cap systems that provided slits to allow air to flow forward through them. The flow could be varied via control lines, and the slot opening of the parachute controlled to a limited extent.

Due to the high risk of injury from the high rate of descent and limited control features, round canopy parachutes found little use by civilians. In addition to use by the military for a quick withdrawal of paratroops and dropping loads from low altitudes, they are used almost exclusively as a brake or emergency parachute for paragliding and hang glider pilots, as well as gliders, aerobatic flight or total recovery systems from micro-light aircraft and small private aircraft.

Parachutes here are almost never used as for stopping, but mostly slow down an object. So there are no braking parachutes, but simply parachutes.

As rescue systems, the chutes have been unchanged since 1940. Reserve systems should be regularly checked by trained personnel, and repackaged within their pack at intervals (from two to twelve months). After use, a rescue system may be re-packed by trained personnel. The lifetime of a parachute in use is ten years.

Rescue parachutes must be tested thoroughly; a positive test result extends their life, one time, by two years. After the expiry of twelve years of total service life, the rescue systems are retired.

Ballistic Recovery Systems are required for ultralights in Germany. For small private aircraft, however, they are still banned.

Surface Parachutes (including Gliding Parachutes)

Modern parachutes reduce the surface sink mainly due to buoyancy. Their cross-section corresponds to an airplane wing. The chute area is open at the front edge and closed at the rear, so that it will be filled by the oncoming air and stiffened. Therefore, these umbrellas are also known as ram-air slide parachutes, or colloquially as a mattress or surface parachute.

Once the forward speed is large enough, a flow is located, which also gives buoyancy to the air resistance. Therefore, surface parachutes do not fall perpendicular to the ground, but can partially overcome due to their large horizontal glide lines. The right and the left side of the trailing edge can be separated by steering lines pulled down and then perpendicularly to the front of oncoming air.

This makes the forward motion slow and be exactly controlled on one side of the chute. At landing, the forward motion is slowed by a strong pulling down on both edges of parts in the optimum case to zero. In the sports area, surface parachutes are now used almost exclusively.

Parachutes are the most common use of the nylon fabrics “F-111″ and “Zero-P” (zero porosity: no air permeability, zero tissue) or combinations produced from them. At the ends of the parachute (with a round canopy) or below the surface (for surface systems), suspension lines are attached, on which depends the cargo or the parachutist.

The life span of a parachute is shortened by solar radiation. This amounts to approximately 1,000 (F-111) to more than 3,000 jumps (Zero-P).