A parafoil is a nonrigid (
textile
Textile is an Hyponymy and hypernymy, umbrella term that includes various Fiber, fiber-based materials, including fibers, yarns, Staple (textiles)#Filament fiber, filaments, Thread (yarn), threads, different #Fabric, fabric types, etc. At f ...
)
airfoil with an aerodynamic cell structure which is inflated by the wind. Ram-air inflation forces the parafoil into a classic
wing
A wing is a type of fin that produces lift while moving through air or some other fluid. Accordingly, wings have streamlined cross-sections that are subject to aerodynamic forces and act as airfoils. A wing's aerodynamic efficiency is e ...
cross-section. Parafoils are most commonly constructed out of
ripstop nylon.
The device was developed in 1964 by
Domina Jalbert (1904–1991). Jalbert had a history of designing kites and was involved in the development of hybrid balloon-kite aerial platforms for carrying scientific instruments. He envisaged the parafoil would be used to suspend an aerial platform or for the recovery of space equipment. A patent was granted in 1966.
Deployment shock prevented the parafoil's immediate acceptance as a
parachute. It was not until the addition of a drag canopy on the riser lines (known as a "
slider") which slowed their spread that the parafoil became a suitable parachute. Compared to a simple
round canopy, a parafoil parachute has greater steerability, will glide further and allows greater control of the rate of descent; the parachute format is mechanically a
glider
Glider may refer to:
Aircraft and transport Aircraft
* Glider (aircraft), heavier-than-air aircraft primarily intended for unpowered flight
** Glider (sailplane), a rigid-winged glider aircraft with an undercarriage, used in the sport of gliding
...
of the free-flight
kite type and such aspects spawned
paraglider
Paragliding is the recreational and competitive adventure sport of flying paragliders: lightweight, free-flying, foot-launched glider aircraft with no rigid primary structure. The pilot sits in a harness or lies supine in a cocoon-like ...
use.
The air flow into the parafoil is coming more from below than the flight path might suggest, so the frontmost ropes tow against the airflow. When gliding, the angle of attack is lowered and the airflow meets the parafoil head on. This makes it difficult to achieve an optimum gliding angle without the parafoil deflating.
In 1984 Jalbert was awarded the
Fédération Aéronautique Internationale (FAI) Gold Parachuting Medal for inventing the parafoil.
Parafoils see wide use in a variety of
windsport
A windsport is any type of sport which involves wind-power, often involving a non-rigid airfoil such as a sail or a power kite. The activities can be land-based, on snow, on ice or on water. Windsport activity may be regulated in some countries b ...
s such as
kite flying,
powered parachute
A powered parachute, often abbreviated PPC, and also called a motorized parachute or paraplane, is a type of aircraft that consists of a parafoil with a motor and wheels.
The FAA defines a powered parachute as ''a powered aircraft a flexible or ...
s,
paragliding,
kitesurfing,
speed flying,
wingsuit flying and
skydiving.
The
world's largest kite is a parafoil-variant.
Today, SpaceX uses steerable Parafoils to recover the Fairings of their Falcon 9 Rocket on two ships, GO Ms. Tree and GO Ms. Chief.
Patents
* ''Multi-cell wing type aerial device'', filed October 1964, issued November 1966
See also
*
Foil kite
References
{{Reflist
Aerospace engineering
Parachuting
Aircraft wing design
Parafoils
Kites