Aparafoil is a nonrigid (textile)airfoil with an aerodynamic cell structure which is inflated by the wind.Ram-air inflation (created by dynamic air pressure from the parachute's motion through the air) forces the parafoil into a classicwing cross-section. Parafoils are most commonly constructed out ofripstop nylon.
The device was developed in 1964 byDomina 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.[1]
Deployment shock prevented the parafoil's immediate acceptance as aparachute. It was not until the addition of adrag canopy on the riser lines (known as a "slider") which slowed their spread that the parafoil became a suitable parachute. Compared to a simpleroundcanopy, a parafoil parachute has greater steerability, will glide further and allows greater control of the rate of descent; the parachute format is mechanically aglider of the free-flightkite type and such aspects spawnedparaglider use.[2]
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 2019 Jalbert was awarded posthumously theFédération Aéronautique Internationale (FAI) Gold Parachuting Medal for inventing the parafoil.[3]
Parafoils see wide use in a variety ofwindsports such askite flying,powered parachutes,paragliding,kitesurfing,speed flying,wingsuit flying andskydiving.[2][4][5][6] Theworld's largest kite is a parafoil-variant.[7]
Today, SpaceX uses steerable Parafoils to recover the fairings of theirFalcon 9 rocket.
History of the Powered Parachute, Powered Parachute Terms, Aerodynamics Summary, etc.