A parafoil is a nonrigid (textile

Textile

A textile or cloth is a flexible woven material consisting of a network of natural or artificial fibres often referred to as thread or yarn. Yarn is produced by spinning raw fibres of wool, flax, cotton, or other material to produce long strands...

) airfoil

Airfoil

An airfoil or aerofoil is the shape of a wing or blade or sail as seen in cross-section....

 with an aerodynamic cell structure which is inflated by the wind. Ram-air inflation forces the parafoil into a classic wing

Wing

A wing is an appendage with a surface that produces lift for flight or propulsion through the atmosphere, or through another gaseous or liquid fluid...

 cross-section. Parafoils are most commonly constructed out of ripstop nylon.

The device was developed in 1964 by Domina Jalbert

Domina Jalbert

Domina Jalbert invented the ram-air inflated flexible wing often called the "Jalbert parafoil".-Life:Settling into Boca Raton, Florida, after arriving from Quebec, Canada, he established his business Aerology....

 (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

Parachute

A parachute is a device used to slow the motion of an object through an atmosphere by creating drag, or in the case of ram-air parachutes, aerodynamic lift. Parachutes are usually made out of light, strong cloth, originally silk, now most commonly nylon...

. It was not until the addition of a drag canopy on the riser lines (known as a "slider

Slider (parachuting)

A slider is a small rectangular piece of fabric with a grommet near each corner used to control the deployment of a "ram-air" parachute. A ram-air parachute has a tendency to open very rapidly. At high velocities, the opening shock from such a rapid deployment can cause damage to the canopy or...

") 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 hang glider

Hang gliding

Hang gliding is an air sport in which a pilot flies a light and unmotorized foot-launchable aircraft called a hang glider ....

 of the free-flight kite type

Kite types

Kites are tethered flying objects which fly by using aerodynamic lift, requiring wind, , for generation of airflow over the lifting surfaces.-Kite types:...

 and such aspects spawned paraglider

Paragliding

Paragliding is the recreational and competitive adventure sport of flying paragliders: lightweight, free-flying, foot-launched glider aircraft with no rigid primary structure...

 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, however, 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

Fédération Aéronautique Internationale

The Fédération Aéronautique Internationale is the world governing body for air sports and aeronautics and astronautics world records. Its head office is in Lausanne, Switzerland. This includes man-carrying aerospace vehicles from balloons to spacecraft, and unmanned aerial vehicles...

 (FAI) Gold Parachuting Medal for inventing the parafoil.

Parafoils see wide use in a variety of windsport

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 by aviation/maritime authorities if they are likely to...

s such as kite flying, powered parachute

Powered parachute

A powered parachute is a parachute with motor and wheels. The aircraft's airspeed is typically about 25–35 mph . PPCs operate safely at heights ranging from a few feet off the ground to altitudes as high as 18,000+ feet...

s, paragliding

Paragliding

Paragliding is the recreational and competitive adventure sport of flying paragliders: lightweight, free-flying, foot-launched glider aircraft with no rigid primary structure...

, wingsuit flying

Wingsuit flying

Wingsuit flying is the sport of flying the human body through the air using a special jumpsuit, called a wingsuit, which adds surface area to the human body to enable a significant increase in lift. Modern wingsuits, first developed in the late 1990s, create the surface area with fabric between the...

 and skydiving. The world's largest kite

Peter Lynn

Peter Lynn is a New Zealand kitemaker, engineer and inventor. He is notable for his construction of the world's largest kites , giant inflatable display kites , the popularisation of kite buggying and contributions to the development of power kiting and kitesurfing...

is a parafoil-variant.

Patents

Multi-cell wing type aerial device, filed October 1964, issued November 1966
Domina told me he got the idea for the foil while a passenger on a Lockheed Electra while looking out the window. I met him years ago in Boca Raton when we had a fire on the envelope of our Hot Air Balloon that resulted from a propane leak. Domina came up and offered the use of his shop to repair our balloon. While at his shop I saw his Jalbert Aerial Sled and this was in the late 1960's. He deserves much more credit for Aviation safety and pioneering than he gets. My credentials are FAA Parachute Rigger, United States Parachute Association Life Member, FAA A&P Mechanic, USAF and ROTC Instructor. There are others, but the main source is "The Parachute Manual" by Dan Poynter as it is the technical manual for parachute equipment world wide, and my personal relationship with Domina Jalbert, a true gentleman, in every sense of the word. He is missed like all those that are the best of humankind, remarkable and gone too soon.