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Speed skydiving is a skydiving competition in which the goal is to achieve and maintain the highest possible terminal velocity. It was developed in the late 1990s and is the fastest non-motorized sport on Earth. The speed, achieved by the human body in free fall, is a function of several factors; including the body's mass, orientation, and skin area and texture. [1] In stable, belly-to-earth position, terminal velocity is about 200 km/h (120 mph). Stable freefall head down position has a terminal speed of 240–290 km/h (around 150–180 mph). Further minimization of drag by streamlining the body allows for speeds over 500 km/h (310 mph).
Speed Skydiving is a competition discipline within the sport of Skydiving. The competition objective is for the competitors to fly their body as fast as possible to achieve the highest average vertical speed through a 3 second window.
The speed is measured using a Speed Measuring Device (SMD) worn on the competitor’s helmet. The current technology used to measure the speed is GPS technology using the FlySight device (https://www.flysight.ca/). Previously (see below) barometric measuring devices were used.
The competitors exit from the competition aircraft between 13,000ft and 14,000ft (3,962m to 4,267m). Each competitor then turns 90° from the direction in which the aircraft is travelling, alternately left and right. The competitors then accelerate by flying head-first towards the earth, only slowing down once they have passed the 7,400ft competition window from their exit altitude. The score is the average vertical speed in km/h of the fastest 3 second which the competitor achieves within the competition window.
Speeding Skydiving is now one of the disciplines governed by the International Skydiving Commission (https://fai.org/commission/isc), a commission of the FAI (https://fai.org/). Before being adopted by the ISC, Speed Skydiving was governed by International Speed Skydiving Association (https://www.speed-skydiving.com/), who developed initial rules and continues to conduct competitions. The ISSA maintains eternal ranking lists for the current GPS measured events (https://www.speed-skydiving.com/index.php/rankings/eternal-ranking-gps) and one performances measured using barometric SMDs (https://www.speed-skydiving.com/index.php/rankings/eternal-ranking-barometric).
The current world record for the fastest competitor using the GPS measuring system is Marco Hepp from Germany. He flew 529.77 km/h in the competition window at the 4th FAI World Speed Skydiving Championships in October 2022. The fastest female competitor is Brianne Thompson from the United State who flew 497.80kmh (309.32mph) at the 2024 USPA National Skydiving Championships in Ottawa.
The first competition organized in the USA in Deland Florida was in 1998 with the barometric Protrack built by Larsen & Brusgaard (https://www.lbaltimeters.com/). The first speed skydiving competition in Europe [2] was organized in September 1999 at the drop zone Gap-Tallard (France) and was won by Mike Brooke. [3] [4] [5] The first international world cup was organized in 2000 [6] [7] by the ISST (International Speed Skydiving Tribe) led by Mike Brooke who pushed the sport forwards with use of two measuring devices. The devices were set on each side of the parachute of each participant instead of the foot to take away effects of dynamic air pressure on the results. An International speed skydiving world cup [8] was run in Deland (Florida), [9] Lincolnshire, UK, Botten, Switzerland, Lapalisse (France), Empuriabrava (Spain), Texel (Holland).
The terminal velocity of a falling body occurs during free fall when the force due to gravity is exactly balanced by the force due to air resistance, such that the body experiences zero acceleration. The formula for terminal velocity (where buoyancy in air is negligible) is given by the thrust
where
So, for a human in belly-to-earth position (A = 0.7 m2, m = 90 kg, Cd = 1) this gives 50.6 m/s, about the terminal velocity of the typical skydiver of 55 m/s.
The skydiver cannot increase their mass easily enough to significantly increase terminal velocity, and the skydiver's area cross-section is limited by their helmet and shoulders in a head-down dive position. The most significant difference comes from the skydiver reducing their coefficient of friction. The head-down body position has to be carefully managed to be as streamlined as possible, while special helmets and slick body suits reduce skin friction, which is a function of surface area and texture. The shape and rigidity of the suits also have to be designed to minimize the coefficient of drag. [12] Finally, a skydiver must reach their maximum speed at as high an altitude as possible so that the density of air is at a minimum.
Weather can have an extraordinary effect on a competition as well as individual divers. In the event of bad weather or air traffic circumstances, the exit altitude is lowered. In addition, thick cloud conditions may cause a delay in the jump time altogether.
A parachute is a device used to slow the motion of an object through an atmosphere by creating drag or, in a ram-air parachute, aerodynamic lift. A major application is to support people, for recreation or as a safety device for aviators, who can exit from an aircraft at height and descend safely to earth.
Free flying is a skydiving discipline that began in the late 1980s, involving falling free in various vertical orientations, as opposed to the traditional "belly-to-earth" orientation. The discipline is known to have originated when Olav Zipser began experimenting with non-traditional forms of Body flight. Zipser founded the Free Fly Clowns as a two-person competitive team with Mike Vail in 1992. He was joined by Omar Alhegelan, Charles Bryan, and Stefania Martinengo in 1994. The Free Fly Clowns are also credited with opening the first school to teach free flying, The First School of Modern Skydiving.
In classical mechanics, free fall is any motion of a body where gravity is the only force acting upon it. A freely falling object may not necessarily be falling down in the vertical direction. An object moving upwards might not normally be considered to be falling, but if it is subject to only the force of gravity, it is said to be in free fall. The Moon is thus in free fall around the Earth, though its orbital speed keeps it in very far orbit from the Earth's surface.
In fluid dynamics, the drag coefficient is a dimensionless quantity that is used to quantify the drag or resistance of an object in a fluid environment, such as air or water. It is used in the drag equation in which a lower drag coefficient indicates the object will have less aerodynamic or hydrodynamic drag. The drag coefficient is always associated with a particular surface area.
Sky surfing is a type of skydiving and extreme sport in which the skydiver wears a custom skysurf board attached to the feet and performs surfing-style aerobatics during freefall.
Terminal velocity is the maximum speed attainable by an object as it falls through a fluid. It is reached when the sum of the drag force (Fd) and the buoyancy is equal to the downward force of gravity (FG) acting on the object. Since the net force on the object is zero, the object has zero acceleration. For objects falling through air at normal pressure, the buoyant force is usually dismissed and not taken into account, as its effects are negligible.
Wingsuit flying is the sport of skydiving using a webbing-sleeved jumpsuit called a wingsuit to add webbed area to the diver's body and generate increased lift, which allows extended air time by gliding flight rather than just free falling. The modern wingsuit, first developed in the late 1990s, uses a pair of fabric membranes stretched flat between the arms and flanks/thighs to imitate an airfoil, and often also between the legs to function as a tail and allow some aerial steering.
Tracking is a technique used by skydivers during freefall to increase their horizontal speed. Tracking is considered a fundamental skill in the sport because it allows multiple skydivers to gain separation from each other prior to deploying their parachutes. Nearly all licensing organizations mandate a student show proficiency at tracking in order to obtain their skydiving license.
In fluid dynamics, drag, sometimes referred to as fluid resistance, is a force acting opposite to the relative motion of any object moving with respect to a surrounding fluid. This can exist between two fluid layers, two solid surfaces, or between a fluid and a solid surface. Drag forces tend to decrease fluid velocity relative to the solid object in the fluid's path.
Canopy piloting encompasses several disciplines, all involving the flight of a skydiving parachute.
A vertical wind tunnel (VWT) is a wind tunnel that moves air up in a vertical column. Unlike standard wind tunnels, which have test sections that are oriented horizontally, as experienced in level flight, a vertical orientation enables gravity to be countered by drag instead of lift, as experienced in an aircraft spin or by a skydiver at terminal velocity.
A set of equations describing the trajectories of objects subject to a constant gravitational force under normal Earth-bound conditions. Assuming constant acceleration g due to Earth’s gravity, Newton's law of universal gravitation simplifies to F = mg, where F is the force exerted on a mass m by the Earth’s gravitational field of strength g. Assuming constant g is reasonable for objects falling to Earth over the relatively short vertical distances of our everyday experience, but is not valid for greater distances involved in calculating more distant effects, such as spacecraft trajectories.
Freestyle skydiving is a competitive skydiving discipline where one member of a two-person team performs acrobatic manoeuvres in free fall while the other one films the performance from a close distance using a helmet-mounted camera.
Accuracy landing is one of the oldest skydiving disciplines, in which skydivers attempt to land as closely as possible to a predetermined target.
Altitude can be determined based on the measurement of atmospheric pressure. The greater the altitude, the lower the pressure. When a barometer is supplied with a nonlinear calibration so as to indicate altitude, the instrument is a type of altimeter called a pressure altimeter or barometric altimeter. A pressure altimeter is the altimeter found in most aircraft, and skydivers use wrist-mounted versions for similar purposes. Hikers and mountain climbers use wrist-mounted or hand-held altimeters, in addition to other navigational tools such as a map, magnetic compass, or GPS receiver.
Roger Warren Nelson was a skydiver, convicted drug smuggler, and founder of Skydive Chicago, one of the largest skydiving centers in the United States.
Parachuting and skydiving are methods of descending from a high point in an atmosphere to the ground or ocean surface with the aid of gravity, involving the control of speed during the descent using a parachute or multiple parachutes.
A glider or sailplane is a type of glider aircraft used in the leisure activity and sport of gliding. This unpowered aircraft can use naturally occurring currents of rising air in the atmosphere to gain altitude. Sailplanes are aerodynamically streamlined and so can fly a significant distance forward for a small decrease in altitude.
Olav Zipser is a German professional skydiver.
Skydive Empuriabrava is the brand that has been commercially operating Empuriabrava Aerodrome since 1985. Since it began operating, its main activity has been skydiving although it also offers photo flights, aerial and tourist advertising, and runs a school of aviation for private pilots.