Skokie was a family of research vehicles developed by the
Cook Electric Co. for the
United States Air Force
The United States Air Force (USAF) is the Air force, air service branch of the United States Department of Defense. It is one of the six United States Armed Forces and one of the eight uniformed services of the United States. Tracing its ori ...
during the mid to late 1950s. Launched from a B-29 bomber, Skokie 1 was an unpowered, ballistic vehicle, while Skokie 2 was rocket-propelled; both were used for evaluating and testing high-speed
parachute
A parachute is a device designed to slow an object's descent through an atmosphere by creating Drag (physics), drag or aerodynamic Lift (force), lift. It is primarily used to safely support people exiting aircraft at height, but also serves va ...
recovery systems.
Design and development
Intended for use in evaluating high-speed parachute systems for the recovery of missiles and unmanned aircraft,
[Jacobs and Whitney 1962, p.170.] Skokie was a simple, inexpensively-designed vehicle, consisting of a tube with a long spike on the nose to reduce damage while landing under parachute.
[Haley 1959, p.153.] Named after the hometown of the Cook Electric Co., their manufacturer, Skokie 1 had four aft-mounted stabilizing fins; Skokie 2 had a tri-fin arrangement,
[Parsch 2003] with three
solid-propellant rocket
A solid-propellant rocket or solid rocket is a rocket with a rocket engine that uses solid propellants (fuel/ oxidizer). The earliest rockets were solid-fuel rockets powered by gunpowder. The inception of gunpowder rockets in warfare can be c ...
s, of a type similar to that used for
rocket-assisted take offs, externally mounted between them.
The vehicle was equipped with instrumentation to record the deployment of the two-stage parachute; a
high-speed camera
A high-speed camera is a device capable of capturing moving images with exposures of less than second or frame rates in excess of 250 frames per second. It is used for recording fast-moving objects as photographic images onto a storage medium ...
was also fitted.
Skokie I descended ballistically at high subsonic speed; the rocket-powered Skokie II could reach
Mach
The Mach number (M or Ma), often only Mach, (; ) is a dimensionless quantity in fluid dynamics representing the ratio of flow velocity past a Boundary (thermodynamic), boundary to the local speed of sound.
It is named after the Austrian physi ...
2 before deploying its parachute.
Mission profile
Skokie was launched from a
Boeing B-29 Superfortress
The Boeing B-29 Superfortress is a retired American four-engined propeller-driven heavy bomber, designed by Boeing and flown primarily by the United States during World War II and the Korean War. Named in allusion to its predecessor, the Bo ...
bomber at in altitude.
On each drop, the vehicle would deploy an initial parachute to calibrate the onboard equipment, following which it would be released to allow the vehicle to build up speed.
[Ordway and Wakeford 1960, p.192.] A
drogue parachute
A drogue parachute, also called drag chute, is a parachute designed for deployment from a rapidly moving object. It can be used for various purposes, such as to decrease speed, to provide control and stability, as a pilot parachute to deploy ...
would be deployed once the vehicle reached a speed slightly below
terminal velocity
Terminal velocity is the maximum speed attainable by an object as it falls through a fluid (air is the most common example). It is reached when the sum of the drag force (''Fd'') and the buoyancy is equal to the downward force of gravity (''FG ...
;
[Downing 1956, p.10.] after deceleration, the main parachute of in diameter would deploy.
References
Citations
Bibliography
*
*
*
*
*
*
External links
Peaceful Missile Nose-Dives From B-29 To Test Parachute. ''
Popular Science
Popular science (also called pop-science or popsci) is an interpretation of science intended for a general audience. While science journalism focuses on recent scientific developments, popular science is more broad ranging. It may be written ...
'', June 1954, p.148.
{{USAF missiles
Experimental rockets of the United States
Equipment of the United States Air Force
Boeing B-29 Superfortress