The Purcell Flightsail or Flight Dynamics Flightsail is an experimental towed glider by Thomas H. Purcell, Jr. He sold plans in several publications for the tow-launched hung-mass controllable kite-glider. He flew first off water in late 1961 and then arranged things for off-land and landing on land. His efforts would find similarity echo later in early 1963 by the SkiPlane of Mike Burns.
Development
The Flightsail is a single seat open cockpit parasol-winged glider with tricycle landing gear. The fuselage is constructed of a
triangular pyramid
In geometry, a tetrahedron (: tetrahedra or tetrahedrons), also known as a triangular pyramid, is a polyhedron composed of four triangular faces, six straight edges, and four vertices. The tetrahedron is the simplest of all the ordinary convex ...
-shaped or
tetrahedral
In geometry, a tetrahedron (: tetrahedra or tetrahedrons), also known as a triangular pyramid, is a polyhedron composed of four triangular Face (geometry), faces, six straight Edge (geometry), edges, and four vertex (geometry), vertices. The tet ...
truss; the pilot was positioned in front of the triangle-control frame. The framed flexible wing resembles a hang-glider arrangement as used on the kited gliders of
Paresev
The NASA Paresev ("Paraglider Research Vehicle") was an experimental NASA glider aircraft based upon the kite-parachute studies by NASA engineer Francis Rogallo.
Between 1961 and 1965 the ability of the Rogallo wing (also called "Parawing") to ...
program and by
Ryan Aeronautical Company
The Ryan Aeronautical Company was founded by T. Claude Ryan in San Diego, California, in 1934. It became part of Teledyne in 1969, and of Northrop Grumman when the latter company purchased Ryan in 1999. Ryan built several historically and tec ...
. The glider used weight-shift pendulum control using a stick with cables that shifts the cg of the frame relative to the wing pivoting above it. The wing is constructed with a 50-degree sweep based on NASA technical note D-443 and covered with polyethylene sheet with rip-stop fiberglass tape in a one-foot mesh pattern. The aircraft was tested by NASA test pilots
Milton Orville Thompson
Milton Orville Thompson (May 4, 1926 – August 6, 1993), ( Lt Cmdr, USNR), better known as Milt Thompson, was an American naval officer, aviator, engineer, and NASA research pilot. He was one of twelve pilots who flew the North American X-1 ...
and Victor Horton to compare against the
Rogallo wing
The Rogallo wing is a flexible type of wing. In 1948, Francis Rogallo, a NASA engineer, and his wife Gertrude Rogallo, invented a self-inflating flexible wing they called the Parawing, also known after them as the "Rogallo Wing" and flexible wi ...
being tested for space vehicle recovery.
Purcell published that in an early 1962 flight session,
Francis M. Rogallo also had a flight in the Flightsail; years later Purcell would have a very different aircraft using the flexible-wing in a modification which was flown by Francis M. Rogallo. Purcell's later
Flight Dynamics Flightsail VII used the flexible-wing in a modified format.
Specifications (Flightsail)
See also
References
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Homebuilt aircraft
Aircraft first flown in 1961
Glider aircraft