The Schreder HP-20 is an
American,
high-wing
A monoplane is a fixed-wing aircraft configuration with a single mainplane, in contrast to a biplane or other types of multiplanes, which have multiple planes.
A monoplane has inherently the highest efficiency and lowest drag of any wing co ...
,
T-tail
A T-tail is an empennage configuration in which the tailplane is mounted to the top of the fin. The arrangement looks like the capital letter T, hence the name. The T-tail differs from the standard configuration in which the tailplane ...
, single seat
glider
Glider may refer to:
Aircraft and transport Aircraft
* Glider (aircraft), heavier-than-air aircraft primarily intended for unpowered flight
** Glider (sailplane), a rigid-winged glider aircraft with an undercarriage, used in the sport of glidin ...
designed by
Richard Schreder
Richard E. Schreder (25 September 1915 – 2 August 2002) was an American naval aviator and sailplane developer, responsible for design and development of the HP/RS-series kit sailplanes marketed from 1962 until about 1982. Schreder also fou ...
.
[Said, Bob: ''1983 Sailplane Directory, ]Soaring Magazine
''SOARING'' is a magazine published monthly as a membership benefit of the Soaring Society of America. It was first published in 1937. The headquarters is in Hobbs, New Mexico. The magazine's article topics include safety issues and accounts of in ...
'', page 24. Soaring Society of America, November 1983. USPS 499-920
Design and development
The HP-20 was designed by Schreder for the
FAI 15 Metre Class. The HP-20 prototype was just complete when Schreder lost interest in the project and moved on to work on the
HP-21
The HP-21 was a scientific calculator produced by Hewlett-Packard between 1975 and 1978. It was designed as a replacement for the HP-35, and was one of a set of three calculators, the others being the HP-22 and HP-25, which were similarly built ...
instead. The sole example of the HP-20 was built by Schreder in his workshop in
Byran, Ohio and first flew in 1981.
The HP-20 is all-metal with foam wing ribs. The design shares a similar fuselage to the
HP-19, but has a different double-tapered wing of smaller area, versus for the HP-19. This gives the HP-20 a higher wing loading and higher best glide speed, although the glide ratio is the same as the HP-19 at 42:1. The
airfoil is a Schreder modification of a Wortmann section, designated as ''Schreder 3''. of water ballast can be carried. The landing gear is a retractable monowheel.
Operational history
Even though Richard Schreder died in August 2002, in April 2011 the sole HP-20 was still registered to him.
Specifications (HP-20)
See also
References
{{Schreder Sailplanes
1980s United States sailplanes
Schreder aircraft
Aircraft first flown in 1981