The Kohler Alpha is an
American,
mid-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 con ...
,
V-tail
The V-tail or ''Vee-tail'' (sometimes called a butterfly tail or Rudlicki's V-tailGudmundsson S. (2013). "General Aviation Aircraft Design: Applied Methods and Procedures" (Reprint). Butterworth-Heinemann. p. 489. , 9780123973290) of an aircraft ...
ed,
FAI Open Class
Competition classes in gliding, as in other sports, mainly exist to ensure fairness in competition. However the classes have not been targeted at fostering technological development as in other sports. Instead classes have arisen because of:
* ...
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 ...
that was designed and built by
Spud Kohler of
Cleveland, Ohio.
[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 45. Soaring Society of America
The Soaring Society of America (SSA) was founded at the instigation of Warren E. Eaton to promote the sport of soaring in the USA and internationally. The first meeting was held in New York City in the McGraw–Hill Building on February 20, 193 ...
November 1983. USPS 499-920
Design and development
Kohler built the Alpha in 1965 as a development of the
Schreder Airmate HP-11
The Schreder Airmate HP-11 is an American mid-wing, V-tailed, single seat glider designed by Richard Schreder.Said, Bob: ''1983 Sailplane Directory, Soaring Magazine'', page 19. Soaring Society of America, November 1983. USPS 499-920 Airmate ...
. He used the wings from the HP-11 and combined this with a newly designed fuselage and tail. Kohler expressed the opinion that a sailplane's performance is mostly determined by its wing, while the
fuselage
The fuselage (; from the French ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds crew, passengers, or cargo. In single-engine aircraft, it will usually contain an engine as well, although in some amphibious aircraf ...
imparts character to the design. The fuselage that he designed must have contributed to the performance, though, as the Alpha has a glide ratio two points higher than the HP-11 with the same wing.
The Alpha fuselage is made from wood, with some
fiberglass
Fiberglass (American English) or fibreglass ( Commonwealth English) is a common type of fiber-reinforced plastic using glass fiber. The fibers may be randomly arranged, flattened into a sheet called a chopped strand mat, or woven into glass clo ...
components incorporated. The fuselage uses a circular cross-section from nose to tail, with the diameter varying from the diameter at the tail to a diameter at the cockpit. The HP-11 wing is of all-metal and features a 26:1 aspect ratio, a wingspan and a
NACA
The National Advisory Committee for Aeronautics (NACA) was a United States federal agency founded on March 3, 1915, to undertake, promote, and institutionalize aeronautical research. On October 1, 1958, the agency was dissolved and its assets ...
65 (3)-618
airfoil. The v-tail is removable by first removing the tailcone and then withdrawing two pins. The controls are adapted from a
Piper PA-24 Comanche
The Piper PA-24 Comanche is an American four-seat or six-seat, low-wing, all-metal, light aircraft of semimonocoque construction with tricycle retractable landing gear. Piper Aircraft designed and developed the Comanche, which first flew on Ma ...
. The landing gear is a retractable monowheel and a tail skid. The tail skid was later replaced with a tail wheel.
Operational history
The Alpha had a number of owners and, according to
Federal Aviation Administration
The Federal Aviation Administration (FAA) is the largest transportation agency of the U.S. government and regulates all aspects of civil aviation in the country as well as over surrounding international waters. Its powers include air traffic ...
registry records was most recently transferred to the
Jimmy Doolittle Air & Space Museum at
Travis Air Force Base
Travis Air Force Base is a United States Air Force base under the operational control of the Air Mobility Command (AMC), located three miles (5 km) east of the central business district of the city of Fairfield, in Solano County, California ...
, in
Solano County, California
Solano County () is a county located in the U.S. state of California. As of the 2020 census, the population was 453,491. The county seat is Fairfield.
Solano County comprises the Vallejo–Fairfield, CA Metropolitan Statistical Area, which i ...
. The museum does not currently indicate the aircraft is part of their collection, nor is it on display.
Specifications (Alpha)
See also
References
{{reflist
1960s United States sailplanes
Homebuilt aircraft
Aircraft first flown in 1965
V-tail aircraft
High-wing aircraft