The Johnson RHJ-6 Adastra (English: ''Star'') was 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 wings.
A monoplane has inherently the highest efficiency and lowest drag of any wing config ...
, two-seat
glider that was designed and constructed by
Dick Johnson and first flown on 3 April 1960.
Design and development
The Adastra was conceived by Johnson as a two-place competition aircraft. He completed and flew it in 1960.
The aircraft was of mixed construction. The
fuselage
The fuselage (; from the French language, French ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds Aircrew, crew, passengers, or cargo. In single-engine aircraft, it will usually contain an Aircraft engine, engine as wel ...
was built from wood and was a
monocoque
Monocoque ( ), also called structural skin, is a structural system in which loads are supported by an object's external skin, in a manner similar to an egg shell. The word ''monocoque'' is a French term for "single shell".
First used for boats, ...
design. The wing had a wooden structure, with
fiberglass
Fiberglass (American English) or fibreglass (English in the Commonwealth of Nations, Commonwealth English) is a common type of fibre-reinforced plastic, fiber-reinforced plastic using glass fiber. The fibers may be randomly arranged, flattened i ...
leading edge
The leading edge is the part of the wing that first contacts the air;Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', page 305. Aviation Supplies & Academics, 1997. alternatively it is the foremost edge of an airfoil sectio ...
. The tail surfaces were constructed of wood. The wings aft of the leading edge, the tail surfaces and all control surfaces were covered with doped
aircraft fabric
Aircraft fabric covering is a term used for both the material used and the process of covering aircraft open structures. It is also used for reinforcing closed plywood structures. The de Havilland Mosquito is an example of this technique, as are ...
.
Originally the aircraft employed an Eppler 150
airfoil
An airfoil (American English) or aerofoil (British English) is a streamlined body that is capable of generating significantly more Lift (force), lift than Drag (physics), drag. Wings, sails and propeller blades are examples of airfoils. Foil (fl ...
section, but Johnson later modified it by adding a 10% wing chord extension, turning the airfoil into an Eppler 151. Later new wings were built with an Eppler 414 airfoil to improve low-speed performance. The new wings used a foam-filled fiberglass leading edge. The tail was originally a "Y" tail, but this was later replaced with a conventional tail, with a low-mounted
tailplane
A tailplane, also known as a horizontal stabilizer, is a small lift (force), lifting surface located on the tail (empennage) behind the main lifting surfaces of a fixed-wing aircraft as well as other non-fixed-wing aircraft such as helicopters ...
.
The individual cockpits were covered with independent
bubble canopies, although the aircraft was most often flown solo, with a flat hatch replacing the rear canopy to reduce
aerodynamic drag
In fluid dynamics, drag, sometimes referred to as fluid resistance, is a force acting opposite to the direction of motion of any object moving with respect to a surrounding fluid. This can exist between two fluid layers, two solid surfaces, or b ...
. In 1983 it was reported that a single canopy was being designed for the aircraft.
Only one Adastra was built.
Operational history
In its original configuration Johnson flew the Adastra in the 1960
World Gliding Championships
The World Gliding Championships (WGC) is a gliding competitions, gliding competition held roughly every two years by the FAI Gliding Commission. The dates are not always exactly two years apart, often because the contests are always held in the sum ...
in
Cologne
Cologne ( ; ; ) is the largest city of the States of Germany, German state of North Rhine-Westphalia and the List of cities in Germany by population, fourth-most populous city of Germany with nearly 1.1 million inhabitants in the city pr ...
,
West Germany
West Germany was the common English name for the Federal Republic of Germany (FRG) from its formation on 23 May 1949 until German reunification, its reunification with East Germany on 3 October 1990. It is sometimes known as the Bonn Republi ...
and finished in 15th place. After extending the wing chord and altering the airfoil he flew it in the US Nationals to a seventh-place finish in 1961 and second place in 1962.
The aircraft was later owned by Jesse Womack of
Graham, Texas
Graham is the county seat of and largest city in Young County. As of the 2020 U.S. Census, it has a population of 8,732.
History
The site was first settled in 1871 by brothers Gustavus A. and Edwin S. Graham, primary shareholders in the Texas E ...
. The
Federal Aviation Administration
The Federal Aviation Administration (FAA) is a Federal government of the United States, U.S. federal government agency within the United States Department of Transportation, U.S. Department of Transportation that regulates civil aviation in t ...
registry records indicate that the aircraft was destroyed and was removed from the registry on 6 April 1992. The
National Soaring Museum
The National Soaring Museum (NSM) is an aviation museum whose stated aim is to preserve the history of motorless flight. It is located in Big Flats Town, New York, on top of Harris Hill near Elmira.
The NSM is the Soaring Society of America's ...
lists the aircraft as being part of their collection and in storage.
Aircraft on display
*
National Soaring Museum
The National Soaring Museum (NSM) is an aviation museum whose stated aim is to preserve the history of motorless flight. It is located in Big Flats Town, New York, on top of Harris Hill near Elmira.
The NSM is the Soaring Society of America's ...
- listed as "in storage"
Specifications (Adastra - later configuration)
See also
References
*
*
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*{{cite web, url=http://www.soaringmuseum.org/collection.html , title=Sailplanes in Our Collection , accessdate=17 May 2011 , last=
National Soaring Museum
The National Soaring Museum (NSM) is an aviation museum whose stated aim is to preserve the history of motorless flight. It is located in Big Flats Town, New York, on top of Harris Hill near Elmira.
The NSM is the Soaring Society of America's ...
, authorlink= , year=2011 , url-status=dead, archiveurl=https://web.archive.org/web/20110516142717/http://www.soaringmuseum.org/collection.html , archivedate=16 May 2011
1960s United States sailplanes
Homebuilt aircraft
Aircraft first flown in 1960
Mid-wing aircraft