The EEL ULF 1 is a
West German
West Germany is the colloquial term used to indicate the Federal Republic of Germany (FRG; german: Bundesrepublik Deutschland , BRD) between its formation on 23 May 1949 and the German reunification through the accession of East Germany on 3 O ...
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 ...
, single-seat, foot-launched,
microlift 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 by
Dieter Reich. When it was available it was provided in the form of plans by
Entwicklung und Erprobung von Leichtflugzeugen (EEL) ( en, Development and Testing of Light Aircraft) for
amateur construction. By the end of 2019 the company website had been take down and it is likely that the company has gone out of business.
[Bertrand, Noel; Rene Coulon; et al: ''World Directory of Leisure Aviation 2003-04'', page 56. Pagefast Ltd, Lancaster OK, 2003. ISSN 1368-485X]
Design and development
The ULF 1 was first flown in November 1977 and first shown at the 3rd International Hang Glider Meet at the
Wasserkuppe
The is a mountain within the German state of Hesse. It is a large plateau formation at an elevation of and is the highest peak in the Rhön Mountains. Great advances in sailplane development took place on the mountain during the interwar pe ...
in August 1978. The prototype was built by Reich's partner at EEL, Heiner Neumann. The design was intended to be able to
soar in weak ridge and thermal lift.
The aircraft is made from
spruce
A spruce is a tree of the genus ''Picea'' (), a genus of about 35 species of coniferous evergreen trees in the family Pinaceae, found in the northern temperate and boreal (taiga) regions of the Earth. ''Picea'' is the sole genus in the subfami ...
,
birch
A birch is a thin-leaved deciduous hardwood tree of the genus ''Betula'' (), in the family Betulaceae, which also includes alders, hazels, and hornbeams. It is closely related to the beech-oak family Fagaceae. The genus ''Betula'' contains 30 ...
plywood and
balsa
''Ochroma pyramidale'', commonly known as the balsa tree, is a large, fast-growing tree native to the Americas. It is the sole member of the genus ''Ochroma''. The tree is famous for its wide usage in woodworking, with the name ''balsa'' being ...
, covered in
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 ...
and features conventional full three axis controls. Its two-piece, single-
spar
SPAR, originally DESPAR, styled as DE SPAR, is a Dutch multinational that provides branding, supplies and support services for independently owned and operated food retail stores. It was founded in the Netherlands in 1932, by Adriaan van Well, ...
span wing is a
cantilever
A cantilever is a rigid structural element that extends horizontally and is supported at only one end. Typically it extends from a flat vertical surface such as a wall, to which it must be firmly attached. Like other structural elements, a canti ...
design and employs a Wortmann FX 63-137
airfoil. Glide path control is via
spoilers on the wing top surface. The aircraft is normally flown without a windshield, but a
Plexiglas
Poly(methyl methacrylate) (PMMA) belongs to a group of materials called engineering plastics. It is a transparent thermoplastic. PMMA is also known as acrylic, acrylic glass, as well as by the trade names and brands Crylux, Plexiglas, Acrylite ...
canopy
Canopy may refer to:
Plants
* Canopy (biology), aboveground portion of plant community or crop (including forests)
* Canopy (grape), aboveground portion of grapes
Religion and ceremonies
* Baldachin or canopy of state, typically placed over an ...
is optional. The aircraft's best
glide ratio
In aerodynamics, the lift-to-drag ratio (or L/D ratio) is the lift generated by an aerodynamic body such as an aerofoil or aircraft, divided by the aerodynamic drag caused by moving through air. It describes the aerodynamic efficiency under giv ...
is 16:1 at . With both the canopy and pilot doors fitted the best glide ratio is 18:1. The landing gear is a fixed skid and the aircraft is equipped with a
ballistic parachute
A ballistic parachute, ballistic reserve parachute, or emergency ballistic reserve parachute, is a parachute ejected from its casing by a small explosion, much like that used in an ejection seat. The advantage of the ballistic parachute over a co ...
full aircraft rescue system. The aircraft is normally transported by trailer and can be assembled in 10 minutes.
The ULF 1 was approved in West Germany in July 1980 and
Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...
in 1983.
The ULF 1 can be foot-launched from slopes of at least 15°. The pilot foot launches the aircraft suspending it on the shoulder harness and, once airborne sits on a retractable slat seat and closes two partial lower doors. It can also be launched by
bungee launch
Gliding is a recreational activity and competitive air sport in which pilots fly unpowered aircraft known as gliders or sailplanes using naturally occurring currents of rising air in the atmosphere to remain airborne. The word ''soaring'' is a ...
,
winch-launch,
auto-tow
Gliding is a recreational activity and competitive air sport in which pilots fly unpowered aircraft known as gliders or sailplanes using naturally occurring currents of rising air in the atmosphere to remain airborne. The word ''soaring'' is al ...
and
aerotow
Gliding is a recreational activity and competitive air sport in which pilots fly unpowered aircraft known as gliders or sailplanes using naturally occurring currents of rising air in the atmosphere to remain airborne. The word ''soaring'' is a ...
.
The cost of building the aircraft from plans is estimated by the designer as
€
The euro sign () is the currency sign used for the euro, the official currency of the eurozone and unilaterally adopted by Kosovo and Montenegro. The design was presented to the public by the European Commission on 12 December 1996. It consists ...
2500. In 2011 the plans cost €150 and were available in German and English. The plans consist of 31 blueprint pages and a 37-page construction manual. The manufacturer claims a build time of about 1000 hours.
Operational history
The prototype has flown more than 200 flights totalling over 150 hours, most of which were foot-launched. The longest flight flown by a ULF 1 is six hours and .
More than 40 examples have been completed and flown.
Specifications (ULF 1)
See also
References
External links
*
{{EEL aircraft
1970s German sailplanes
Sailplanes designed for foot-launching
Homebuilt aircraft
Entwicklung und Erprobung von Leichtflugzeugen aircraft
Aircraft first flown in 1977