The DFS Rhönsperber, otherwise known as the Schweyer Rhönsperber or Jacobs Rhönsperber (in English '' Rhön Sparrowhawk'') was a single seat competition glider designed in

Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...

by Hans Jacobs and first flown in 1935. For several years it was regarded as the best German sailplane and about one hundred were built.

Design and development

In 1935, Hans Jacobs was asked by

Alexander Lippisch Alexander Martin Lippisch (2 November 1894 – 11 February 1976) was a German aeronautical engineer, a pioneer of aerodynamics who made important contributions to the understanding of tailless aircraft, delta wings and the ground effect in aircra ...

to become chief designer of sailplanes at DFS (

Deutsche Forschungsanstalt Für Segelflug The , or DFS , was formed in 1933 to centralise all gliding activity in Germany, under the directorship of Professor Walter Georgii. It was formed by the nationalisation of the Rhön-Rossitten Gesellschaft (RRG) at Darmstadt.Reitsch, H., 1955, ...

) at

Darmstadt Darmstadt () is a city in the States of Germany, state of Hesse in Germany, located in the southern part of the Frankfurt Rhine Main Area, Rhine-Main-Area (Frankfurt Metropolitan Region). Darmstadt has around 160,000 inhabitants, making it the ...

, after the closure the RRG ( Rhön-Rossitten Gesellschaft) at the

Wasserkuppe The Wasserkuppe (;) is the highest mountain in the Rhön Mountains, Rhön range and the tallest elevation in the Germany, German state of Hesse, standing at above sea level. It forms a prominent plateau within the Fulda district and is known as ...

in 1933. The Rhönsperber was not unlike his earlier Rhönbussard, but was enlarged all round, with a repositioned wing and an enclosed

cockpit A cockpit or flight deck is the area, on the front part of an aircraft, spacecraft, or submersible, from which a pilot controls the vehicle. The cockpit of an aircraft contains flight instruments on an instrument panel, and the controls th ...

. With a greater

aspect ratio The aspect ratio of a geometry, geometric shape is the ratio of its sizes in different dimensions. For example, the aspect ratio of a rectangle is the ratio of its longer side to its shorter side—the ratio of width to height, when the rectangl ...

, its performance was better. For a few years after its first flight in 1935, the Rhönsperber was held to be the best German competition sailplane. The Rhönbussard had its

wing A wing is a type of fin that produces both Lift (force), lift and drag while moving through air. Wings are defined by two shape characteristics, an airfoil section and a planform (aeronautics), planform. Wing efficiency is expressed as lift-to-d ...

over the cockpit, limiting the pilot's view, but on the Rhönsperber it was lowered to mid fuselage. It is an entirely wood and

fabric Textile is an umbrella term that includes various fiber-based materials, including fibers, yarns, filaments, threads, and different types of fabric. At first, the word "textiles" only referred to woven fabrics. However, weaving is no ...

aircraft with a wing built around a single spar. Forward of the spar the wing is

plywood Plywood is a composite material manufactured from thin layers, or "plies", of wood veneer that have been stacked and glued together. It is an engineered wood from the family of manufactured boards, which include plywood, medium-density fibreboa ...

covered around the

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 ...

, forming a torsion-resisting D-box. Aft of the spar, the covering is fabric. Each wing has two sections, a parallel- chord centre section and a double straight tapered outer panel, ending with semi-elliptical tips. The only dihedral, 5°, is on the centre section, forming the gull wing. Airbrakes are centrally placed on the upper centre section surface and fabric-covered

aileron An aileron (French for "little wing" or "fin") is a hinged flight control surface usually forming part of the trailing edge of each wing of a fixed-wing aircraft. Ailerons are used in pairs to control the aircraft in roll (or movement aroun ...

s fill the

trailing edge The trailing edge of an aerodynamic surface such as a wing is its rear edge, where the airflow separated by the leading edge meets.Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', page 521. Aviation Supplies & Academics, 1997. ...

s of the outer panels. The fuselage is ply covered and of teardrop cross section, deep around the generously dimensioned cockpit. The

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 a ...

is multi-framed with a rather upright windscreen; the fixed glazing extends rearwards to mid wing and the forward section, including the screen, instruments and a small surrounding portion of the fuselage, hinges to starboard for access. The narrow

fin A fin is a thin component or appendage attached to a larger body or structure. Fins typically function as foils that produce lift or thrust, or provide the ability to steer or stabilize motion while traveling in water, air, or other fluids. F ...

is also ply covered but the rest of the

empennage The empennage ( or ), also known as the tail or tail assembly, is a structure at the rear of an aircraft that provides stability during flight, in a way similar to the feathers on an arrow.Crane, Dale: ''Dictionary of Aeronautical Terms, third ed ...

is fabric over wood framing. The

rudder A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, airship, or other vehicle that moves through a fluid medium (usually air or water). On an airplane, the rudder is used primarily to counter adverse yaw ...

, like the fin, is straight tapered with a rounded tip; it extends down to the keel. A straight tapered

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 ...

and

elevators An elevator (American English) or lift (English in the Commonwealth of Nations, Commonwealth English) is a machine that vertically transports people or freight between levels. They are typically powered by electric motors that drive tracti ...

are placed on top of the fuselage, the elevators having a cut-out for rudder movement. The Rhönsperber has no landing wheel, only a curved main skid reaching from the nose to behind mid-chord, and an integral, pronounced tail bumper. Since the DFS built only prototypes, construction of the Rhönsperber was undertaken by Flugzeugbau Schweyer at

Ludwigshafen Ludwigshafen, officially Ludwigshafen am Rhein (; meaning "Ludwig I of Bavaria, Ludwig's Port upon the Rhine"; Palatine German dialects, Palatine German: ''Ludwichshafe''), is a List of cities and towns in Germany, city in the German state of Rh ...

who produced about one hundred.

Operational history

One notable flight set, albeit briefly, a new world distance record of 474 km (296 mi). Flown by Ludwig Hofmann in 1935, this was the first glider flight over more than 400 km (250 mi). Another glider world record was set in 1937, when Paul Steinig reached an altitude of 6,200 m (18,898 ft). The first sailplane crossing of the

Alps The Alps () are some of the highest and most extensive mountain ranges in Europe, stretching approximately across eight Alpine countries (from west to east): Monaco, France, Switzerland, Italy, Liechtenstein, Germany, Austria and Slovenia. ...

was flown by Heini Dittmar in 1936. Another well-known aviator,

Ernst Udet Ernst Udet (26 April 1896 – 17 November 1941) was a German pilot during World War I and a ''Luftwaffe'' Colonel-General (''Generaloberst'') during World War II. Udet joined the Imperial German Air Service in April 1915 at the age of 19 ...

had his own Rhönsperber, which he once flew from the

Jungfraujoch The Jungfraujoch (German language, German: lit. "maiden saddle") is a Saddle (landform), saddle connecting two major Four-thousander, 4000ers of the Bernese Alps: the Jungfrau and the Mönch. It lies at an elevation of above sea level and is dir ...

in 1935. The following year Peter Riedel gave demonstrations of glider aerobatics at the

Winter Olympics The Winter Olympic Games (), also known as the Winter Olympics, is a major international multi-sport event held once every four years for sports practiced on snow and ice. The first Winter Olympic Games, the 1924 Winter Olympics, were held i ...

, taking off and landing on ice.

Hanna Reitsch Hanna Reitsch (29 March 1912 – 24 August 1979) was a German Pilot (aeronautics), aviator and test pilot. Along with Melitta von Stauffenberg, she flight-tested many of Germany's new aircraft during World War II and received many hono ...

also put a Rhönsperber through some vigorous aerobatics, reaching 385 km/h (240 mph) in a dive and losing 1,920 m (6,300 ft) in a forty-two turn, 165 second spin. There were many competition successes. The type was marketed in the U.S. by Emil Lehecka, who imported one for his participation in the US Annual National Soaring Contest in 1937. A single Rhönsperber (civilian registration NC17898) was impressed into

USAAF The United States Army Air Forces (USAAF or AAF) was the major land-based aerial warfare service component of the United States Army and ''de facto'' aerial warfare service branch of the United States during and immediately after World War II ...

service under the designation TG-19 ( s/n 42-57165). A Rhönsperber (''BGA260''), flying with a Rhönbussard empennage which has a more angular horizontal tail, is still active in the U.K. as of 2018. It is based at the London Gliding Club, Dunstable, and is regularly flown on vintage glider days. A "perfect" Rhönsperber replica, built by Otto Grau in 1997, remained on the German civil aircraft register in 2010.

Aircraft on display

* Muzeum Lotnictwa Polskiego,

Kraków , officially the Royal Capital City of Kraków, is the List of cities and towns in Poland, second-largest and one of the oldest cities in Poland. Situated on the Vistula River in Lesser Poland Voivodeship, the city has a population of 804,237 ...

: Rhönsperber ''SP-148''

Specifications

References

External links