Hans Multhopp
Encyclopedia
Hans Multhopp was a German
aeronautical engineer/designer
. Receiving a degree from the University of Göttingen, Multhopp worked with the famous designer Kurt Tank
at the Focke-Wulf Flugzeugbau AG
during World War II
, and was the leader of the team responsible for the design of the Focke-Wulf Ta 183
lightweight jet fighter, which was the winner of the 1945 Emergency Fighter Competition. Emigrating to the United Kingdom
after the war, he assisted in the advancement of British aeronautic science before moving to the United States
, where his work for Martin Marietta
on lifting bodies
provided aerodynamic experience that proved instrumental in the development of the Space Shuttle
.
, before transferring to the University of Göttingen in 1934. Studying there under the guidance of the famed aerodynamicist Ludwig Prandtl, who regarded him as his best student, Multhopp assisted in the design and construction of several gliders
while working on a thesis on the subject of wing aerodynamics. During his time at the university, he also participated in experiments under the aegis of the Aerodynamische Versuchsanstalt (AVA), the German counterpart to the American National Advisory Committee for Aeronautics
. In 1937, Multhopp was placed in charge of one of AVA's wind tunnels. More importantly he had already published a seminal paper on wing-lift theory and before he had fulfilled his doctoral requirements, his work had attracted the interest of other German aviation concerns. Consequently, Multhopp was approached by Kurt Tank in 1938, who offered him employment at Focke-Wulf.
and dive brake
apparatus, which was installed on the unsuccessful Focke-Wulf Fw 191
. During flight testing of the Fw 191, when deployed, the Multhopp-Klappe caused severe flutter.
In 1944, in collaboration with Tank and his design team, Multhopp was assigned to a research project to meet and exceed the specifications of the Reichsluftfahrtministerium (RLM)'s Emergency Fighter Competition for a single-seat jet-powered fighter intended for performance at high-altitude. His design of the diminutive Ta 183 Huckebein (German: Hunchback), distinguished by a 40˚ swept-wing and T-tail (characterized as the "Multhopp T-tail") was the winner of the Luftwaffe's 1945 Emergency Fighter Program. However, due to the deteriorating war situation, delays in development meant that only wind tunnel models had been completed by the time of Germany's surrender.
Although David Myhra among other historians claim that the post-war Soviet MiG-15 was based on the Ta 183, modern experts in Russian and Soviet aviation history such as Yefim Gordon reject this, although acknowledging that some of the captured data from Multhopp's design work was examined by Artem Mikoyan and Mikhail Gurevich
in the formative study of contemporary research. The swept-wing data that was amassed at Focke Wulf was, however, utilized by the Saab design office in its preliminary work that led to the Saab J29 fighter. A member of the Saab engineering team had been allowed to review German aeronautical documents stored in Switzerland. These files captured by the Americans in 1945 clearly indicated delta and swept-wing designs had the effect of "reducing drag dramatically as the aircraft approached the sound barrier." Although more sophisticated than the Ta 183, the Saab J 29 has more than a superficial link to the earlier German fighter project.
Post-war, Tank and most of his team left Germany to go to work in Argentina, where the Ta 183 would be developed into the FMA IAe 33 Pulqui II
. Beginning in 1947, 62 of the technical staff along with a small group of test pilots followed Tank to reestablish themselves at the Fábrica Militar de Aviones at Córdoba. Multhopp was the only prominent engineer of the team who did not follow Tank, however, desiring to "move out of the shadow" of his mentor. Instead, Multhopp had chosen to emigrate to the United Kingdom in 1945, where he was quickly employed by the Royal Aircraft Establishment
(RAE) at Farnborough
. Aerodynamicist Martin Winter, Multhopp's assistant at Focke Wulf, accompanied his former team leader to RAE Farnborough.
. The salient features included jettisonable wheels (landing was achieved with a retractable skid landing gear), a prone pilot position in the nose with the cockpit enclosure centered in the nose (four windows framed the circular intake), a T-tail and mid-mounted swept-wing, swept at 40˚. The RAE supersonic research vehicle designed in 1947–1948 and intended for speeds up Mach
1.24 at 36,000 ft, may have inspired parts of the design of "Teddy" Petter's Lightning
fighter. The RAE project was not funded and remained a moribund "paper project." In addition, Multhopp also developed a theory for calculating the lift distribution of wings at subsonic speeds.
In 1949, the Glenn L. Martin Company
(later Martin Marietta
) of Essex, Maryland
made efforts to recruit Multhopp to their staff of aeronautical engineers. These efforts proved successful, and he left his position at Farnborough to emigrate to the United States.
At Martin, he assisted in the design of the XB-51
medium bomber, the design of which reflected his work in swept wing
design and T-tail
aerodynamics, and by 1963, he had been promoted to the position of chief scientist at Martin. In this position, as part of a U.S. Air Force contract for the development of a full-scale model of a high-volume lifting body design for manned spaceflight, he developed the "SV-5" aircraft.
The SV-5, the centerpiece of the START (Spacecraft Technology and Advanced Reentry Tests) project, was promoted by Multhopp as superior to NASA's M2
and HL-10
lifting body shapes, having a better lift-to-drag ratio and greater re-entry cross-range capability, along with better aerodynamics and improved design efficiency.
Developed into the X-24, Multhopp's design proved successful, and provided valuable flight test information that assisted the design of NASA
's Space Shuttle
. Multhopp himself, however, faded from public view in the mid- to late-1960s. However, he continued to be active in aeronautical design, a 1966 paper challenging the view that tactical aircraft necessarily required greater and greater speed to be effective, and proposing a close air support
aircraft armed with a heavy gun for anti-tank operations to Martin management, which was not pursued.
in which pieces cannot move backwards until they have reached the far side of the board (another game by the same name was proposed by V.R. Parton).
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
aeronautical engineer/designer
Aerospace engineering
Aerospace engineering is the primary branch of engineering concerned with the design, construction and science of aircraft and spacecraft. It is divided into two major and overlapping branches: aeronautical engineering and astronautical engineering...
. Receiving a degree from the University of Göttingen, Multhopp worked with the famous designer Kurt Tank
Kurt Tank
Kurt Waldemar Tank was a German aeronautical engineer and test pilot, heading the design department at Focke-Wulf from 1931-45. He designed several important aircraft of World War II, including the Focke-Wulf Fw 190 fighter aircraft.-Early life:Tank was born in Bromberg , Province of Posen...
at the Focke-Wulf Flugzeugbau AG
Focke-Wulf
Focke-Wulf Flugzeugbau AG was a German manufacturer of civil and military aircraft before and during World War II. Many of the company's successful fighter aircraft designs were slight modifications of the Focke-Wulf Fw 190.-History:...
during World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
, and was the leader of the team responsible for the design of the Focke-Wulf Ta 183
Focke-Wulf Ta 183
The Focke-Wulf Ta 183 Huckebein was a design for a jet-powered fighter aircraft intended as the successor to the Messerschmitt Me 262 and other day fighters in Luftwaffe service during World War II. It was developed only to the extent of wind tunnel models when the war ended, but the basic design...
lightweight jet fighter, which was the winner of the 1945 Emergency Fighter Competition. Emigrating to the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
after the war, he assisted in the advancement of British aeronautic science before moving to the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
, where his work for Martin Marietta
Martin Marietta
Martin Marietta Corporation was an American company founded in 1961 through the merger of The Martin Company and American-Marietta Corporation. The combined company became a leader in chemicals, aerospace, and electronics. In 1995, it merged with Lockheed Corporation to form Lockheed Martin. The...
on lifting bodies
Lifting body
A lifting body is a fixed-wing aircraft configuration in which the body itself produces lift. In contrast to a flying wing, which is a wing with minimal or no conventional fuselage, a lifting body can be thought of as a fuselage with little or no conventional wing...
provided aerodynamic experience that proved instrumental in the development of the Space Shuttle
Space Shuttle
The Space Shuttle was a manned orbital rocket and spacecraft system operated by NASA on 135 missions from 1981 to 2011. The system combined rocket launch, orbital spacecraft, and re-entry spaceplane with modular add-ons...
.
Early life
Born in 1913, Multhopp studied at the Technische Hochschule in HannoverHanover
Hanover or Hannover, on the river Leine, is the capital of the federal state of Lower Saxony , Germany and was once by personal union the family seat of the Hanoverian Kings of Great Britain, under their title as the dukes of Brunswick-Lüneburg...
, before transferring to the University of Göttingen in 1934. Studying there under the guidance of the famed aerodynamicist Ludwig Prandtl, who regarded him as his best student, Multhopp assisted in the design and construction of several gliders
Glider aircraft
Glider aircraft are heavier-than-air craft that are supported in flight by the dynamic reaction of the air against their lifting surfaces, and whose free flight does not depend on an engine. Mostly these types of aircraft are intended for routine operation without engines, though engine failure can...
while working on a thesis on the subject of wing aerodynamics. During his time at the university, he also participated in experiments under the aegis of the Aerodynamische Versuchsanstalt (AVA), the German counterpart to the American National Advisory Committee for Aeronautics
National Advisory Committee for Aeronautics
The National Advisory Committee for Aeronautics was a U.S. 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 and personnel transferred to the newly created National Aeronautics and...
. In 1937, Multhopp was placed in charge of one of AVA's wind tunnels. More importantly he had already published a seminal paper on wing-lift theory and before he had fulfilled his doctoral requirements, his work had attracted the interest of other German aviation concerns. Consequently, Multhopp was approached by Kurt Tank in 1938, who offered him employment at Focke-Wulf.
World War II
At Focke-Wulf, Multhopp was promoted to assistant in charge of the aerodynamics department in 1940, then was promoted to advanced design bureau chief in 1943. One of his innovative projects during this time was the Multhopp-Klappe, a combined flapFlap (aircraft)
Flaps are normally hinged surfaces mounted on the trailing edges of the wings of a fixed-wing aircraft to reduce the speed an aircraft can be safely flown at and to increase the angle of descent for landing without increasing air speed. They shorten takeoff and landing distances as well as...
and dive brake
Dive brake
Dive brakes or dive flaps are deployed to slow down an aircraft when in a dive. They usually consist of a metal flap that is raised against the air flow, thus creating drag and reducing dive speed....
apparatus, which was installed on the unsuccessful Focke-Wulf Fw 191
Focke-Wulf Fw 191
The Focke-Wulf Fw 191 was a prototype German bomber of World War II. Two versions were intended to be produced, a twin-engine version using the Junkers Jumo 222 engine and a four-engine variant which was to have used the smaller Daimler-Benz DB 605 engine...
. During flight testing of the Fw 191, when deployed, the Multhopp-Klappe caused severe flutter.
In 1944, in collaboration with Tank and his design team, Multhopp was assigned to a research project to meet and exceed the specifications of the Reichsluftfahrtministerium (RLM)'s Emergency Fighter Competition for a single-seat jet-powered fighter intended for performance at high-altitude. His design of the diminutive Ta 183 Huckebein (German: Hunchback), distinguished by a 40˚ swept-wing and T-tail (characterized as the "Multhopp T-tail") was the winner of the Luftwaffe's 1945 Emergency Fighter Program. However, due to the deteriorating war situation, delays in development meant that only wind tunnel models had been completed by the time of Germany's surrender.
Mikhail Gurevich
Mikhail Iosifovich Gurevich was a Soviet aircraft designer, a partner of the famous MiG military aviation bureau. He was of Ukrainian Jewish Heritage....
in the formative study of contemporary research. The swept-wing data that was amassed at Focke Wulf was, however, utilized by the Saab design office in its preliminary work that led to the Saab J29 fighter. A member of the Saab engineering team had been allowed to review German aeronautical documents stored in Switzerland. These files captured by the Americans in 1945 clearly indicated delta and swept-wing designs had the effect of "reducing drag dramatically as the aircraft approached the sound barrier." Although more sophisticated than the Ta 183, the Saab J 29 has more than a superficial link to the earlier German fighter project.
Post-war, Tank and most of his team left Germany to go to work in Argentina, where the Ta 183 would be developed into the FMA IAe 33 Pulqui II
FMA IAe 33 Pulqui II
The FMA IAe 33 Pulqui II was a jet fighter aircraft designed by Kurt Tank in the late 1940s in Argentina, under the Perón government, and built by the Fábrica Militar de Aviones...
. Beginning in 1947, 62 of the technical staff along with a small group of test pilots followed Tank to reestablish themselves at the Fábrica Militar de Aviones at Córdoba. Multhopp was the only prominent engineer of the team who did not follow Tank, however, desiring to "move out of the shadow" of his mentor. Instead, Multhopp had chosen to emigrate to the United Kingdom in 1945, where he was quickly employed by the Royal Aircraft Establishment
Royal Aircraft Establishment
The Royal Aircraft Establishment , was a British research establishment, known by several different names during its history, that eventually came under the aegis of the UK Ministry of Defence , before finally losing its identity in mergers with other institutions.The first site was at Farnborough...
(RAE) at Farnborough
Farnborough Airfield
Farnborough Airport or TAG London Farnborough Airport is an airport situated in Farnborough, Rushmoor, Hampshire, England...
. Aerodynamicist Martin Winter, Multhopp's assistant at Focke Wulf, accompanied his former team leader to RAE Farnborough.
Post-war
During four years spent working at Farnborough, Multhopp and Winter's studies of swept-wing planforms resulted in the design of a unique high-speed research aircraft to be powered by the Rolls-Royce AJ65 AvonRolls-Royce Avon
|-See also:-Bibliography:* Gunston, Bill. World Encyclopaedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN 1-85260-163-9-External links:**** a 1955 Flight article on the development of the Avon...
. The salient features included jettisonable wheels (landing was achieved with a retractable skid landing gear), a prone pilot position in the nose with the cockpit enclosure centered in the nose (four windows framed the circular intake), a T-tail and mid-mounted swept-wing, swept at 40˚. The RAE supersonic research vehicle designed in 1947–1948 and intended for speeds up Mach
Mach number
Mach number is the speed of an object moving through air, or any other fluid substance, divided by the speed of sound as it is in that substance for its particular physical conditions, including those of temperature and pressure...
1.24 at 36,000 ft, may have inspired parts of the design of "Teddy" Petter's Lightning
English Electric Lightning
The English Electric Lightning is a supersonic jet fighter aircraft of the Cold War era, noted for its great speed and unpainted natural metal exterior finish. It is the only all-British Mach 2 fighter aircraft. The aircraft was renowned for its capabilities as an interceptor; Royal Air Force ...
fighter. The RAE project was not funded and remained a moribund "paper project." In addition, Multhopp also developed a theory for calculating the lift distribution of wings at subsonic speeds.
Glenn L. Martin Company
The Glenn L. Martin Company was an American aircraft and aerospace manufacturing company that was founded by the aviation pioneer Glenn L. Martin. The Martin Company produced many important aircraft for the defense of the United States and its allies, especially during World War II and the Cold War...
(later Martin Marietta
Martin Marietta
Martin Marietta Corporation was an American company founded in 1961 through the merger of The Martin Company and American-Marietta Corporation. The combined company became a leader in chemicals, aerospace, and electronics. In 1995, it merged with Lockheed Corporation to form Lockheed Martin. The...
) of Essex, Maryland
Essex, Maryland
-Demographics:As of the census of 2000, there were 39,078 people, 15,952 households, and 10,336 families residing in the CDP. The population density was 4,104.1 people per square mile . There were 16,997 housing units at an average density of 1,785.1 per square mile...
made efforts to recruit Multhopp to their staff of aeronautical engineers. These efforts proved successful, and he left his position at Farnborough to emigrate to the United States.
At Martin, he assisted in the design of the XB-51
Martin XB-51
|-See also:-References:NotesBibliography* Andrade, John M. U.S. Military Aircraft Designations and Serials since 1909. Earl Shilton, Leicester, UK: Midland Counties Publications, 1979. ISBN 0-904597-22-9....
medium bomber, the design of which reflected his work in swept wing
Swept wing
A swept wing is a wing planform favored for high subsonic jet speeds first investigated by Germany during the Second World War. Since the introduction of the MiG-15 and North American F-86 which demonstrated a decisive superiority over the slower first generation of straight-wing jet fighters...
design and T-tail
T-tail
thumb|right|Grob motor gliderA T-tail is an aircraft tail stabilizer configuration in which the horizontal surfaces are mounted to the top of the vertical stabilizer. Traditionally, the horizontal control surfaces are mounted to the fuselage at the base of the vertical stabilizer...
aerodynamics, and by 1963, he had been promoted to the position of chief scientist at Martin. In this position, as part of a U.S. Air Force contract for the development of a full-scale model of a high-volume lifting body design for manned spaceflight, he developed the "SV-5" aircraft.
The SV-5, the centerpiece of the START (Spacecraft Technology and Advanced Reentry Tests) project, was promoted by Multhopp as superior to NASA's M2
Northrop M2-F3
The Northrop M2-F3 was a heavyweight lifting body rebuilt from the Northrop M2-F2 after it crashed at the Dryden Flight Research Center in 1967. It was modified with an additional third vertical fin - centered between the tip fins - to improve control characteristics...
and HL-10
Northrop HL-10
The Northrop HL-10 was one of five heavyweight lifting body designs flown at NASA's Flight Research Center , Edwards, California, from July 1966 to November 1975 to study and validate the concept of safely maneuvering and landing a low lift-over-drag vehicle designed for reentry from space...
lifting body shapes, having a better lift-to-drag ratio and greater re-entry cross-range capability, along with better aerodynamics and improved design efficiency.
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
's Space Shuttle
Space Shuttle
The Space Shuttle was a manned orbital rocket and spacecraft system operated by NASA on 135 missions from 1981 to 2011. The system combined rocket launch, orbital spacecraft, and re-entry spaceplane with modular add-ons...
. Multhopp himself, however, faded from public view in the mid- to late-1960s. However, he continued to be active in aeronautical design, a 1966 paper challenging the view that tactical aircraft necessarily required greater and greater speed to be effective, and proposing a close air support
Close air support
In military tactics, close air support is defined as air action by fixed or rotary winged aircraft against hostile targets that are close to friendly forces, and which requires detailed integration of each air mission with fire and movement of these forces.The determining factor for CAS is...
aircraft armed with a heavy gun for anti-tank operations to Martin management, which was not pursued.
Influence on chess
In 1974, Multhopp's son, also named Hans, invented "Checkers chess", a chess variantChess variant
A chess variant is a game related to, derived from or inspired by chess. The difference from chess might include one or more of the following:...
in which pieces cannot move backwards until they have reached the far side of the board (another game by the same name was proposed by V.R. Parton).