Silverbird (aircraft) - AbsoluteAstronomy.com

Silbervogel, German

German language

German is a West Germanic language, related to and classified alongside English and Dutch. With an estimated 90 – 98 million native speakers, German is one of the world's major languages and is the most widely-spoken first language in the European Union....

for silver bird, was a design for a rocket

Rocket

A rocket is a missile, spacecraft, aircraft or other vehicle which obtains thrust from a rocket engine. In all rockets, the exhaust is formed entirely from propellants carried within the rocket before use. Rocket engines work by action and reaction...

-powered sub-orbital bomber aircraft produced by Eugen Sänger

Eugen Sänger

Eugen Sänger was an Austrian-German aerospace engineer best known for his contributions to lifting body and ramjet technology.-Early career:...

and Irene Bredt

Irene Bredt

Irene Bredt was a German engineer, mathematician and physicist. She is co-credited with the design of a proposed intercontinental spaceplane/bomber prior to and during World War II....

in the late 1930s for The Third Reich/Nazi Germany. It is also known as the RaBo (Raketenbomber or "rocket bomber"). It was one of a number of designs considered for the Amerika Bomber
Amerika Bomber
The Amerika-Bomber project was an initiative of the Reichsluftfahrtministerium, the Nazi Germany Air Ministry, to obtain a long-range strategic bomber for the Luftwaffe that would be capable of striking the continental United States from Germany, a range of about 5,800 km...

mission. When Walter Dornberger

Walter Dornberger

Major-General Dr Walter Robert Dornberger was a German Army artillery officer whose career spanned World Wars I and II. He was a leader of Germany's V-2 rocket program and other projects at the Peenemünde Army Research Center....

attempted to create interest in military spaceplane

Spaceplane

A spaceplane is a vehicle that operates as an aircraft in Earth's atmosphere, as well as a spacecraft when it is in space. It combines features of an aircraft and a spacecraft, which can be thought of as an aircraft that can endure and maneuver in the vacuum of space or likewise a spacecraft that...

s in the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

after 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...

, he chose the more diplomatic term antipodal bomber.

Concept

The design was a significant one, as it incorporated new rocket technology, and the principle of the lifting body

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...

, forshadowing future development of winged spacecraft such as the X-20 Dyna-Soar

X-20 Dyna-Soar

The X-20 Dyna-Soar was a United States Air Force program to develop a spaceplane that could be used for a variety of military missions, including reconnaissance, bombing, space rescue, satellite maintenance, and sabotage of enemy satellites...

of the 1960s and 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...

of the 1970s. In the end, it was considered too complex and expensive to produce. The design never went beyond mock up test.

The Silbervogel was intended to fly long distances in a series of short hops. The aircraft was to have begun its mission propelled along a 3 km (2 mi) long rail track by a large rocket-powered sled to about 1930 km/h (1,199.2 mph). Once airborne, it was to fire its own rocket engine and continue to climb to an altitude of 145 km (90.1 mi), at which point it would be travelling at some 22100 km/h (13,732.3 mph). It would then gradually descend into the stratosphere

Stratosphere

The stratosphere is the second major layer of Earth's atmosphere, just above the troposphere, and below the mesosphere. It is stratified in temperature, with warmer layers higher up and cooler layers farther down. This is in contrast to the troposphere near the Earth's surface, which is cooler...

, where the increasing air density would generate lift

Lift (force)

A fluid flowing past the surface of a body exerts a surface force on it. Lift is the component of this force that is perpendicular to the oncoming flow direction. It contrasts with the drag force, which is the component of the surface force parallel to the flow direction...

against the flat underside of the aircraft, eventually causing it to "bounce" and gain altitude again, where this pattern would be repeated. Because of drag

Drag (physics)

In fluid dynamics, drag refers to forces which act on a solid object in the direction of the relative fluid flow velocity...

, each bounce would be shallower than the preceding one, but it was still calculated that the Silbervogel would be able to cross the Atlantic, deliver a 4000 kg (8,818.5 lb) bomb to the continental US, and then continue its flight to a landing site somewhere in the Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

ese held Pacific, a total journey of 19000 kilometre.

Postwar analysis of the Silbervogel design involving a mathematical control analysis unearthed a computational error and it turned out that the heat flow during the initial re-entry would have been far higher than originally calculated by Sänger and Bredt; if the Silbervogel had been constructed according to their flawed calculations the craft would have been destroyed during re-entry. The problem could have been solved by augmenting the heat shield, but this would have reduced the craft's already small payload capacity.

History

On 3 December 1941 Sänger sent his initial proposal for a suborbital glider to the Reich Air Ministry (RLM) as Geheime Kommandosache Nr. 4268/LXXX5. The 900-page proposal was regarded with disfavor at the RLM due to its size and complexity and was filed away.

Professor Walter Gregorii had Sänger rework his report and a greatly reduced version was submitted to the RLM in September 1944, as UM 3538. It was the first serious proposal for a vehicle which could carry a pilot and payload to the lower edge of space.

Two manned and one unmanned version were proposed: the Antipodenferngleiter (antipodal long-range glider) and the Interglobalferngleiter (intercontinental long-range glider). Both were to be launched from a rocket-powered sled. The two manned versions were identical except in payload. The Antipodenferngleiter was to be launched at a very steep angle (which would shorten the range) and after dropping its bomb load on New York City was to land at a Japanese base in the Pacific.

Postwar

After the war ended, Sänger and Bredt worked for the French government

Government of France

The government of the French Republic is a semi-presidential system determined by the French Constitution of the fifth Republic. The nation declares itself to be an "indivisible, secular, democratic, and social Republic"...

and in 1949 founded the Fédération Astronautique. Whilst in France, Sänger was the subject of a botched attempt by Soviet agent

NKVD

The People's Commissariat for Internal Affairs was the public and secret police organization of the Soviet Union that directly executed the rule of power of the Soviets, including political repression, during the era of Joseph Stalin....

s to win him over. Joseph Stalin

Joseph Stalin

Joseph Vissarionovich Stalin was the Premier of the Soviet Union from 6 May 1941 to 5 March 1953. He was among the Bolshevik revolutionaries who brought about the October Revolution and had held the position of first General Secretary of the Communist Party of the Soviet Union's Central Committee...

had become intrigued by reports of the Silbervogel design and sent his son, Vasily

Vasily Dzhugashvili

Vasily Iosifovich Dzhugashvili , known also as Vasily Stalin , , was the son of Joseph Stalin and his second wife, Nadezhda Alliluyeva....

, and scientist Grigori Tokaty

Grigori Tokaty

Dr Grigori Tokaty was a rocket scientist and long-standing critic of Stalin's USSR. During World War II he served as Head of Aeronautics Laboratory, Zhukovsky Academy 1938-41...

to kidnap Sänger and Bredt and bring them to the USSR

Soviet Union

The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....

. When this plan failed, a new design bureau was set up by Mstislav Vsevolodovich Keldysh

Mstislav Keldysh

Mstislav Vsevolodovich Keldysh was a Soviet scientist in the field of mathematics and mechanics, academician of the USSR Academy of Sciences , President of the USSR Academy of Sciences , three times Hero of Socialist Labor , fellow of the Royal Society of Edinburgh . He was one of the key figures...

in 1946 to research the idea. A new version powered by ramjet

Ramjet

A ramjet, sometimes referred to as a stovepipe jet, or an athodyd, is a form of airbreathing jet engine using the engine's forward motion to compress incoming air, without a rotary compressor. Ramjets cannot produce thrust at zero airspeed and thus cannot move an aircraft from a standstill...

s instead of a rocket engine was developed, usually known as the Keldysh bomber

Keldysh bomber

The Keldysh bomber was a Soviet design for a rocket-powered sub-orbital bomber aircraft which drew heavily upon work carried out by Eugen Sänger and Irene Bredt for the German Silbervogel project.- Development :...

, but not produced. The design, however, formed the basis for a number of additional cruise missile

Cruise missile

A cruise missile is a guided missile that carries an explosive payload and is propelled, usually by a jet engine, towards a land-based or sea-based target. Cruise missiles are designed to deliver a large warhead over long distances with high accuracy...

designs right into the early 1960s, none of which were ever produced.

In the US, a similar project, the X-20 Dyna-Soar

X-20 Dyna-Soar

, was to be launched on a Titan II

Titan (rocket family)

Titan was a family of U.S. expendable rockets used between 1959 and 2005. A total of 368 rockets of this family were launched, including all the Project Gemini manned flights of the mid-1960s...

booster. As the manned space role moved to NASA

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...

and unmanned reconnaissance satellites were thought to be capable of all required missions, the United States Air Force gradually withdrew from manned space flight and Dyna-Soar was cancelled.

One lasting legacy of the Silverbird design is the "Regenerative cooling-regenerative engine" design, in which fuel or oxidizer is run in tubes around the engine bell in order to both cool the bell

Nozzle

A nozzle is a device designed to control the direction or characteristics of a fluid flow as it exits an enclosed chamber or pipe via an orifice....

and pressurize the fluid. Almost all modern rocket engines use this design today and some sources still refer to it as the Sänger-Bredt design.

Sanger II Space Plane

On 18 October 1985 Messerschmidt-Boelkow-Bloehm (MBB) began renewed studies of the Saenger spaceplane, this time a "piggyback" two-stage-to-orbit horizontal takeoff concept.

Concept

History

Postwar

Sanger II Space Plane

External links

See also