OTRAG
Encyclopedia
OTRAG was a German
company based in Stuttgart
, which planned in the late 1970s and early 1980s to develop an alternative propulsion
system for rocket
s. OTRAG was the first commercial developer and producer of space launch vehicle
s. The OTRAG Rocket
represents an inexpensive alternative to existing launch systems through mass-production of Common Rocket Propulsion Units (CRPU).
launch vehicle
.
The OTRAG rocket was intended to be an inexpensive alternative to the European rocket Ariane
and the NASA
space shuttle
. Kayser and a private consortium of six hundred European investors financed the development and production of the OTRAG satellite launch vehicle. Dr.Ing Kurt H. Debus
served as Chairman of the Board of OTRAG after his retirement as director of NASA
's Kennedy Space Center
, and Dr. Wernher von Braun
served as scientific adviser to Kayser.
In the face of doubts by Debus and von Braun, Kayser chose in 1975 to set up testing and launch facilities in Shaba, Zaire
(now Katanga Province
in the Democratic Republic of the Congo
). Debus and von Braun were concerned about the possibility of Zairian acquisition of missile
technology from the facilities. Kayser decided to proceed despite their opposition, and testing began at the site in 1977.
Political pressure to halt the company's operations mounted quickly. France
and the Soviet Union
were historically opposed to German long-distance rocket development, and pressured the Congolese
government into closing down the development facility in 1979. Immediately afterwards, Presidents Giscard d'Estaing of France and Leonid Brezhnev
of the Soviet Union convinced the West German government to cancel the OTRAG project and close down its German operations. In 1980, OTRAG moved its production and testing facilities to a desert site in Libya
. A series of successful tests were conducted at this site beginning in 1981.
, into a geostationary orbit
. It was planned to later increase the capacity to ten tons or more using multiple identical modules.
The rocket was to consist of individual pipes, each 27 cm in diameter and six meters long. Four of these pipes would be installed one above the other resulting in a 24 meter long fuel and oxidizer tank with a rocket engine at the lower end. The fuel was intended to be kerosene
with a 50/50 mixture of nitric acid
and dinitrogen tetroxide
as an oxidiser. Ignition was provided by a small quantity of furfuryl alcohol
injected before the fuel, which ignites hypergolically (immediately and energetically) upon contact with the nitric acid. To simplify the design, pumps were not used to move the fuel to the engines, instead the fuel tanks were only 66% filled, with compressed air in the remaining space to press propellants into the ablatively
cooled combustion chamber. Thrust control is by partially closing the electromechanical propellant valves. Pitch and yaw control can thus be achieved by differential throttling. In principle this is extremely reliable and cheap in mass production.
The modular design was intended to result in a large cost reduction due to economies of scale
. The CRPU-based satellite launching rocket was estimated to cost approximately one tenth of conventional designs. Automated production processes for all components would reduce labor cost from 20% to 80% and remove the justification for reusability of spent stages.
and Libya
. 6,000 static rocket engine tests and 16 single stage qualification tests were made to prove the concept as feasible.
The German minister of foreign affairs at that time, Hans Dietrich Genscher, is said to have finally stopped the project under pressure from France and the Soviet Union, and West Germany joined the co-financed "European rocket" Ariane project, which made the OTRAG project unnecessary and eliminated political entanglements of a still divided Germany in the early 1980s.
NASA Commercial Orbital Transportation Services
announcement stipulates a 50% US National ownership in vendor companies like von Braun Debus Kayser Rocket Science LLC, DE (BDKRS). This would force Kayser, a German citizen, to sell at least 50% of his shares to Americans.
More recently, the company has been advising Interorbital Systems
, resulting in a similar modular rocket design for their Neptune series.
John Carmack, founder and lead engineer of Armadillo Aerospace
has stated in his monthly reports and in forum posts that he expects his path to an orbital vehicle to include modular rockets similar to OTRAG technology. Kayser, being the founding engineer of OTRAG, visited Armadillo in May, 2006 and loaned Carmack some of their original research hardware.
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...
company based in Stuttgart
Stuttgart
Stuttgart is the capital of the state of Baden-Württemberg in southern Germany. The sixth-largest city in Germany, Stuttgart has a population of 600,038 while the metropolitan area has a population of 5.3 million ....
, which planned in the late 1970s and early 1980s to develop an alternative propulsion
Spacecraft propulsion
Spacecraft propulsion is any method used to accelerate spacecraft and artificial satellites. There are many different methods. Each method has drawbacks and advantages, and spacecraft propulsion is an active area of research. However, most spacecraft today are propelled by forcing a gas from the...
system for 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...
s. OTRAG was the first commercial developer and producer of space launch vehicle
Launch vehicle
In spaceflight, a launch vehicle or carrier rocket is a rocket used to carry a payload from the Earth's surface into outer space. A launch system includes the launch vehicle, the launch pad and other infrastructure....
s. The OTRAG Rocket
OTRAG Rocket
The OTRAG rocket was a modular satellite-delivery rocket developed by the OTRAG company in the 1970s and 80s. The OTRAG rocket was to become a rocket built up from several mass-produced units, intended to carry satellites with a weight of 1-10 tons or more into orbit...
represents an inexpensive alternative to existing launch systems through mass-production of Common Rocket Propulsion Units (CRPU).
History
OTRAG was founded in 1975 by the German aerospace engineer Lutz Kayser. Its goal was to develop, produce, and operate a radically different, low cost, satelliteSatellite
In the context of spaceflight, a satellite is an object which has been placed into orbit by human endeavour. Such objects are sometimes called artificial satellites to distinguish them from natural satellites such as the Moon....
launch vehicle
Launch vehicle
In spaceflight, a launch vehicle or carrier rocket is a rocket used to carry a payload from the Earth's surface into outer space. A launch system includes the launch vehicle, the launch pad and other infrastructure....
.
The OTRAG rocket was intended to be an inexpensive alternative to the European rocket Ariane
Ariane (rocket)
Ariane is a series of a European civilian expendable launch vehicles for space launch use. The name comes from the French spelling of the mythological character Ariadne....
and the 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...
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...
. Kayser and a private consortium of six hundred European investors financed the development and production of the OTRAG satellite launch vehicle. Dr.Ing Kurt H. Debus
Kurt H. Debus
Kurt Heinrich Debus was a German V-2 rocket scientist during World War II who, after being brought to the United States under Operation Paperclip, became the first director of NASA's Kennedy Space Center in 1962. Debus' U.S...
served as Chairman of the Board of OTRAG after his retirement as director of 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...
's Kennedy Space Center
Kennedy Space Center
The John F. Kennedy Space Center is the NASA installation that has been the launch site for every United States human space flight since 1968. Although such flights are currently on hiatus, KSC continues to manage and operate unmanned rocket launch facilities for America's civilian space program...
, and Dr. Wernher von Braun
Wernher von Braun
Wernher Magnus Maximilian, Freiherr von Braun was a German rocket scientist, aerospace engineer, space architect, and one of the leading figures in the development of rocket technology in Nazi Germany during World War II and in the United States after that.A former member of the Nazi party,...
served as scientific adviser to Kayser.
In the face of doubts by Debus and von Braun, Kayser chose in 1975 to set up testing and launch facilities in Shaba, Zaire
Zaire
The Republic of Zaire was the name of the present Democratic Republic of the Congo between 27 October 1971 and 17 May 1997. The name of Zaire derives from the , itself an adaptation of the Kongo word nzere or nzadi, or "the river that swallows all rivers".-Self-proclaimed Father of the Nation:In...
(now Katanga Province
Katanga Province
Katanga Province is one of the provinces of the Democratic Republic of the Congo. Between 1971 and 1997, its official name was Shaba Province. Under the new constitution, the province was to be replaced by four smaller provinces by February 2009; this did not actually take place.Katanga's regional...
in the Democratic Republic of the Congo
Democratic Republic of the Congo
The Democratic Republic of the Congo is a state located in Central Africa. It is the second largest country in Africa by area and the eleventh largest in the world...
). Debus and von Braun were concerned about the possibility of Zairian acquisition of missile
Missile
Though a missile may be any thrown or launched object, it colloquially almost always refers to a self-propelled guided weapon system.-Etymology:The word missile comes from the Latin verb mittere, meaning "to send"...
technology from the facilities. Kayser decided to proceed despite their opposition, and testing began at the site in 1977.
Political pressure to halt the company's operations mounted quickly. France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
and the Soviet Union
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....
were historically opposed to German long-distance rocket development, and pressured the Congolese
Zaire
The Republic of Zaire was the name of the present Democratic Republic of the Congo between 27 October 1971 and 17 May 1997. The name of Zaire derives from the , itself an adaptation of the Kongo word nzere or nzadi, or "the river that swallows all rivers".-Self-proclaimed Father of the Nation:In...
government into closing down the development facility in 1979. Immediately afterwards, Presidents Giscard d'Estaing of France and Leonid Brezhnev
Leonid Brezhnev
Leonid Ilyich Brezhnev – 10 November 1982) was the General Secretary of the Central Committee of the Communist Party of the Soviet Union , presiding over the country from 1964 until his death in 1982. His eighteen-year term as General Secretary was second only to that of Joseph Stalin in...
of the Soviet Union convinced the West German government to cancel the OTRAG project and close down its German operations. In 1980, OTRAG moved its production and testing facilities to a desert site in Libya
Libya
Libya is an African country in the Maghreb region of North Africa bordered by the Mediterranean Sea to the north, Egypt to the east, Sudan to the southeast, Chad and Niger to the south, and Algeria and Tunisia to the west....
. A series of successful tests were conducted at this site beginning in 1981.
Rocket design
OTRAG was a design quite different from conventional multi-stage rockets. The OTRAG design used parallel stages assembled from parallel tanktubes with flat bulkheads. The rockets were designed to carry loads up to two tons, the then usual weight of a communications satelliteCommunications satellite
A communications satellite is an artificial satellite stationed in space for the purpose of telecommunications...
, into a geostationary orbit
Geostationary orbit
A geostationary orbit is a geosynchronous orbit directly above the Earth's equator , with a period equal to the Earth's rotational period and an orbital eccentricity of approximately zero. An object in a geostationary orbit appears motionless, at a fixed position in the sky, to ground observers...
. It was planned to later increase the capacity to ten tons or more using multiple identical modules.
The rocket was to consist of individual pipes, each 27 cm in diameter and six meters long. Four of these pipes would be installed one above the other resulting in a 24 meter long fuel and oxidizer tank with a rocket engine at the lower end. The fuel was intended to be kerosene
Kerosene
Kerosene, sometimes spelled kerosine in scientific and industrial usage, also known as paraffin or paraffin oil in the United Kingdom, Hong Kong, Ireland and South Africa, is a combustible hydrocarbon liquid. The name is derived from Greek keros...
with a 50/50 mixture of nitric acid
Nitric acid
Nitric acid , also known as aqua fortis and spirit of nitre, is a highly corrosive and toxic strong acid.Colorless when pure, older samples tend to acquire a yellow cast due to the accumulation of oxides of nitrogen. If the solution contains more than 86% nitric acid, it is referred to as fuming...
and dinitrogen tetroxide
Dinitrogen tetroxide
Dinitrogen tetroxide is the chemical compound N2O4. It is a useful reagent in chemical synthesis. It forms an equilibrium mixture with nitrogen dioxide; some call this mixture dinitrogen tetroxide, while some call it nitrogen dioxide.Dinitrogen tetroxide is a powerful oxidizer, making it highly...
as an oxidiser. Ignition was provided by a small quantity of furfuryl alcohol
Furfuryl alcohol
Furfuryl alcohol, also called 2-furylmethanol or 2-furancarbinol, is an organic compound containing a furan substituted with a hydroxymethyl group. It is a clear colorless liquid when pure, but becomes amber colored upon prolonged standing. It possesses a faint burning odor and a bitter taste. ...
injected before the fuel, which ignites hypergolically (immediately and energetically) upon contact with the nitric acid. To simplify the design, pumps were not used to move the fuel to the engines, instead the fuel tanks were only 66% filled, with compressed air in the remaining space to press propellants into the ablatively
Ablation
Ablation is removal of material from the surface of an object by vaporization, chipping, or other erosive processes. This occurs in spaceflight during ascent and atmospheric reentry, glaciology, medicine, and passive fire protection.-Spaceflight:...
cooled combustion chamber. Thrust control is by partially closing the electromechanical propellant valves. Pitch and yaw control can thus be achieved by differential throttling. In principle this is extremely reliable and cheap in mass production.
The modular design was intended to result in a large cost reduction due to economies of scale
Economies of scale
Economies of scale, in microeconomics, refers to the cost advantages that an enterprise obtains due to expansion. There are factors that cause a producer’s average cost per unit to fall as the scale of output is increased. "Economies of scale" is a long run concept and refers to reductions in unit...
. The CRPU-based satellite launching rocket was estimated to cost approximately one tenth of conventional designs. Automated production processes for all components would reduce labor cost from 20% to 80% and remove the justification for reusability of spent stages.
Controversies and future outlook
Only a few political controversies are known concerning OTRAG because of concerns of neighbors of Zaire and Libya about the dual use potential of rockets. A full orbital launch vehicle was never assembled. Modules were flight tested in ZaireZaire
The Republic of Zaire was the name of the present Democratic Republic of the Congo between 27 October 1971 and 17 May 1997. The name of Zaire derives from the , itself an adaptation of the Kongo word nzere or nzadi, or "the river that swallows all rivers".-Self-proclaimed Father of the Nation:In...
and Libya
Libya
Libya is an African country in the Maghreb region of North Africa bordered by the Mediterranean Sea to the north, Egypt to the east, Sudan to the southeast, Chad and Niger to the south, and Algeria and Tunisia to the west....
. 6,000 static rocket engine tests and 16 single stage qualification tests were made to prove the concept as feasible.
The German minister of foreign affairs at that time, Hans Dietrich Genscher, is said to have finally stopped the project under pressure from France and the Soviet Union, and West Germany joined the co-financed "European rocket" Ariane project, which made the OTRAG project unnecessary and eliminated political entanglements of a still divided Germany in the early 1980s.
NASA Commercial Orbital Transportation Services
Commercial Orbital Transportation Services
Commercial Orbital Transportation Services is a NASA program to coordinate the delivery of crew and cargo to the International Space Station by private companies. The program was announced on January 18, 2006...
announcement stipulates a 50% US National ownership in vendor companies like von Braun Debus Kayser Rocket Science LLC, DE (BDKRS). This would force Kayser, a German citizen, to sell at least 50% of his shares to Americans.
More recently, the company has been advising Interorbital Systems
Interorbital Systems
Interorbital Systems Corporation is an American aerospace company based in Mojave, California. It was founded in 1996 by Roderick and Randa Milliron, who also co-founded Trans Lunar Research....
, resulting in a similar modular rocket design for their Neptune series.
John Carmack, founder and lead engineer of Armadillo Aerospace
Armadillo Aerospace
Armadillo Aerospace is an aerospace startup company based in Mesquite, Texas. Its initial goal is to build a manned suborbital spacecraft capable of space tourism, but it has stated long-term ambitions of orbital spaceflight. The company was founded by John Carmack.On October 24, 2008, Armadillo...
has stated in his monthly reports and in forum posts that he expects his path to an orbital vehicle to include modular rockets similar to OTRAG technology. Kayser, being the founding engineer of OTRAG, visited Armadillo in May, 2006 and loaned Carmack some of their original research hardware.
"I have been corresponding with Lutz [Kayser] for a few months now, and I have learned quite a few things. I seriously considered an OTRAG style massive-cluster-of-cheap-modules orbital design back when we had 98% peroxide (assumed to be a biprop with kerosene), and I have always considered it one of the viable routes to significant reduction in orbital launch costs. After really going over the trades and details with Lutz, I am quite convinced that this is the lowest development cost route to significant orbital capability. Eventually, reusable stages will take over, but I actually think that we can make it all the way to orbit on our current budget by following this path. The individual modules are less complicated than our current vehicles, and I am becoming more and more fond of high production methods over hand crafter prototypes." -- June 2006 Armadillo Aerospace Update
External links
- http://www.b14643.de/Spacerockets_1/West_Europe/OTRAG/Description/Frame.htm
- http://www.bernd-leitenberger.de/otrag.shtml very explantive article about the OTRAG history (de)
- http://www.astronautix.com/lvs/otrag.htm (en)