OTRAG

OTRAG (German: Orbital Transport und Raketen AG, or Orbital Transport and Rockets, Inc.), was a German company which planned in the late 1970s and early 1980s to develop an alternative propulsion system for rockets. OTRAG was the first commercial developer and producer of space launch vehicles.

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 satellite launch vehicle.

As developed, the OTRAG rocket represents 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 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 at Shaba, Zaire (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.

Technique

OTRAG was a design quite different from the conventional multi-stage rockets. The OTRAG design consisted of parallel stages assembled from parallel tanktubes with flat bulkheads. The rockets were designed to carry loads up to two tons, the weight of a then usual communications satellite, 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 and nitric acid. 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. This principle is extremely reliable and cheap in mass production.

The modular design results obviously in a huge cost reduction because of the law of mass production. The CRPU-based satellite launching rocket costs approximately one tenth the cost of conventional designs.

Automated production processes for all components reduce labor cost from 80% to 20% and remove the justification for reusability of spent stages. The reuse of a beer can after being opened, drunk empty, kicked around in seawater or sand is doable but not commercially viable except for pure material recycling. Analogically the developers of this very low cost launcher project Wernher von Braun, Kurt Debus, and Lutz Kayser preferred mass production and use in flight of new rockets and thus earning a rapidly increasing confidence level over time of 6 sigma. This means a goal of not more than 3-4 malfunctions per million operations per CRPU could human-rate a family of medium, high, and very high payload launchers from 1 to 128 tons in 4 to 8 years to serve NASA's and commercial satellite operators needs.

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 Zaire and Libya. 6000 static rocket engine tests and 16 single stage qualification tests have proven 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 W-Germany joined the co-financed "European rocket" Ariane project, which made the OTRAG project unnecessary and eliminated political entanglements in the early eighties of last century of a still divided Germany.

No government was interested at that time to reduce cost and commercial satellite operators had no choice than to accept the high launch cost.

Today as commercial access to space is promoted by the US Government this fully developed technology can be used to achieve transport cost into Low Earth Orbit of approx. 1000$/lb payload in contrast to present cost greater than 10000$/lb. Thus the innovative Common Rocket Propulsion Units CRPU can assist NASA in the recently announced Commercial Orbit Transportation Service (COTS) program to transport payload and crew to the International Space Station ISS and later to transport material and rocket fuel into LEO to fill up NASA Crew Exploration Vehicles CEV.

It is estimated that the total cost for transport of lunar and martian exploration and station construction material can be reduced by approx. US$ 30 Billion assuming a mass requirement in LEO of 3,000 tons until 2030.

It remains to be seen if Lutz Kayser can convince private investors that now the time is ripe to complete this venture. The necessary US$ 100 Million for the inventions and technological breakthroughs in rocket technology have been payed for in the last 30 years and are a solid foundation to proceed to CRPU mass production and clustered flights to qualify stage separation and orbital insertion for a 3-stage launcher

It is presently not known if and with whom Lutz Layser negotiates joint ventures; however the recent NASA COTS announcement stipulates a 50% US National ownership in vendor companies like von Braun Debus Kayser Rocket Science LLC, DE (BDKRS). This will force Lutz Kayser to sell at least 50% of his shares to Americans, since he is a German citizen.