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Home | Update | Latest Issue | Gallery | FR Profile | Datafiles | FR 12/96 LOCKHEED MARTIN X-33 IS A HIGH-RISK VENTURE by Wolfgang Engelhardt A new manned space transporter is to replace the American Space Shuttle in approximately 15 years. NASA's decision in favor of the futuristic VentureStar from Lockheed Martin is not undisputed among experts. The new design might run into similar problems as the Space Shuttle did. 20 years ago, NASA had announced it was able to reduce the space transport cost significantly with the new Space Shuttle. However, the opposite happened and unexpected technical problems catapulted the costs for one single flight of the Shuttle to $ 500 million. After the Challenger catastrophy ten years ago, NASA managed to stabilize the Shuttle operation in spite of some delays. Due to cost reasons, the Shuttle operation was just recently handed into the responsibility of an industry consortium founded by Lockheed Martin and Rockwell International. By choosing the X-33 project of Lockheed Martin for a Shuttle successor this summer, NASA once again stepped into technologically new territory. The development risk is not lessened by NASA's intention of delegating the responsibility to build the next Shuttle generation to the industry. The technical concept of VentureStar is much disputed among experts, even when considering the material and fuel technological progress that has been made in the past two decades. Even Lockheed Martin's new secret Aerospike propulsion system will not be able to neutralize the laws of physics. At the latest when the X-33 demonstrator is built, will it be known if the concept of a "reusable launch vehicle" works the way it was designed to. The small demonstrator will be approximately half the size of the later new large space transporter. The configuration of the demonstrator and the later VentureStar is similar to a so called lifting body which has a very little wing area, such saving weight. The X-33 is supposed to be completed by the end of 1999 and by then also having accomplished 15 flights, reaching up to 80 km altitude and a speed of Mach 15. The X-33 test model will do a vertical take-off like the Shuttle and land horizontally, being ready for another launch after only two to three days turn-around. A linear Aerospike engine is the designated propulsion system. It will be tested on a Lockheed SR-71A this year. NASA is funding the development of the demonstrator with $ 941 million, Lockheed Martin puts up 220 million dollars of its own funds for the project. VentureStar itself is supposed to be finished and operational by 2007. With a length and width of 40 m, the new space transporter will have approximately double the size of the X-33 demonstrator. VentureStar's take-off mass of approximately 1000 tons is half of what today's Shuttle weighs at lift-off: 900 tons of the hydrogen/oxygen fuel combination will supply the fuel for the seven Aerospike engines that will accelerate the 100 tons shuttle to 8 km/sec. VentureStar, like today's Shuttle, is designed to fly at an 180 km orbit with a 28,5 degree inclination, carrying up to 25 tons of payload. The payload bay will also have dimensions similar to those of the Space Shuttle. Not many details are yet known about the cockpit. Still, the astronauts will insist on the integration of some windows for an outside view, something that's not a part of today's concept. Only after testing the X-33 at the beginning of the next century will Lockheed Martin decide about a further course. According to the contract with NASA, the company must raise the necessary $ 4 to 6 billion, to build two VentureStars, itself. Lockheed Martin will only take this financial risk when the technical feasibility is discernible and the prospected lower operating costs and high flight frequency looks realistic. Also, there must be enough customer demand for 40 to 50 missions per year. Here, NASA is required to make the according affirmations. The US military and the industry are possible users also. However, it is still in the open if VentureStar will be able to reduce today's orbit transport costs of 20000 dollars per kilogram down to 2000 dollar per kilogram of payload. From page 46 of FLUG REVUE 12/96 Home | Update | Latest Issue | Gallery | FR Profile | Datafiles | FR 12/96 Copyright 1996 by Motor-Presse Stuttgart. All rights reserved. Last updated November 19, 1996