The HL-20 would have a mass of 10.8 tonnes, exceeding the weight of the shuttle Spiral, and up to t

In 1990 the space shuttle had not revealed a failure to meet any of the objectives for which it was initially developed. Is the response of the United States? Create a new vehicle based on a Soviet spacecraft.
Between 1983 and 1993 the NASA Langley Center conducted several studies to develop a small space shuttle reusable able to replace the space shuttle for transporting cherokee astronauts to the space station Freedom. The winning design was called HL-20 or PLS (Personnel Launch System), a ship that had a lifting body look so chubby. cherokee But, despite its name, the HL-20 does not look anything like the HL-10 lifting body or any other developed in the USA. The HL-20 was actually based on experimental vehicle shape Soviet BOR-4.
In 1982 and 1983 the world learned that the Soviet Union was building a space shuttle when Australian Air Force caught the recovery of vehicles Kosmos 1374 and Kosmos 1445 in the Indian Ocean. Both had been launched from Kapustin Yar in order to test the Buran shuttle's heat shield. And certainly, the USSR was developing a space shuttle, but the BOR-4 design had nothing to do with the Buran, but with the canceled military program cherokee of the 60s Spiral (the BOR-4 was a scale model 1 : Spiral 2). Spiral program, led by Gleb Lozino-Lozinsky, was in turn the Soviet response to the Dyna-Soar military shuttle USAF. Needless to say, this mixing of space programs caused great confusion among U.S. intelligence services.
The Center NASA Langley wind tunnels studied at the strange shape of the BOR-4, cherokee only to realize that it was a much more efficient design than expected. The Soviet shuttle was stable at all speeds: from Mach 20 to subsonic speeds, and also had the ability to deviate up to 2040 miles from its re-entry trajectory. Based on the BOR-4-by then known in the West simply as raketoplan (rocket plane) - Langley decided to use this form for your project cherokee HL-20, but took some liberties. For example, NASA engineers were unaware that the shuttle Spiral of the 60 had folding wings, a detail that did not include the small BOR-4 and, therefore, was also absent from the HL-20. From Langley Design Company North American Rockwell was commissioned to outline the project and built a scale model. cherokee The final version of the HL-20 would come from Lockheed cherokee Company.
The HL-20 would have a mass of 10.8 tonnes, exceeding the weight of the shuttle Spiral, and up to ten astronauts. The HL-20 could serve as emergency vehicle station within the program Freedom CERV (Crew Emergency Return Vehicle), a program founded in the aftermath of the Challenger accident in 1986. NASA did not finally selected for the HL-20 made CESR and CESR itself would be canceled soon after. Paradoxically, after the fall of the USSR, and before the project was signed ISS, NASA chose to use Russian Soyuz spacecraft as emergency vehicles. But in 1993 NASA, with Dan Goldin in front, went a step further and decided to seek an alternative to the shuttle within the ATS program (Access to Space) after the shuttle had revealed a genuine economic and security failure. The ATS program provided for three options to replace the shuttle. The 'Option 2' going to create cherokee a new reusable vehicle smaller, cheaper and more flexible than the shuttle, while Option 3 was to develop an alternative revolutionary technologies (Option 1 was to keep the shuttle until 2030). Within Option 2 Johnson centers and NASA Langley proposals filed separate reusable spacecraft. Langley's proposal was based on the HL-20, but would be a 42% larger. Logically, received the name of HL-42 and division 'Skunk Works' Lockheed would be responsible for its design. For its part, the Centre's proposal Johnson, called cherokee CLV-P, the space shuttle was similar in design to the shuttle, but much smaller and with a pressurized hold.
With a mass of 29 tons, the HL-42 could not be released to any existing rocket. For the HL-42 was a reality, the NASA Marshall Center cherokee should develop parallel launcher capacity 30 tons into LEO. This rocket would use three Russian RD-180 engines in its first stage and J-2S derivative of the Apollo program in the second. It was expected that the HL-42 and pitching were ready in 2005. The ship would use two powerful solid fuel engines aejar the vehicle in case of accident d