Nasa calls for new ISS taxis
Cape Canaveral - Nasa is looking for at least two US firms to design and build space taxis to ferry astronauts to and from the International Space Station, programme managers said.
Nasa plans to invest $300m to $500m in each of the firms selected under new 21-month partnership agreements, Ed Mango, manager of Nasa's Commercial Crew programme, said at an industry briefing at the Kennedy Space Centre prior to the release of a solicitation.
The new programme aims to build upon previous Nasa investments in companies designing commercial passenger spaceships.
With the retirement of the US space shuttles in 2011, Russia has a monopoly on flying crews to the station, a $100bn orbiting laboratory for medical, materials science and other research.
China, the only other country that has flown people in orbit, is not a partner in the project.
Russia charges Nasa about $60m per person for rides to the station, which flies about 385km above Earth and is staffed by rotating crews of six astronauts from the US, Russia, Europe, Japan and Canada.
Winning firms would have until May 2014 to complete their integrated designs, with the intention, if funding allows, to test fly their spaceships in orbit by the middle of the decade, Mango said.
Goals of the demonstration flight include reaching an altitude of at least 370km, manoeuvring in space and staying in orbit for at least three days, Mango said.
The test ships should be capable of carrying at least four people, he added.
Since 2010, Nasa has invested a total of $365.5m in private companies, including $130.9m in Boeing, $125.6m in Sierra Nevada Corp and $75m in Space Exploration Technologies, or SpaceX.
Boeing is developing a capsule, called the CST-100, which would fly on an Atlas 5 rocket. Nasa has already selected SpaceX to fly cargo to the station. The company plans to upgrade its Dragon freighter and Falcon 9 rocket to fly crew as well.
Sierra Nevada is developing a winged vehicle called the Dream Chaser that resembles a miniature space shuttle. Like Boeing's spaceship, it too would launch aboard Atlas 5 rockets, which are manufactured and sold by United Launch Alliance, a Boeing-Lockheed Martin partnership.
Nasa has $406m to spend on commercial crew programmes for the year that began on October 1. Mango said about 75% of that money is available for the next phase of the programme, with awards expected in July or August.
Because of future funding uncertainties, Nasa is asking its potential partners to propose how they would proceed with flat funding of $400m a year after 2014, as well as how much they would need to get to a flight demonstration.
"If we have multiple partners, we think the most we might be able to give them in the long term might be something along the lines of $400m per partner," Mango said.
Nasa hopes to be able to fly its astronauts on commercial carriers by about 2017.