NASA's Space Taxis

NASA aims to ease doubts over private space taxis.

NASA is reassuring commercial space firms that it will be a supportive customer for privately built space taxis even as it cautions that Congress could stymie efforts to foster development of such vehicles.

During an Aug. 19 industry event at NASA headquarters here, agency officials said 35 companies had responded to a May 21 NASA solicitation seeking input on the fledgling commercial crew initiative that U.S. President Barack Obama has proposed for a $5.8 billion investment over the next five years.

"We believe that we can fund up to four providers with that $5.8 billion," Phil McAlister, NASA's commercial crew planning lead, told an audience of mostly space industry executives and advocates attending the forum. "This is going to be a challenging program for both NASA and the private sector, and if somebody stumbles along the way we would like to have other providers that hopefully we can rely on." [ 6 Companies That Could Launch Humans Into Space]

Commercial space advocates — including the companies aiming to build the private space taxis and launchers NASA says it needs — remain upbeat despite a series of legislative setbacks in the U.S. House and Senate, which pared back Obama's commercial crew request in draft legislation moving through Congress and revived elements of the Moon-bound Constellation program Obama seeks to abandon.

"Of course, there is a lot of discussion here in D.C. and throughout the nation on what this program is going to be going forward," McAlister said. "We are going to adjust if necessary, but this is sort of the baseline program that we are putting together today."

McAlister said if NASA is directed to invest less money in commercial crew than the nearly $6 billion it has requested, it will have to re-evaluate its plans.

"However, competition is a fundamental aspect of the strategy," he said. "I don't want to say exactly what we would do, but we would have to trade schedule for the potential for competition, and I would say competition is a very strong driver."