While Cernan and Armstrong both said they supported development of commercial space operations, "there are a myriad of technical challenges in their future yet to be overcome," Cernan said, "safety considerations which cannot be overlooked or compromised as well as a business plan and investors that they will have to satisfy."
"All this will lead to unplanned delays which will cost the American taxpayer billions of unallocated dollars and lengthen the gap from shuttle retirement to the day we can once again access LEO (low-Earth orbit) leaving us hostage as a nation to foreign powers for some indeterminate time in the future."
Armstrong agreed, saying "I am very concerned that the new plan, as I understand it, will prohibit us from having human access to low-Earth orbit on our own rockets and spacecraft until the private aerospace industry is able to qualify their hardware under development as rated for human occupancy."
"I support the encouragement of the newcomers toward their goal of lower-cost access to space," he said. "But having cut my teeth in rockets more than 50 years ago, I am not confident. The most experienced rocket engineers with whom I have spoken believe that will require many years and substantial investment to reach the necessary level of safety and reliability."
It seems to me that the retirement of the shuttle unfortunately is a given. Also, it is clear that Costellation is in the death spiral given the combination of high cost and politcal conflict. (At the point the contractors are fighting to mitigate their contract termination losses rather than save the POR.)
The only opening that is left given limited budgets has been presented by the president in his April 15 speech and this is the Orion lifeboat vehicle. We are already testing the escaple system for it. So the only real difference between an crewed vehicle and an lifeboat for the ISS is the escape system which will be need for commercial crew as well. So with in the budget the one thing we can do to close the gap is to combine the Orion-lite with an EELV to be NASA spacecraft to assure crewed access to LEO. This could be flying, I would think, by 2014 or so.
The commercial can proceed as they will to compete when they are ready. This might be a way to save a basic space program through the economic trials that are ahead.
So with in the budget the one thing we can do to close the gap is to combine the Orion-lite with an EELV to be NASA spacecraft to assure crewed access to LEO.
"The Gap" length & impacts on: personnel, material, engineering and public acceptance on programs is the issue that makes people nervous about U.S. space program. The Russian space structure for example changed following a similar vexation. But the RSA has also not really demonstrated appreciable space advancement.