Jerry Grey Quotations

The only valid corollary to this doctrine is not to fix the total budget, or even the budget for each element of the program, ... but to fix the annual budget cap for the program as a whole. That allows each mission date to move to the right as much as needed to stay within that annual cap.

I think Griffins team has come up with a truly workable solution that really does make sense.

The payload characteristics are certain to be much different than those of the CEV. Keeping budget control on the expenditure of six units on each flight might turn out to be an issue.

This will involve a new propellant feed system to the engine, validation of a totally different set of environmental conditions than the engine has experienced in the past, and almost certainly a re-start capability -- in vacuum -- which involves a whole new set of technical requirements.

The new five-engine SSME cluster, mounted on a stage that will certainly be very different from the orbiter in its propellant feed and thrust-vector control characteristics and its structural, aerodynamic, and environmental behavior, will require considerable engineering attention.

So although by itself the SRB is a well-proven piece of hardware, the new flight article will have many new and as yet unproven features that have yet to be human-rated.

I believe that all these technical issues, although perhaps more extensive than NASA has as yet acknowledged, are all solvable,