"Consider an open ended project in which the objective is to see how far the existing data can be amalgamated and extended".
Yeah, they've done that. It's called the JSF.
If this was about risk minimisation, why not deploy them on a carrier or LHA, as they were intended to be. Would have been far easier and of more use, as the exercise would enable better training...
A lot of "noise" about nothing really. At its cruising altitude, an SST would have little effect at ground level.
The answer is simple: stick to what's in the initial contract, and ALL overruns are paid by the manufacturer. No escalation of costs to make up for it down the track if additional aircraft are...
We're talking about strike aircraft, not just fleet defence fighters.