
Alan,

	don't forget,  a HUGE  cost for airliner developement is FAA
certification.  the joke is when the paperwork  exceeds teh weight
of the airplane,  it will fly.

The SR-71, and teh X-15  both highly ambitious  aero-space projects were done
on very narrow engineering budgets.   Partly because they didn't spend much
on paper  pushing.   There is some company in missouri  trying to
get funding to build light commercial transporters  on a low cost basis,
mostly by reducing FAA  certification costs.