"Pat Flannery" wrote in message
...

Jeff Findley wrote:
False, especailly for an expendable SSTO. An expendable SSTO isn't all
that hard to do, it's just that no one has tried. The "performance uber
alles" philosophy of your typical aerospace engineer makes them *really*
want to drop some of the heavy bits on the way up, even if it adds
complexity and cost to the design because they always think that the
performance gained is worth the added cost.

You can see the germ of Atlas in North Amercian Aviation's HATV design
from 1946: http://history.nasa.gov/SP-4202/p1-10.jpg
You can just see an engineer looking at that, and thinking: "Now , if we
could jettison the eight small motors once a lot of the fuel was burnt..."

Kind of, sort of, if you moved as much as possible into the part you drop.
As Henry pointed out, Atlas dropped the tank pressurization system with the
booster engines. In the HATV design, that system isn't very close to the
eight small motors.

Jeff
--
"They that can give up essential liberty to obtain a
little temporary safety deserve neither liberty nor
safety"
- B. Franklin, Bartlett's Familiar Quotations (1919)