Monday, May 18, 2009

Fly-Back Boosters, Reprised

Last week, the USAF released study information concerning
lower cost, shorter lead time, access to space. I think
it's funny that the USAF was studying similar proposals
back in 1988. Amongst more familiar designs were the first
drawings I'd seen of fly-back booster systems. They add
a lot to the liftoff weight, but reusability is greatly
enhanced by not dipping the booster in salt water, like the
shuttle strap-ons. Other typical features include motor
commonality, where possible, and limited reusability.
An example would be; useing the motor[s] X number of
times in the fly-back booster, then transferring them to
the disposable core stage[s] for one last trip.

I am by no means bitching. I like these systems. However
it is somewhat amusing how history repeats itself, only at
twice the price now. There are no technical hurdles to
overcome now, and there really weren't any then either.
The Air Force isn't asking for peak performance. Larger
base capacity makes up for moderate performance coupled
with higher reliability. The difference between pro-stock
class and top-fuel dragsters or funny cars at the drag strip.

The big difference between the old fly-back system and the
new, is that with the old, it was primarily a very heavy lift
system [105,000-160,000 LB/LEO], while the new approach
is part of a fully rounded low to heavy capacity [peak 64.000
Lb/LEO] program. I like modular systems, especially when
there are enough modules to fully utilize the concept.

Stay tuned for some modular space system gripes, coming soon.

1 comment:

  1. When I wrote this, I deliberately left out the question; "What does the Air Force want to lift that weighs as much as 160,000 Lbs???"
    I need to dig into my archives and see how heavy some of those really neat payloads weighed. KH's? Skylab? MOL? FOBS?
    Of course secret Star Wars operational systems might be quite big, and with stealthing and armor... Heavy indeed.