On Nov 19, 2009, at 6:44 AM, Andrew Crystall wrote:
On 18 Nov 2009 at 20:40, Bruce Bostwick wrote:
Considering the fact that the only two "loss of vehicle and crew"
events NASA has ever had to deal with that actually involved going
into or coming back from space (not counting Apollo 1 in that, as it
Both were directly caused by problems on-launch...
.. and would not have caused an LOV/C in either event if the geometry
of the stack didn't put components like the SRB *next to*, and not *in
tandem with*, other components like the ET, likewise with the ET and
the wing leading edges. If an SRB burn-through happened in a tandem
stack, the most that would happen would be a noticeable reduction in
SRB thrust and possibly a skewed thrust vector, which would be easily
escapable with an LES activation. And ice-saturated foam chunks
popping off the ET can only fall downstream .. in a tandem stack,
there aren't any fragile wing leading edges or TPS tiles in the way
for them to hit.
the RCC leading edge of the wing -- and since the spaceplane design
in
question does *not* include any abort options from liftoff to the
!??? What spaceplane design do you think I'm talking about? I am not
refering to any single design, and never have been.
See below.
I'd have to question why putting crew on top of a rocket is
"insane".
Because both failures on launch are related to strapping huge rockets
to the crew section, and then taking off vertically, maybe?
See above. The stack geometry of the STS is one of the most insane
things I've ever seen, and I'm quite frankly impressed that they've
only had two LOV/C's and not many more, especially in the pre-51L
days. (It says something that the current mission plans usually
include a contingency STS-3xx rescue mission, which, before 39B was
converted to Ares I support, was stacked at 39B ready to fuel up and
launch whenever an STS-1xx was flying. Word is that if NASA has to
fly an STS-3xx, the STS program will be terminated after that flight.)
a lot of ways. About the only thing Ares I/Ares V can't do is...
...Is retrieve the decades lost while NASA messed arround with the
shuttle and ISS? Oh, and let's not forget "launch affordably", "be
reuseable", "have a sensible turnarround time", "use safer hybrid
fuel systems"...
AndrewC
And there, I'll partially agree with you. I'll concede that a
spaceplane design that is better than the Orion/Ares I may exist. STS
just isn't it.
And you know what? If you come up with a propulsion system that's
more efficient than binary-fuel combustion from onboard fuel and
oxidizer, that will get a spaceplane from earth surface to LEO with
only the consumables it carries onboard, and allows carrying a payload
that doesn't run head on into diminishing returns the way the current
systems do, I'd be at the head of the line cheering for it. And if
you come up with such a thing, and can make it work, you can pretty
much write your own paycheck, either contracting to NASA or running
your own launch business. ;)
(I've considered MIPCC-type turbojet propulsion and a flying-wing
robot lifting stage for that first part of the trip out of the
troposphere, and there's some real promise there in terms of the
significantly greater Isp of air-breathing (or LOx-supplemented)
turbojet thrust vs. rocket thrust, and possibly an aerospike engine in
the orbiter to get from that jet-lift altitude to LEO. Once you're
out of the atmosphere and not dealing with significant degrees of
drag, really efficient technologies like VASIMR become an option, but
that first 50,000 feet or so is a real hurdle.)
"A human being should be able to change a diaper, plan an invasion,
butcher a hog, conn a ship, design a building, write a sonnet, balance
accounts, build a wall, set a bone, comfort the dying, take orders,
give orders, cooperate, act alone, solve equations, analyze a new
problem, pitch manure, program a computer, cook a tasty meal, fight
efficiently, die gallantly. Specialization is for insects." --
attributed to Lazarus Long by Robert A. Heinlein
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