On 2021-05-10 7:11 AM, Jeff Findley wrote:
I have no doubt that SpaceX will iterate Raptor into a reliable engine.
Starship and Super Heavy are still under development, but they too are
using iterative development. If all goes well, we'll see Starship prove
out in orbit cryogenic refueling and reuse of an upper stage. These are
both things that other companies could have been working on decades ago,
but chose not to.

Jeff


There are essentially two issues here you raise with Old Space and a
third meta-issue that I think deserve a bit more reflection upon as to
why we ended up where we did relative to SpaceX.

I'll start with the second issue last. And that is the idea that 'other
companies' could have been working on reusable rockets decades ago. From
a technical perspective, prior to the 1980s I don't think so. Stuffing
the automation required into a rocket that didn't make it the size of a
Saturn just wasn't feasible. I use the automation in the Space Shuttle
as case one as to why. Somewhere in the mid to late 80's, from an
electronics perspective anyway (my area of knowledge) I think avionics
for controlled rocket reentry became feasible. And with designs like
DC-X we saw it was not only possible but realizable. And that was
McDonnell Douglas in the early 1990s. 3 decades back good enough? But
why did it end? That gets to my meta reason at the end.

The first issue has been discussed here before and that is the iterative
development model. SpaceX worked on a plan for itself based on prior
achievements but it didn't do this in a vacuum. Without COTS / CCDEV and
NASA funding it's not clear they could have bridged the gap between
Falcon 1 and Falcon 9. That was a big leap. That Falcon 1 achieved orbit
earned them cred with NASA that gained them the funding they needed to
continue. The commercial satellite contracts followed, but if memory
serves the com-sat folks were not ahead of NASA in line and none before
Falcon 9. NASA took care of the funding, but the iterative design work
and the dedication to reuse was a goal derived from a unique goal of
affordability that Elon baked into the company from the beginning. And
why is that important? Here is where we get to the meta-issue.

Until SpaceX came along, Old Space companies were more than happy to let
NASA and the USAF and to a lesser extent, DARPA determine what the goals
and objectives of their rocket programs should be. There was NO, ZERO,
ZILCH self-motivation. None of the Old Space companies had plans or
goals of their own for space exploration. Unlike their aircraft
divisions which were driven by commercial airlines, only the government
was in the drivers seat for rocketry. And because of that, it stagnated.
Well stagnated is not perhaps the right word. Because rocketry in the US
was not a private enterprise after WWII. After Goddard's experiments
there was no follow on. Perhaps in terms of weather observation there
might have been a glimmer of a commercial enterprise, but doubtful since
even before WWII weather observation and forecasting was considered a
domain of the government. The nearest idea I can come up with for
commercialization of rocketry was orbiting satellites as more reliable
communication relays than shortwave. But to fully leverage that
reliability would have required many, many LEO satellites and technology
that was unavailable to Goddard in his time. GEO would have been out of
the question until the science and engineering had advanced to a higher
state of the art. It's hard to image any one US company with pockets
deep enough to fund that effort.

The truly novel thing about SpaceX, is not that it built affordable
rockets. Not that it built re-usable rockets. Not that is uses
incremental designs. Nope the truly unique thing about SpaceX is that it
was the first rocket company to be -self-motivated-. The ideas and the
reasons for its designs came from Elon Musk's desire to get to Mars and
to figure out ways to enable that. Without the motivation of 'doing
space' in their own way, I don't think any of those breakthroughs that
followed would have taken place. NASA kept them alive at a key juncture
in their evolution, but now it's beginning to take shape, with
commercial contracts to keep it alive, and everyone else can come along
for the ride.

Dave