[AR] Re: Re spacex falcon 9 landing
- From: David McMIllan <skyefire@xxxxxxxxxxxx>
- To: arocket@xxxxxxxxxxxxx
- Date: Mon, 28 Dec 2015 00:02:46 -0500
On 12/26/2015 12:30 AM, Henry Spencer wrote:
He's alive! HE'S ALIVE!!!!!!! :)
Remember that SpaceX doesn't *have* an operational reusable rocket yet
-- just an initial proof of principle, achieved with some difficulty.
Many would say that Elon is doing things the hard way, losing much of
the benefit of reusability by treating it as a later add-on.
Mmmm... well, just going by my spectator memory of how things went,
SpaceX pretty much *had* to do it that way. IIRC, they wanted to do
reusability from the beginning, found that a bridge too far, and had to
keep paring down their expectations in order to achieve a rocket that
could turn a profit before the company went bankrupt. Commercial Cargo
came along at a *very* propitious time for SpaceX -- if it hadn't,
SpaceX might still be crawling along with the Falcon 5 and trying to
stay afloat chasing the low-mass end of the launch market
... Its amusing to see the doubters continue to
doubt that they will acomplish the "next" step as each is accomplished.
Do consider that SpaceX is on its second rocket (Falcon 1 having been
a technical struggle and a complete financial flop, although a useful
pathfinder for Falcon 9) and its second attempt at first-stage
reusability (the original splash-down-and-salvage-parts concept having
been a complete failure, as some of the "doubters" correctly
predicted). The most notable thing about SpaceX is not that it always
succeeds, because sometimes it doesn't, but that it's been persistent
enough to amend its plan and press on when some part of the original
plan didn't work.
Perhaps even more notable is that they managed to create a rocket
where they *could* keep incrementally testing and adding capability,
without endangering paying cargoes *or* breaking the bank in R&D. Part
of this is probably just SpaceX's more aggressive mindset, but (from my
seat in the bleachers) a big part is also that the F9 was designed with
more emphasis on simplicity, robustness, and reliability over maximum
performance, minimum mass, and the other hallmarks of the "hydrogen
mafia." It seems to me that this created a rocket that one could tinker
with in between paying flights without having to be afraid that those
paying flights would be endangered by said tinkering. The F9 also seems
to have had a substantial degree of margin built into the design from
the beginning (and the "tinkering" keeps increasing that margin, which
promptly gets mostly used up by new tinkering and heavier/higher
payloads). This combination made it possible for SpaceX to have a
first-stage recovery flight test program that was nearly free (ignoring
the Grasshopper and 9R) -- just appending the recovery hardware and
flight ops around/after the paying work. And it allowed SpaceX to keep
adding more recovery hardware without slitting their own throats on the
payload-capacity side.
It's been interesting to watch the F9's price stay relatively
static, while the *advertised* payload capacity goes up modestly, and
the *actual* capacity goes up significantly, but mostly eaten by the
recovery hardware. If one was an accountant who never saw anything of
SpaceX aside from the price/payload in the sales brochure, one might
well think that the F9 hadn't changed much from Flight 1.
Basically, SpaceX has managed to bring a version of the Silicon
Valley " fast try/fail/fix/retry" cycle into aerospace, *without*
letting the "fail" parts of the cycle add much existential risk to
individual missions or to the company as a whole. And *that* may be the
biggest single industry-changing accomplishment that SpaceX has achieved.
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