Bill,
True, and often in recent years our disputations have centered on
whether/when reuse might specifically be more economic than expenditure
for SpaceX in the instance of F9. Glad we've finally agreed on that point!
One step at a time, into the future...
best
Henry
On 4/4/2020 2:07 PM, William Claybaugh wrote:
Henry:
When RLV’s will be more economic than ELV’s remains unclear to me and many others. I doubt I have ever suggested that they would never be lower cost.
Our dispute has always been about when, not if.
Bill
On Sat, Apr 4, 2020 at 3:03 PM Henry Vanderbilt <hvanderbilt@xxxxxxxxxxxxxx <mailto:hvanderbilt@xxxxxxxxxxxxxx>> wrote:
Bill,
And you've never disputed the matter with me or anyone else here
since? Okay...
best
Henry
On 4/4/2020 11:46 AM, William Claybaugh wrote:
Henry:
You really need to revisit your assumptions about me. Griffin
and I proved that in 1994.
Bill
On Sat, Apr 4, 2020 at 12:44 PM Henry Vanderbilt
<hvanderbilt@xxxxxxxxxxxxxx <mailto:hvanderbilt@xxxxxxxxxxxxxx>>
wrote:
Ah! We agree that reuse is a benefit!
This is progress...
best
Henry
On 4/4/2020 11:21 AM, William Claybaugh wrote:
Henry:
Have it your way if you wish.
I am certain that Elon will tell you that the first benefit
of reuse is in spreading depreciation; and, that spreading
amortization is a very second order effect.
Bill
On Sat, Apr 4, 2020 at 12:10 PM Henry Vanderbilt
<hvanderbilt@xxxxxxxxxxxxxx
<mailto:hvanderbilt@xxxxxxxxxxxxxx>> wrote:
Bill,
Terminological quibbling aside, what I'm talking about
is something alien to the cost-plus trad space industry:
Commercial businesses ferociously controlling their
costs, both upfront and ongoing.
Up-front costs are like poison, while ongoing operating
costs are merely like heroin. Both are worth
considerable effort and ingenuity to minimize. And
SpaceX, in successfully going for reusability, has
avoided both a big initial chunk of poison and a
fair-sized heroin habit, both implicit in the trad
cost-plus approach to eventually flying circa sixty
booster cores a year.
Given we once again seem to be talking past each other -
it's good to be back! - perhaps best we simply continue
to disagree about this being a significant part of why
SpaceX is cleaning the trad industry's clock.
cheers
Henry
On 3/24/2020 8:19 AM, William Claybaugh wrote:
Henry:
Terms matter: what you are talking about is
depreciation, not production savings.
I’m will to be educated but I would be shocked if
making 1/5 as many vehicles resulted in a production
system 1/5 the previous size: that is simply not how
production works.
There are high fixed costs in any production line as
well as minimum costs.
Bill
On Tue, Mar 24, 2020 at 8:49 AM Henry Vanderbilt
<hvanderbilt@xxxxxxxxxxxxxx
<mailto:hvanderbilt@xxxxxxxxxxxxxx>> wrote:
Bill,
The long-term production difference in question, by
definition, is a factor of five times. Not 2:1
either way around a base of 12/year.
SpaceX knew this going in. Being sensible people
/not/ locked into the established way of doing
things, they likely would have set up a production
establishment for sixty expended cores a year very
differently than they did the plant for ~12 5X
reused cores. Twelve a year, as you say, is pretty
much craft production - modest production tooling
and a lot of very skilled hand labor, low plant
investment but relatively high ongoing personnel
cost. 60X a year is still not exactly Willow Run,
but sensible people planning that would very likely
invest considerably more in plant and tooling so as
to not require5X the skilled personnel plus 2nd and
3rd shift differentials, working in
~2X the modest 12/year plant (assuming it was
originally run one-shift).
Yes, I oversimplified by saying "1/5th the size of
production establishment". Thought I'd allowed for
that sufficiently with "(to a first
approximation)", oh well. And yes, "size" was not
quite the mot juste; "cost" might have been closer
to what I was driving at.
My basic point: SpaceX gambled on 5X reusability to
greatly reduce their up-front investment in, and
ongoing cost of, F9 booster production. And they
seem to have won. By a quick count, 92 F9 booster
core flights so far, and already over half of those
(51) have been used boosters. The used proportion
will only rise from here. And they did this on the
up-front investment for a dozen a year.
In other words, one of the reasons they're so far
ahead of the game now is they gambled and won
bigtime on a major-capital saving shortcut at the
start. I hope that's clearer.
Henry
On 3/23/2020 2:00 PM, William Claybaugh wrote:
Henry:
It isn’t clear to me that there is all that much
difference between making 12 per year and making 6
or 24.
One saves the material costs and the marginal
labor cost but the infrastructure doesn’t (or at
least shouldn’t) change much over that range of
production.
That said, if you optimize your system for four
units per year you will find making 24 more costly
than a line optimized for twenty-four.
But rates of a few dozen per year—or a few
hundred—all fall into “craft production” and are
not going to show economically significant
variation on production costs. The benefit of
even a few reuses is in the depreciation of the
hardware cost over multiple launches.
Bill
On Mon, Mar 23, 2020 at 2:24 PM Henry Vanderbilt
<hvanderbilt@xxxxxxxxxxxxxx
<mailto:hvanderbilt@xxxxxxxxxxxxxx>> wrote:
Another way of looking at this that I think is
relevant: 5-reuse boosters allows SpaceX to
support a given flight rate with (to a first
approximation) 1/5th the size of production
establishment they'd need for fully expendable
operations.
Henry
On 3/23/2020 8:12 AM, William Claybaugh wrote:
Robert:
There is too little data to make any
assertion about stage longevity at this point.
However, ignoring propellant and launch
operations costs, five flights per booster
would indicate a cost per booster at 20% of
the manufactured cost, not including
refurbishment between flights. The former is
around $30-35 million, so $6-7 Million per
flight, again, not including refurbishment.
If an overhaul costs more than about $6
million, it would make more sense to simply
build a new five launch lifetime stage.
We may note that compared to a $50 million
price, these depreciated stage cost estimates
suggest either a good deal of profit or that
other costs (launch operations,
refurbishment) are high.
Bill
On Mon, Mar 23, 2020 at 8:51 AM Robert
Steinke <robert.steinke@xxxxxxxxx
<mailto:robert.steinke@xxxxxxxxx>> wrote:
From hobbyspace.com
<http://hobbyspace.com> about the latest
Falcon 9 launch:
" A first stage engine shut down
prematurely (just before staging) but had
no effect on the mission as the other 8
engines made up the difference. The
booster also failed to make a successful
landing on a sea platform. This was the
fifth flight of this booster."
That was after a previous launch attempt
aborted due to slightly high power.
Wonderful demonstration of engine-out
fault tolerance, but it does look like
the rocket is showing some wear and tear
after 5 flights. What does this do to
their economics if stages need an
overhaul/have an increased chance of loss
of vehicle after only 5 flights?
