"Greg \(Strider\) Moore" wrote on Thu,
3 Jan 2019 16:50:13 -0500:

"JF Mezei" wrote in message ...

The argumenmt I am trying to make is the business model of falcon9 is
re-usability.


I think you have the cart before the horse here.
The business model is "cheaper rockets". They're obtaining this in multiple
methods. Re-usability is only one of those methods.
Note they were already cheaper than the competition before they started to
re-use their rockets.


Mayfly doesn't seem to understand that current Falcon 9 pricing at
around $64 million per launch allows a profit without re-use. Note
that DoD pays more than that because their cargos don't fit the
standard cargo interface (there's a Lockheed interface module that has
to be used) and because they have 'special requirements', not because
a booster might be lost.

If one customer pops up and requires non-re-usable
Falcon9s and becomes a major customer, then this changes the business
model because SpaceX is now needing to produce disposable Falcon9s are a
much higher ration than the original business model had antitcipated.

Ayup. A horrible problem to have when the customer is clearly willing to pay
a premium. And again, even if DoD moved ALL their launches to SpaceX, it
wouldn't make that large of an impact. I think Jeff said they currently
have the capacity to build 12 cores a year. Last year, they launched I
think 23 cores. So, even if they magically, per JF logic only use a core 3
times, they only need to build 8 cores a year. And if the DoD is willing to
pay a premium for the other 4 build cores, that's great.


Actually that was me that gave the numbers. They can produce 12 a
year without any great stress, 26 a year if they 'flex' the factory
and push as fast as they can go, and 48 a year if they work two
shifts. In any case, the three or so DoD launches a year that require
expending a booster aren't significant insofar as 'plans' go, since
they always have to assume they will lose some percentage of boosters
they try to land.

So this also changes any plans they had to reduce production so
resources can be assigned to ramping up production of BFR/BFS.

Not really. At the current rate, they'll have more cores than they'll need
in a year or two.


They've got 10 cores in hand right now. One of them has three flights
on it, two others have two flights on them, one that has one flight
and is scheduled for its second, and the rest have no flights (3
scheduled for a Falcon Heavy launch of ArabSat-6A, one schedule for
the first Crew Dragon test, and two that currently have no assigned
flight). They've lost 2 of the 12 Block 5 cores produced since they
started using them this year; one deliberately expended for the DoD
GPS-III launch and one that went in the water due to a pump failure on
one of the grid fins. That's a lot of flights left in those boosters
before SpaceX would run short. If you assume 10 flights per booster
before first major refurb, that leaves something like seven dozen
flights. That's THREE AND A HALF YEARS of currently unmanifested
flights at the current flight rate.

Which begs the following question: If Falcon9 is underpowered, and has
no margin for a high percentage of launches, was there much of a point
is making it re-usable?

That actually doesn't beg the question. First you have to prove that there's
no margin for a high percentage of flights.
There were 19 launches last year (18 F9, 1 FH).

Of those, 9 (F9, I'm not including the FH) were successful landings, 1
additional was attempted and failed.
So, less than 1/2 were not re-usable. Oh and one more was scheduled for a
landing, but due to weather and not wanting to delay the launch, they
scrapped it. (note this was a Block 4, not Block 5, so they weren't going to
refly it anyway).
Oh and another wasn't recovered because they were test other landing
options.

Mayfly is assuming that ONE launch that requires expending the booster
means that a majority of launches do based on absolutely nothing but a
devout ignoring of the actual facts.


--
"Some people get lost in thought because it's such unfamiliar
territory."
--G. Behn