Paul:
Look up “the time value of money”.
Because money in future is worth less than money today (naively, due to
inflation but in fact do to alternative returns on investment) it follows
that $600 million dumped into a space startup has to generate a return in
keeping w/ alternative investments. Since such returns for very safe
investments run a minimum of 7% over the long run and since the VG
investment has had no return for nearly a decade, a simple calculation will
show that there is now *no* plausible profit level that can provide an
economic return.
In short, like the other space startups, there is no chance that investors
in VG will ever make a profit; it is mathematically likely they will never
even get their investment back in real dollars.
Rand is correct.
Bill
On Fri, Apr 6, 2018 at 1:28 PM Paul Mueller <paul.mueller.iii@xxxxxxxxx>
wrote:
With space tourism still in its infancy and no way to know what the market
will be like, I don't see how Rand can definitively say SS2 will "never be
a commercial success." It doesn't seem to be an overly costly way of
operating (and true commercial launch is also still in its infancy to
really know what the costs can be driven to).
I'm also not clear on what is inherently wrong with their
concept...horizontal launch, reusable first stage (WhiteKnight), suborbital
only, hybrid propulsion, nitrous oxide oxidizer, feathering, horizontal
runway landing? Or a combination of these? Or something else entirely?
Seems premature to make such judgments without more operational (and
market) experience with their approach.
Paul M
On Fri, Apr 6, 2018 at 8:48 AM, Edward Wranosky <edwardcw@xxxxxxxxx>
wrote:
I've done hobby HPR nitrous hybrids for ~15 years. The largest I've
tested is 35 pounds N2O. I've come to the conclusion that any bigger, and
I'd switch to LOX. But probably not, because I enjoy testing and
developing different bits of injector hardware for the size I'm at now just
to see if it can be done. Plus, if I want to get much larger, APCP solids
offer more ooomph per unit effort.
Edward
On Thu, Apr 5, 2018 at 5:19 PM, Rand Simberg <simberg@xxxxxxxxxxxxxxx>
wrote:
Congrats for a successful flight of a concept they should have abandoned
over a decade ago, and will never be a commercial success. #SunkCostTrap
On 2018-04-05 19:15, Henry Vanderbilt wrote:
My recollection is that they were injecting both methane and helium at
various points in the burn - half-recalled, methane to help ignition
and helium for stability?
Don't know whether they're still doing that or not. But they were
having problems that caused the switch to nylon in the first place, so
they may well still be taking extraordinary measures to tame the beast
after switching back.
My take on the lesson to be learned is that large nitrous hybrids are
more trouble than they're worth. Three different sets of
fluid-injection plumbing (if still present, of course) negates any
simplicity advantage over a liquid biprop, I'd say.
But regardless, congrats to everyone involved in the successful
flight, and best of luck for safe ops from here on.
Henry
On 4/5/2018 4:02 PM, Paul Mueller wrote:
Congrats to Virgin Galactic for a successful powered flight of VSS
Unity today.
Interesting that they switched back to an HTPB-based fuel after
switching to a nylon-based one for their last powered flights over 3 years
ago (IIRC). As I recall, they had some issues with combustion stability
with the nylon fuel grain so they had added some other systems (methane?)
to help with that. Hopefully that complexity is gone if they've switched
back to HTPB.
My recollections may be wrong on all this--wondering if any arocket
folks can comment...
Anyway, good to see them flying again!
Paul M