Very RASV like. Also reminds me of the Air Force Trans-Atmospheric Vehicle
Program, one of the concepts was going to use a sled take-off and would have
been based at Air Force bases located inland from the coast for survivability.
According to the "Spaceflight in the Era of Aerospaceplanes" book, DARPA took a
very serious look at putting $1B into the RASV in the 1980's. They decided
instead to use the money to make a major expansion of their investment in
Stealth technology.
Charles E. (Chuck) Rogers
-----Original Message-----
From: John Schilling <john.schilling@xxxxxxxxxxxxxx>
To: arocket@xxxxxxxxxxxxx
Sent: Wed, Jan 19, 2022 1:41 pm
Subject: [AR] Re: Radian One spaceplane
On 1/19/2022 12:04 PM, Michael Clive wrote:
https://www.radianaerospace.com/#Radian-One
What are yall thinking about this one? Would love to hear from my fellow
former Xcorians.
Is the world craving an SSTO? Could one design a reusable upper stage for a
falcon?
Will reusable heat shields ever work?
I don't think the world is craving an SSTO, but they would probably find
good ways to use one with a reasonable payload capacity, reflight rate, and
operating cost. From the limited information available, Radian One's proposal
looks sort of like the old Boeing RASV concept, which was at least plausible.
Generally, TSTO probably offers better near-term performance with SSTO maybe
coming out ahead for a mature system operating at very high flight rates; not
where I would put my money right now if I had that sort of money, but happy to
see someone else give it a try.
Reusable upper stage for a Falcon (or New Glenn, if/when that ever flies)
would be easier and lower risk to develop, and still quite useful. I looked at
the numbers for that in one of my Space Access presentations; I came up with
conceptual designs that would deliver 6.9 metric tons to a 400 km/30 deg orbit
from a Falcon 9 Block 5, 27.9 metric tons from a Falcon heavy, and 17.5 metric
tons from a New Glenn. Elon is of course betting that Super Heavy + Starship
will make all of this moot, which would be great but I'm not thrilled with the
all-eggs-in-one-shiny-new-basket nature of that approach. As for reusable heat
shields, I think those are very likely to work if you aren't pushing the limits
too much. The combination of reusable TPS and SSTO is a hard one, though,
because the razor-thin mass margins of an SSTO (at least if you want anything
left over for payload) mean pushing your TPS technology to the limit. I'm
agnostic as to which of the various proposed reusable-TPS technologies will
work best. Well, OK, I think it's fairly likely that a transpiration-cooled TPS
system will offer the best performance when someone finally debugs it, but I
don't want to be the person debugging that system. John Schilling
