Ian:
The table is labor hours vs. vehicle (not payload) dry mass.
Note that “subsonic” includes other supersonic aircraft besides Concorde
but does not include DC-X.
Bill
On Sat, Feb 17, 2018 at 8:26 AM Ian Woollard <ian.woollard@xxxxxxxxx> wrote:
Kinda weird to see Concorde at the bottom of the labour intensity ladder,
and below the 'subsonic' trend line. ;)
I don't know the context but it would probably be more useful to see a
table per unit of payload, rather than a graph against payload mass,
Concorde was particularly heavy per unit payload compared to the subsonics.
On 17 February 2018 at 14:22, William Claybaugh <wclaybaugh2@xxxxxxxxx>
wrote:
All:
My sincere apologies for this obviously incorrect post.
There is a four order of magnitude difference in *Labor Intensity*
between subsonic aircraft and space launch systems (see the attached
chart), not in cost per pound.
By way of explanation (but not excuse), let me admit too putting in some
fairly long hours lately on this SSTO study and being in the middle of
writing about labor costs when I dashed off this stupid post.
My apologies to all,
Bill
On Fri, Feb 16, 2018 at 2:49 PM, William Claybaugh <wclaybaugh2@xxxxxxxxx
wrote:
Henry:
To first order and to date, stuff that goes to orbit costs about four
orders of magnitude more than subsonic stuff, per pound.
SpaceX has pulled about half an order of magnitude out of that, leaving
the difference—in their case only—at almost exactly four orders of
magnitude.
Bill
On Fri, Feb 16, 2018 at 1:28 PM Henry Vanderbilt <
hvanderbilt@xxxxxxxxxxxxxx> wrote:
Cost-per-airframe/engine pound certainly scales up with higher vehicle
performance.
Development cost per project has a less linear relationship with raw
vehicle performance - other significant variables also apply.
See my previous remarks about the different demands of achieving a
profitable performance increment over existing mature-technology ailiner
competition, versus developing a Good Enough version of a radically new
space transport approach that inherently brings with it a significant
performance edge.
And on the gripping hand, setting up for economic serial production of
hundreds-to-thousands of copies of a big state-of-the-art airliner is a
major expense that developers of advanced rockets generally avoid.
In fact, SpaceX's investment in reusability can be viewed as primarily a
way to support their high (for the old expendable industry) flight rates
with a much smaller/cheaper booster core production establishment than
they'd otherwise need.
To a first approximation, a successful Mark 1 version fast-turnaround
SSTO space transport will not immediately require mass production. More
like single digit numbers of hand-built copies.
Later marks, as the market radically expands, will be a different story.
But the revenue from the early marks will be there to help support
establishing higher-rate production. Not an issue for funding the
initial push to market.
Henry Vanderbilt
On 2/15/2018 3:15 PM, William Claybaugh wrote:
Rick:the
Productivity gains in the aerospace sector have pretty much matched
inflation over the period since the 747 was developed; accordingly, a
large passenger aircraft should cost—in today’s dollars—pretty much
same as a 747 cost in then dollars. $1 Billion by your estimate.the
The other glaring issue here is that a subsonic aircraft is not
comparable to a Mach 25 spaceship; trying to use the one to estimate
cost of the other guarantees underestimating.roughly
Bill
On Thu, Feb 15, 2018 at 1:42 PM Rick Wills <willsrw@xxxxxxxxx
<mailto:willsrw@xxxxxxxxx>> wrote:
Henry
I'll throw my 2 cents in here.
$20B should be an upper limit for spaceplane/launch vehicle
development. My estimate is $14B to $17B. A reusable orbital
launch vehicle may or not be an SSTO but it needs to be 100%
reusable. My rational for the estimate is Boeing spent $1 Billion
to develop the 747 with first flight in 1969. Today, that's
$7B. Rough order of magnitude is double Boeing's cost; than adddevelop.
20% for cost overruns. I can see why some people might argue $20B
to $40B; Boeing Dreamliner is reported to have cost $30B to
However, SpaceX could hit 100% reusable with a reusable upperstage.
discussed
On Monday afternoon, I spoke to freshman mechanical and aerospace
engineering students at the University of Dayton on the subject of
the Engineering Profession. In my "lessons learned" section, I
discussed bias. Yep, we all got them. As an example, I
my bias about what a reusable orbital launch vehicle would like.My
long held view was a reusable launch vehicle would be "aircrafttime.
like": wings, landing gear, etc, and of course a pilot. (full
disclosure, I hold a commercial pilot rating and am engineer). In
preparing for the talk, I realize this bias when as far back as my
childhood looking at Pratt & Coggins book "By Spaceship to the
Moon". It's 1950 technology but the science is solid for the
In it, there is a nice drawing of a large winged vehicle, theystage
called it a supply ship. The vehicle was taking off horizontally
with a rocket powered sled. My five year old self looked at that
and thought, "that's neat". I now understand the technical,
developmental, political, and financial issues with these sorts of
system configurations but the bias was implanted. Now Space X
comes along and shows how recovering an intact undamaged first
can return a profit. Biases do die hard, but it's hard to argueVanderbilt
with success.
Take Care and Be Safe,
Rick Wills
Still waiting for Buck Rogers
-----Original Message-----
From: arocket-bounce@xxxxxxxxxxxxx
<mailto:arocket-bounce@xxxxxxxxxxxxx>
[mailto:arocket-bounce@xxxxxxxxxxxxx
<mailto:arocket-bounce@xxxxxxxxxxxxx>] On Behalf Of Henry
Sent: Thursday, February 15, 2018 1:54 PMless
To: arocket@xxxxxxxxxxxxx <mailto:arocket@xxxxxxxxxxxxx>
Subject: [AR] Re: SSTO fuels (was Re: SSTO)
On 2/13/2018 7:14 PM, William Claybaugh wrote:
> I have seen that paper. For something as technically (much
> economically) difficult as SSTO it seems a little light: evenmuch
> more detailed analysis doesn’t often lead to much confidencethat I
> ought to recommend dropping $20 or $40 billion on one solutionif
over another.
My two cents worth: If fielding a useful SSTO space transport is
costing you $20 to $40 billion, you're doing something very wrong.
That's the sort of price tag you get by farming it out to the
existing cost-plus government aerospace houses, supervised by an
existing high-overhead government R&D bureaucracy.
At the end of that process you may or may not get a useful space
transport, but lots of people will have had decades of low-stress
white-collar job security. Fine if that's your objective -
typically if you're a Congressman and they're your constituents -
you actually care about building useful space transportation, notso
much.Blue)
Done as previously described, build your own private team up doing
methodical risk-reduction then development (as with SpaceX and
it should be perhaps a tenth of that.
Henry V
--
-Ian Woollard
Sent from my Turing machine