Subscribe to TimeLeftMind Set
You, of course, raise the right issues.
My first response is, yes, the bigger the rocket, the easier it will be to achieve SSTO.
You know the argument:
Many things do not get proportionately bigger when the rocket does … crew size and accommodations .. many electronics … cargo handling gear, etc.
And, of course, payload gets bigger even as a fixed fraction of GTOW.
I recall (with nostalgia) Max Hunter’s decrying of the “standing army” servicing philosophy of NASA … except for the lunar return mission that demonstrated repeated operations with a zero on-site support crew!
Your concern for funding is, I think a product of all your experience with government funded programs.
Just as in our current discussions with Buzz and others, it is not the lifetime efficiency/cost effectiveness that is your first consideration. It is the up front costs.
That’s because you are thinking of Congressional appropriations, and the cost of getting the thing built.
We should get out of that mind set and think in terms of return on investment.
If we do that, it is the recurring costs that will determine profits.
If those figures are promising, non-recurring costs become just a question of how long it will require to amortize them.
Think in terms of, e.g. petroleum pipe lines.
They dwarf the cost of the largest rocket we can imagine, but the ROI is such that they play no part in the decision to build them.
So what stands in the way of the necessarily very large SSTO/VTOL cargo rocket is a credible business plan for sustained operations to Luna that will return a profit to the builders and operators.
Now that’s where NASA and the “gov’mint” can play a really constructive part.
If they will just guarantee an annual ROI of say, 10% on government cargoes alone for at least a decade, the system is, ipso facto, a commercial success, guaranteed to at least break even.
The return on any other service provided to, for example, other than US Gov. customers will be gravy.
I know, there’s more to it than that, but my argument illustrates the change in thinking I’m attempting to inject into the discussion.
What do you say?
Bill
PS: I’ve Googled “Saturn V” some time back and just basked in the glory of the truly gargantuan hardware we built way back in the early ’60s. It really is unbelievable!
But think what we can do with the materials and methods we now have available!
Graphite epoxy, and “buckeyball” composites; much much lighter and lower power requiring more reliable electronics, sintered tungsten (just know it exists … can’t quote specs) and on and on.
I’ll bet we could build a Saturn V scale launcher that would lift twice the payload SV did.
What we lack these days is a gutsy leader like Kennedy! BH
=============
Hubert Davis hudavis@gvtc.com wrote:
Yes indeed, our first priority should be the “horse”. BTOVL SSTO is probably the simplest approach to space launch, if only we could do it reliably!
However, it must avoid the mistakes made on the Shuttle, such as labeling major elements “re-usable” when they are not and permitting huge work forces, much of them ill-used.
Possibly correct re wings. But you are right; it is very hard to give up on the grace and gentleness of winged landings. Lunar Modules did not have to contend with winds.
I like mountain launch, maybe even with a modest ground-based accelerator. Every little bit helps as we are not going to soon alter the rocket equation!
To add another small but perhaps vital aid to your concept; let’s use orbital propellant depots to refuel before entry and landing.
Now, how do we overcome the costs and risks of building a VTOVL SSTO vehicle large enough to really have both adequate payload and adequate margin?
What, btw, is your present estimate of its size, cost and schedule?
In order to work, it might have to be well beyond Saturn V size and we no longer have either Von Braun or a bottomless purse.