Author Topic: Sun Synchronous Medium Launcher  (Read 17540 times)

Offline guckyfan

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Re: Sun Synchronous Medium Launcher
« Reply #20 on: 03/31/2015 12:31 pm »


I don't think you understand..

Well, one of us does not understand, it seems. It is what Matsumori stated.

Offline QuantumG

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Re: Sun Synchronous Medium Launcher
« Reply #21 on: 03/31/2015 12:35 pm »
Well, one of us does not understand, it seems. It is what Matsumori stated.

Huh? You think that just because SpaceX aims to ramp up production that they're going to be able to meet all forseeable demand instantly? Suddenly SpaceX is beyond basic economics?
Human spaceflight is basically just LARPing now.

Offline guckyfan

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Re: Sun Synchronous Medium Launcher
« Reply #22 on: 03/31/2015 02:34 pm »
Well, one of us does not understand, it seems. It is what Matsumori stated.

Huh? You think that just because SpaceX aims to ramp up production that they're going to be able to meet all forseeable demand instantly? Suddenly SpaceX is beyond basic economics?

Who talked about all foreseeable demand? I certainly did not. They will file significant capacity though. Capacity will ramp up from there as will demand.

The 4000 satellites with 5 year turnover will require 800 satellites every year. So if in 5 as indicated by Elon Musk or maybe 7 years they can fly the first 800 they will have very significant capacity in orbit. Ramping that up by another 800 every year should keep up with rising demand.

Offline su27k

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Re: Sun Synchronous Medium Launcher
« Reply #23 on: 03/31/2015 04:24 pm »
There will always be people willing to pay more to fly sooner.

Not a lot of people I would presume... To fly sooner you have to have a payload, and I suspect it takes a lot longer to build the payload than readying a reusable Falcon 9.

Offline simonbp

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Re: Sun Synchronous Medium Launcher
« Reply #24 on: 03/31/2015 11:32 pm »
The "pay more to fly sooner" market may mainly be USAF wanting on-demand launches to a particular inclination and phasing (in response to a military situation). IMHO that's the market Stratolaunch is going after.

But Stratolaunch could also fill the SSO role that Ed was asking about, and from CCAFS to get cheaper payload processing.

Offline edkyle99

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Re: Sun Synchronous Medium Launcher
« Reply #25 on: 04/01/2015 02:27 pm »
This is irrelevant when a new launch vehicle development will cost in the neighborhood of $1 billion (or more) - You then have to judge that cost against A) just producing more of the slightly more powerful LV (reducing its marginal cost) and B) the possibility of dual manifesting. Or doing both.

Then the decision to build a brand new less capable LV starts to look questionable. The tool that you have may be overbuilt, but it is one that you have, and using it makes sense.
If it really does cost $1 billion to develop, but the smaller launch vehicle costs half as much to fly as the oversized vehicle (let's say it costs $40 million less per flight) the payback occurs after 25 flights, or 33 for $30 million, or 20 for $50 million, and so on.

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Offline guckyfan

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Re: Sun Synchronous Medium Launcher
« Reply #26 on: 04/01/2015 02:45 pm »
(let's say it costs $40 million less per flight)

Hard to do when the bigger vehicle costs 40 million $ per flight. Or even when it costs 60 million $ per flight.

Offline edkyle99

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Re: Sun Synchronous Medium Launcher
« Reply #27 on: 04/02/2015 01:04 pm »
(let's say it costs $40 million less per flight)

Hard to do when the bigger vehicle costs 40 million $ per flight. Or even when it costs 60 million $ per flight.
Whatever Falcon 9 really costs, a rocket that uses 1/3rd as many engines should cost perhaps 1/2 as much, or less.

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Offline notsorandom

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Re: Sun Synchronous Medium Launcher
« Reply #28 on: 04/02/2015 01:56 pm »
This thread was started more as a thought experiment than a business proposal. If SpaceX can get your payload to orbit reliably for the best price then of course you go with them and don't care how over capacity the rocket is. However its no fun to speculate about that.

Offline edkyle99

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Re: Sun Synchronous Medium Launcher
« Reply #29 on: 04/02/2015 05:54 pm »
This thread was started more as a thought experiment than a business proposal. If SpaceX can get your payload to orbit reliably for the best price then of course you go with them and don't care how over capacity the rocket is. However its no fun to speculate about that.
What I wonder is, since SpaceX, ULA, and Orbital all seem focused on those heavier payloads, whether there is market opportunity for someone else.  In my view it should be possible to undercut the costs of their larger rockets and the infrastructure that goes with them if a system is designed specifically to handle these smaller payloads.

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Offline Space Ghost 1962

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Re: Sun Synchronous Medium Launcher
« Reply #30 on: 04/02/2015 06:41 pm »
This thread was started more as a thought experiment than a business proposal. If SpaceX can get your payload to orbit reliably for the best price then of course you go with them and don't care how over capacity the rocket is. However its no fun to speculate about that.
... whether there is market opportunity for someone else.

Antares addresses a smaller market than either SX or ULA (many others too). How has that made them more successful? Answer - not really.

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...  In my view it should be possible to undercut the costs of their larger rockets and the infrastructure that goes with them if a system is designed specifically to handle these smaller payloads.

In assembling Antares launch system with infrastructure, OA chose extremely cost effectively to make a go of it. Few could do better like this. IMHO, they risked too much given how it turned out.

Small market and frugal decisions don't necessarily lead to a viable (or stable) business.

And now you want smaller ... cheaper ... still? You'll get more risk, less viable. Don't you already have your answer?

Offline notsorandom

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Re: Sun Synchronous Medium Launcher
« Reply #31 on: 04/02/2015 07:10 pm »
There are necessary components to every rocket no matter how big or small the rocket. Some of them can't really be scaled much. Avionics for example will generally be cheaper per kg of payload if the rocket carries more payload. Though the overall rocket is typically cheaper there is a pretty well established trend in price per kg being higher the smaller the rocket's capacity. I suspect that there is a point where this really starts hurting smaller rockets.

Offline edkyle99

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Re: Sun Synchronous Medium Launcher
« Reply #32 on: 04/03/2015 03:56 pm »
In assembling Antares launch system with infrastructure, OA chose extremely cost effectively to make a go of it. Few could do better like this. IMHO, they risked too much given how it turned out.

Small market and frugal decisions don't necessarily lead to a viable (or stable) business.

And now you want smaller ... cheaper ... still? You'll get more risk, less viable. Don't you already have your answer?
Antares doesn't fit the market I envision.  It is too big - able to lift more than 4 tonnes to sun synchronous orbit - its design driven by ISS requirements.  (Give me a rocket with only one NK-33 or RD-19x engine.  Give me a small, maybe even mobile launcher rather than the big, complex Wallops Antares infrastructure.)

Last year, 25 of the world's 92 orbital launch attempts were made by rockets only capable of lifting 3 tonnes or less to sun synchronous LEO.  Only one of those 25 was from the U.S. (a Delta 2-7320).    Other countries have even recently developed new rockets of this class (Kuaizhou, Vega, Epsilon), while the U.S. has phased out its capabilities (Atlas E, Titan 23G and soon Delta 2) - which led to the ridiculous examples of Atlas 5 launching 1.2 tonne DMSP and 2.8 tonne Worldview 3 and Falcon 9 v1.1 putting up 600 kg Cassiope and 1 tonne Orbcomm in recent months.  Even one of China's new CZ-5 series rockets is designed for smaller payloads.  What does the rest of the world know that the U.S. seems to ignore?

 - Ed Kyle
« Last Edit: 04/03/2015 04:02 pm by edkyle99 »

Offline arachnitect

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Re: Sun Synchronous Medium Launcher
« Reply #33 on: 04/03/2015 06:09 pm »
In assembling Antares launch system with infrastructure, OA chose extremely cost effectively to make a go of it. Few could do better like this. IMHO, they risked too much given how it turned out.

Small market and frugal decisions don't necessarily lead to a viable (or stable) business.

And now you want smaller ... cheaper ... still? You'll get more risk, less viable. Don't you already have your answer?
Antares doesn't fit the market I envision.  It is too big - able to lift more than 4 tonnes to sun synchronous orbit - its design driven by ISS requirements.  (Give me a rocket with only one NK-33 or RD-19x engine.  Give me a small, maybe even mobile launcher rather than the big, complex Wallops Antares infrastructure.)

Last year, 25 of the world's 92 orbital launch attempts were made by rockets only capable of lifting 3 tonnes or less to sun synchronous LEO.  Only one of those 25 was from the U.S. (a Delta 2-7320).    Other countries have even recently developed new rockets of this class (Kuaizhou, Vega, Epsilon), while the U.S. has phased out its capabilities (Atlas E, Titan 23G and soon Delta 2) - which led to the ridiculous examples of Atlas 5 launching 1.2 tonne DMSP and 2.8 tonne Worldview 3 and Falcon 9 v1.1 putting up 600 kg Cassiope and 1 tonne Orbcomm in recent months.  Even one of China's new CZ-5 series rockets is designed for smaller payloads.  What does the rest of the world know that the U.S. seems to ignore?

 - Ed Kyle

The economics of small rockets in the US is weird. Maybe it has something to do with high labor and infrastructure costs? I'm puzzled, for example, at the renewed infatuation with air-launch in the very small "market." I'll bet building and maintaining a launch site in the US costs much more than in other countries. Without a good launch cadence, fixed costs just destroy the business case for a new rocket.

Atlas E/F and Titan 23G weren't so much "retired" as used up. There aren't any more surplus liquid ICBM boosters in the US. Orbital and Lockheed are offering systems made from clusters of ICBM solids, both surplus and derived.

Looking again at the old DMSP/Tiros satellites after seeing this post http://forum.nasaspaceflight.com/index.php?topic=37129.msg1350535#msg1350535 I see that not only were they smaller than JPSS (who knows what the DMSP successor will look like), but they also did the launch vehicles a huge favor by carrying a big chunk of dV onboard in the form of the ISS/Star-37. They don't build them like they used to: we're building bigger, more capable, longer-lived satellites rather than launching frequently. USAF was launching DMSP constantly and they still had coverage gaps.

Spacex is the obvious company to do what you've proposed, they have good propulsion options for 1st and 2nd stages. For now they're trying to build reusable rockets though; we'll see if it works or not.

I don't think ULA is interested in starting another vehicle family right now. They had plenty of opportunities to restart Delta II but they probably can't even sell the last one.

If Alaska keeps subsidizing KLC, Athena could come back from the dead.

OrbitalATK brackets this payload class with Antares and Minotaur. They could build something on top of 3.7m solids, but really they'd only be competing with themselves. The less said about Stratolunch the better.

Who's left? Blue Origin? SNC decides to get into the LV business? Virgin Galactic?

Okay how about a 1 BE-4 first stage (bolt on roll control) 2nd stage is an "undersized" storable bi-propellant stage (preferably non-toxic to simplify ground handling). Vehicle is built up on the pad with a really austere MST (like Wallops 0B). Maybe I'll run some numbers and see if it pencils out at all...

Online GreenShrike

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Re: Sun Synchronous Medium Launcher
« Reply #34 on: 04/04/2015 03:58 am »
Other countries have even recently developed new rockets of this class (Kuaizhou, Vega, Epsilon)

How much does it cost to fly on an Epsilon or Vega launcher? Wikipedia says around US$32M and €32M respectively, with development budgets of >$200M and €710M. And how much does it cost to fly on JAXA and ESA medium/heavy launchers?  It would be stupidly wasteful to put a 500kg SSO sat on an H2A or Ariane 5. Even an ESA Soyuz isn't so cheap as to have anyone want to use one to lift such a light payload.

By avoiding the cost of heavy launcher, a half dozen or so national launches will see the lighter rockets pay for themselves. Any commercial sales thereafter are gravy. The sheer savings of having a light launcher available for national use probably galvanized their respective governments to finance the launchers' developments. 

What does the rest of the world know that the U.S. seems to ignore?

Which is why I think it's more "have" than "know". They have the development money.

The US government is busy developing SLS, and they're even penny-pinching commercial crew to get it done. So the government doesn't have any spare cash to throw at a small launcher. But do they really need one? Isn't the Minotaur 4-6 series of rockets available and in the right range for throw weight? How's Minotaur-C doing on the civilian side of the market? I don't think its flown yet.

Large US aerospace companies themselves seem to be loathe to spend their own money developing hardware absent a development contract. ATK said they'd build Liberty even if they didn't get into CCiCap, right? Is Lockheed Martin's Athena III a real rocket, or a set of blueprints waiting on a sale to begin production? And who's going to buy the first launch except at a discount? And if the rocket is discounted, who's paying for the R&D? Who's going to roll the dice on a few hundred million dollar bet with shareholders to answer to?

Small US aerospace companies don't have the money for the development of even a light launcher, unless they have a billionaire financing them. Two out of the three of those have a primary goal of Mars, and if they build small, it'll only be as a stepping stone.

Maybe Blue Origin will build their own Falcon 1, but Jeff Bezos has a lot more money than Elon Musk did, so they can start higher up the food chain and not worry about commercializing their experimental vehicle(s).

SpaceX thinks they can get Falcon 9 flights down to some ridiculously low price. Even if they can just manage a mildly silly one, they'll be around the same price with their reusable medium as an expendable light launcher. Oh, and with a F9's lift capability, maybe the sat builder doesn't have to sweat bullets and dollars trimming the sat design down to a svelte single tonne; maybe they can make it a bulky but cheap 2-3 tonnes, and toss in an extra propellant tank for good measure. At any rate, SpaceX believes they already have a launcher that can compete for light SSO launches, so they're not going to spend the engineering time on a smaller rocket.

As for the third company, I'll admit that I really don't see how Stratolaunch is going to compete, but I'm not Paul Allen, so I also don't have to worry about it and can just sit back and hope to see it fly someday. If it doesn't, I'm not going to be stuck with a Roc-shaped hole in my wallet.

So who's left that can finance a new launcher? In a class restricted to around what's apparently a quarter of available launches? Against a half dozen flying vehicles in the same class? *And* who thinks betting against SpaceX succeeding at their goals is at all safe?

Not, I think, the US government, and not large public companies, but possibly smaller companies funded as a billionaire's hobby project. But I doubt it.
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Offline Space Ghost 1962

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Re: Sun Synchronous Medium Launcher
« Reply #35 on: 04/04/2015 07:25 pm »
Small market and frugal decisions don't necessarily lead to a viable (or stable) business.
(Give me a rocket with only one NK-33 or RD-19x engine.  Give me a small, maybe even mobile launcher rather than the big, complex Wallops Antares infrastructure.)
Fear you miss my point. A light Delta II / Soyuz 2.1v as "commercial" economics may be unsupportable.

Quote
Last year, 25 of the world's 92 orbital launch attempts were made by rockets only capable of lifting 3 tonnes or less to sun synchronous LEO.  Only one of those 25 was from the U.S. (a Delta 2-7320).
Agreed about market opportunity. Suggest it is "inaccessible" in America.

Quote

Other countries have even recently developed new rockets of this class (Kuaizhou, Vega, Epsilon), while the U.S. has phased out its capabilities (Atlas E, Titan 23G and soon Delta 2)
Delta came from Thor IRBM. Atlas/Titan ICBM. Leveraged development/existing pad. Vega leverages Ariane/other base. Epsilon attempts to evade high H2 development costs for consolidation.

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... - which led to the ridiculous examples of Atlas 5 launching 1.2 tonne DMSP and 2.8 tonne Worldview 3 and Falcon 9 v1.1 putting up 600 kg Cassiope and 1 tonne Orbcomm in recent months.
Paid for by not developing EELV/F9 "lite" versions.

Quote
...  Even one of China's new CZ-5 series rockets is designed for smaller payloads.  What does the rest of the world know that the U.S. seems to ignore?
There are limits to LEGO/"dial a rocket" architectures. China, Russia, India, ... do not have American industrial base.

The economics of small rockets in the US is weird.
What is different is national policy and industrial support for it.

Funding of "soft power" with a HLV is not for free, especially in America. Nor is a nat sec "launch monopoly" to specifically address a narrow need/cadence/100% reliability demand. OA/SX live in the "remainder" economy.

Quote
Maybe it has something to do with high labor and infrastructure costs? I'm puzzled, for example, at the renewed infatuation with air-launch in the very small "market." I'll bet building and maintaining a launch site in the US costs much more than in other countries. Without a good launch cadence, fixed costs just destroy the business case for a new rocket.

Stratolaunch/BO are "big ego plays". Firefly is a speculation to "cling on" to niche market need.  Super Strypi attempts to probe the bottom of the cost/technology of launch - cheap pad/LV/ops for responsive launch. VG is funded too poorly and has other conflicting goals to expect much.

Quote
... They don't build them like they used to: we're building bigger, more capable, longer-lived satellites rather than launching frequently.
... In other words, excess launch capacity translated into the need for DMSP living longer without the restrictions of payload.

Quote
Spacex is the obvious company to do what you've proposed, they have good propulsion options for 1st and 2nd stages. For now they're trying to build reusable rockets though; we'll see if it works or not.

To accomplish SX mission, they have a disincentive to serve this need with another LV.

The incentive to address Ed's OP is with reusable launch frequency where primary cost is propellant and a fraction of a LV.

Quote
I don't think ULA is interested in starting another vehicle family right now. They had plenty of opportunities to restart Delta II but they probably can't even sell the last one.
ULA's replacement of Delta II was EELV Lite. Never happened - end of story for ULA.

Quote
If Alaska keeps subsidizing KLC, Athena could come back from the dead.
KLC has been on the edge for most of its existence. The total cost of SSO launch is why Athena has not come back - current launch market is "too cheap" ironically for much interest. Too much risk in "volume" not happening.

... By avoiding the cost of heavy launcher, a half dozen or so national launches will see the lighter rockets pay for themselves. Any commercial sales thereafter are gravy. The sheer savings of having a light launcher available for national use probably galvanized their respective governments to finance the launchers' developments. 
Variation on subsidy. "Gap minimizer". And, given Soyuz ST, unpredictable "payoff".

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What does the rest of the world know that the U.S. seems to ignore?

Which is why I think it's more "have" than "know". They have the development money.

The US government is busy developing SLS, and they're even penny-pinching commercial crew to get it done. So the government doesn't have any spare cash to throw at a small launcher. But do they really need one? Isn't the Minotaur 4-6 series of rockets available and in the right range for throw weight? How's Minotaur-C doing on the civilian side of the market? I don't think its flown yet.

Because the market isn't able to support it with reliable cost/volume of launch.

Quote
Large US aerospace companies themselves seem to be loathe to spend their own money developing hardware absent a development contract. ATK said they'd build Liberty even if they didn't get into CCiCap, right? Is Lockheed Martin's Athena III a real rocket, or a set of blueprints waiting on a sale to begin production? And who's going to buy the first launch except at a discount? And if the rocket is discounted, who's paying for the R&D? Who's going to roll the dice on a few hundred million dollar bet with shareholders to answer to?
Its not the first launch, it is a reliable manifest with enough frequency. One needs a constant payoff.

And, like with Antares and KLC, launch failures set you back a year or so - need to fund this.

Also, even with billion dollar programs involving multibillion mega firms like LockMart and Boeing, you can be reticent to "play". Atlas V program did everything to minimally address EELV to minimize downside risk - they didn't even want to play, but had to be "encouraged" to do so.

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So who's left that can finance a new launcher? In a class restricted to around what's apparently a quarter of available launches? Against a half dozen flying vehicles in the same class? *And* who thinks betting against SpaceX succeeding at their goals is at all safe?

What one is up against is few parts, market fragmentation, lack of repeatability in demand, and the potential for launch costs dropping and launch frequency rising. Not attractive to finance because too many ways to lose.

RD-190/3 et al limited to non defense launches - hmm, there goes an important segment. And the negative propensity for further downside risk from future potential "risks".

AJ/SX engines? Available? If not a F9/Antares "compatible", where would you launch?

Conceivably, the best possibility is a single engine Antares or a three engined F9, each with a "tank shrink". Your costs are smallest, you can qualify for flight easiest, and the same components/systems/GSE would be used in the same way.

Falcon Lite. Antares Lite. "Less filling, tastes great" ;)

Offline arachnitect

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Re: Sun Synchronous Medium Launcher
« Reply #36 on: 04/05/2015 09:43 pm »
I've been playing around with rockets built on top of a single BE-4. I'm just using a simple rocket equation spreadsheet, so to say my methods are crude is an understatement.

My original idea of a 1x BE-4 stage with a Delta II upper stage on top was a bit of a disappointment. Something like the Ariane 5 EPS does better, but is probably far too little thrust. Something like Agena lies in between, with the same problem of low thrust.

Centaur or a similar stage powered by BE-3(U) have very good performance, but again I have no idea what the gravity losses are like (bad, I suspect). Also now we're dealing with LH2.

Strapping 4x Falcon 1 second stages together makes a nice 2nd stage for this rocket. Yet again, gravity losses may be in play. I don't expect Blue Origin and Spacex engines to end up on the same rocket, but I use it as a model of a pressure fed hydrocarbon stage.

Looking at RD-0110/RD-0124 it quickly becomes obvious why Orbital was pursuing it. These engines offer good performance, relatively high thrust and without the hassle of LH2. There are some other Russian options, but these would probably be the best choice.

What we have available in the US is very good LH2 stages and lots of solid motors (i.e. missile parts). What we don't have is a relatively cheap and simple pump-fed hydrocarbon or storable fuel engine in the 300 kN range.

Online LouScheffer

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Re: Sun Synchronous Medium Launcher
« Reply #37 on: 04/08/2015 07:21 pm »
Modern versions have gotten heavier, up to 2.5 tonnes or so, but are still small payloads on an Atlas 5 or Delta 4 or Falcon 9 v1.1, which are overkill since they can lift 7-8 tonnes to sun synchronous orbit.  [...]

I wondered what could be done with liquid stages and other bits and pieces.

If SpaceX wanted to get serious about this, they could just put a low-cost second stage on top of their existing Falcon-9 first stage (which will be cheap if re-use works as they hope).   Make it short and fat, so they can build it on their existing equipment, and revive the Kestrel engine, which is pressure-fed and should be cheap.  ISP is not great (~317) but more fuel is a simple workaround when you've got an oversized first stage anyway.

This should be as cheap to develop and cheap to fly as any competitor.  Same tooling, same fuels, same ground infrastructure, already flown engine, an existing (overkill) fairing, especially if they can recover it.  The first stage already exists and has high production volumes and a fast cadence.  Any rocket is going to expend the second stage, and theirs can be super cheap, since it has no need for unobtainium since the first stage has more lift than they need.  No need for fancy alloys, maybe don't even isogrid the tanks.  A crude analysis shows that even with a rotten mass fraction of 10 (25 tonnes of fuel, 2.5 tons empty) and the (cheap) kestrel, they could loft 2.5 tons or so.

I, for one, would not want to try competing with this.

Offline Space Ghost 1962

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Re: Sun Synchronous Medium Launcher
« Reply #38 on: 04/08/2015 08:03 pm »
Economics work better to keep US the same as possible, and because you change stage 1, make all your changes there.

So stage 1 is "undersized", stages earlier/lower/slower (reuse?) and stage 2 does the rest of the work.

US economics of design far more difficult to "change manage" and certain economics of function are "baked in".

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