No joy in Mudville (or at Kennedy Space Center)

GregGleason said:

I like these (but I'm "old school").

The rocket that is second from the right looks like it could lift a Nimitz-class carrier.

from: https://www.astronautix.com/fam/saturnv.htm

Greg

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luke strawwalker said:

Yer WELCOME skyspike...

Agree with Bob on most of this, but there's a couple things I'd mod...

If you're talking about an "off the shelf" Sat V v.2.0 then yeah, you're limited to pretty much the RD-180 (two chambers) or RD-170 (four chambers) motors (RD-180 is used on Atlas V-- not sure if we even have the license to get/use/mfg. RD-170's). The other alternative is the AJ-26 used on the Orbital Science Corps. new Taurus II LV. The NK-33 was designed for the Soviet N-1 moon rocket, and it's got the highest thrust/weight of any rocket engine ever built, among its other fine attributes, which is why OSC wanted it for their Taurus II. Problem is NK-33's only produce about 338,000 lbs of thrust at liftoff, so they'd require large clusters, so that pretty much eliminates them for an HLV first stage, just like Merlin 1C/D. That pretty much leaves you with the RD-180/170...

A better solution would probably be to finish the TR-107. At 1.1m lbs thrust, it's a modern-day replacement for F-1. I don't have the specs on the ISP, but it's likely to be better than F-1. A cluster of five of these would be a straight "drop in" replacement for F-1's on a Saturn V type vehicle.

As the "safety numbers" require keeping the separation/staging events and engine count down, I'd go with a monolithic first stage based on the ET diameter, to reuse the same tooling and fixtures to the extent possible and cut costs. Kerosene is much denser and therefore requires a much smaller fuel tank than the hydrogen tank in the ET, so even feeding five large kerolox engines, the first stage itself should be about the size of a shuttle ET. The conical LOX tank would have to go, but that's being planned for in every "shuttle derived" rocket anyway. The LOX tank would be larger, but the kerosene tank would be much smaller than the present ET hydrogen tank. I'd feed the engines with external LOX lines like the present ET uses rather than the "tunnel thru the kerosene tank" ala Saturn S-IC. Using a monolithic stage consisting of a stacked pair of propellant tanks and intertank like the current ET (and the S-IC for that matter) gives sufficiently good mass fraction (which isn't AS important on the first stage as upper stages) while making construction easier/cheaper.

The second stage would be ET diameter and use either a pair of SSME's or a single RS-68. Problem is, either one would require significant development, and I'm not sure an RS-68 can even be airstarted. SSME was found to be 'feasible' to airstart, but would require a development program to accomplish, and that costs a lot of money. J-2X OTOH is already "paid for" and well under way, but it's lower thrust rating means you'll need 4 or 5 to do the job. So basically you'd have to re-create the S-II stage... the S-II was a good stage once it's teething problems were fixed-- of course nobody had ever tried building a common bulkhead tank that size before, which was part of the problem, but it should be fairly straightforward today. Sticking to the 8.4 meter ET size rather than the 10 meter S-IC/S-II size of Saturn V keeps the tooling common. J-2X's are thirsty, so the stage would be quite a bit longer than the S-II, especially when you figure in the smaller diameter...

The third stage would be 8.4 meter ET diameter as well, and would be powered by a cluster of 6 RL-10's. These engines have superior ISP and are light in weight, and would do quite nicely for the EDS TLI burn duties; much better than the lower ISP J-2X. RL-10 is an "off the shelf" and highly reliable engine, one which will undoubtedly be the base for whatever cryogenic in-space propulsion needs arise for landers and such (like the Altair lunar lander descent stage, or the DTAL lander). The CECE engine is an RL-10 variant under development for just such applications, so manrating RL-10 and its variants should be fairly straightforward.

This rocket would be about the same height as Saturn V, perhaps somewhat taller... keeping the EDS stage diameter at 8.4 meters helps keep the height down and make up for the taller second stage. Problem is, this only gets you to about Saturn V performance-- the lunar missions proposed need a lot more payload than a single-launch Saturn V could provide. BUT, going to a dual-launch type system using a pair of these Saturn V v.2.0's would work nicely, and increase the flight rates to amortize the infrastructure costs. There isn't going to be a 'cheap' way to do lunar or Mars missions, so we need to stop pretending there will be (at least in OUR lifetimes). This rocket would also service LEO needs if called upon to do it-- perhaps an "INT-20" version of the first and third stage for simple LEO missions not requiring heavy cargoes, or an "INT-21" version of the first and second stage for lofting 8.4 meter payloads to LEO for Mars vehicle construction if/when needed. A hammerhead to a 10 meter fairing would be easily doable if needed for greater payload volume.

There is something to be said for scrapping the 8.4 meter tooling and switching everything back to 10 meter tooling for all three stages. BUT it would involve a lot of extra costs, but it would also allow for easier upgrading later on, if and when the desire was there to do so.

For cargo-only versions, provisions for adding strap-on boosters, either as Atlas V cores for LRB's or GEMs from the Atlas V or Delta IV would be a good option to have to loft heavier payloads, and wouldn't require a lot of work to "scar" the booster for them in the original design phase.

If SpaceX ever came out with their Merlin 2 engines, these might be a good upgrade, as they're higher thrust IIRC.

There are a lot of proposals floating around... some are quite interesting. I've followed the "DIRECT" proposal for years over on nasaspaceflight.com/forums and been impressed by it, but now I'm seeing more and more the enormous costs of keeping SRB's around, and I think it's a poor trade.

Later! OL JR

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bobkrech said:

My comments were intended to show what could be done with extant motors, or one's ready to fly.

All modern liquids are Russian designs whether anyone wants to admit it or not. The last American liquid was the SSME because for some reason we were convinced that solids were more powerful, cheaper and safer, but the Russians kept plugging away on liquids and make more reliable and less expensive liquid motors.

The TR-107 was a RD-180 class equivalent, not an F-1, and since we already make the RD-180, the TR-107 is redundant. The only existant F-1 equivalent is the RD-170/171. We don't have a licensing agreement but as we have one with the RD-180 it shouldn't be hard to get one.

Any LV based on Shuttle technology is, or should be, DOA. It is obsolete, expensive, unreliable without expensive maintainance 1970's technology, and doesn't compare to the current LVs performance or cost.

The SpaceX Falcon 9 is the dark horse, but it will win the race. It a modern Soyuz type launch vehicle with multiple inexpensive but proven motors. The Soyuz launcher is the most reliable and most used LV of all times. I predict the Falcon 9 and it's varients will eventually compete well with it.

No fuel is better for a volksrocket than LOX/Kerosene. It cheap and easy to handle. You use diesel in a volksbus, so why not in a volksrocket. I can't find a single reason not to.

The Altas V and the Falcon 9 are equivalent EELVs that use LOX/Kerosene. The 9 Merlin 1-C motors in the Falcon 9 are equivalent to the 1 RD-180 in the Atlas V. The Falcon 9 Heavy with 27 Merlin 1-C motors and scheduled to be flown in 2014, would be equivalent to the proposed Atlas 5 Heavy (which is not being persued) with 3 RD-180 motors. The Delta IV heavy is much more expensive to buy operate, but due to the law of conservation of bureacuracy, that the plan...

If the US had chosen the Atlas V Heavy over the Delta 4 Heavy years ago, the US would be there now. They didn't, so IMO, ULA's days are numbered, and the practical, low-cost upstart SpaceX will have the US commercial launch market captured within this decade because of ther low-cost, high-reliability, plain vanilla volksrocket.

After all, it's only a bus...

Bob

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Daddyisabar said:

Wow, is it just me or do some of these machines remind you of outlandish proposals made to save a collapsing Reich and to keep the engineers making them from receiving a one way ticket to the Eastern Front. Like Sargent Schultz on Hogan’s Heroes “I know nothing!”

Again, upon seeing some of these proposals the NKVD guy inside of me just wants to get a list of names, smack the smartest one in the mouth and send him to the Gulag! That will surely get some results. How can you tell me the Fascists can build these rockets with slave labor when all we can do is barely make Comrade Stalin’s Organ work...? AAhhh…the good old days!

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Downix said:

Well, if the smartest one is the guy who cooked up AJAX, that would be yours truly. Was hunting for a diagram and ran across this place. Thanks for sharing there Luke.

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