Liquid fueled alternatives to the Ares I solids.

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exoscientist":36ug09ub said:
Here's another source suggesting the Augustine panel is recommending against Ares I:

Augustine Panel takes final options to White House staff.
posted by Robert Block on Aug 14, 2009 11:44:48 AM
"The Constellation program in all of its guises is presumed to have scored very low, a sign that NASA’s work for the last four years on the Ares I and Ares V rockets and the Orion crew capsule may be stillborn.
"According to panel insiders, until yesterday committee members were working hard to make option 5b -- the flexible deep space option to explore the solar system using an EELV -- fit more closely to the budget. This option would likely relay on a rocket with a liquid oxygen and kerosene engine that would be designed and operated by a commercial company and bought by NASA." ... staff.html

Interesting they seem to be saying the preferred option is an EELV using LOX/kero. That could mean the Atlas V, but that uses the RD-180, a Russian engine. The "designed and operated by a commercial company" part doesn't necessarily mean an American company but it certainly implies it.
Again this could mean restarting the RS-84. But if you use a RS-84 on an EELV that would be extremely wasteful because it was designed to be reusable.
I thought another possibility for the "designed and operated by a commercial company" LOX/kero rocket mentioned could be the Falcon 9.
However, I just looked up some info on the Falcon 9:

Falcon 9.

It uses 9 Merlin engines of only 125,000 sea level thrust. I find it unlikely that NASA would want to use a cluster of 9 engines for its manned launches. Creating a version of nearly 10 times greater thrust is also not merely a matter of scaling. It nearly requires an entire new design. That would be quite expensive and time consuming. I find it unlikely NASA would assign that gargantuan task to SpaceX.
SpaceX also intends to makes these engines be reusable by sea recovery. I found it even more unlikely NASA would trust delicately balanced, high thrust engines used on manned launches to undergo sea recovery. High pressure turbopumps with their quite exacting tolerances used on such engines are something very different that just solid rocket motor casings.
That leaves us again with the RS-84 or the TR107 engines that have already udergone partial development. And again if these reusable engines are used it would be extremely wasteful not to use flyback boosters to reuse them.

Bob Clark


exoscientist":2sy1w3zv said:
I find it unlikely that NASA would want to use a cluster of 9 engines for its manned launches.
What is wrong with clustered engines? Saturn used those.


exoscientist":1w6r6v57 said:
It uses 9 Merlin engines of only 125,000 sea level thrust. I find it unlikely that NASA would want to use a cluster of 9 engines for its manned launches
The Falcon 9 Heavy will use 27 Merlin 1 engines! :shock:

SpaceX is also working on the Merlin 2, which is much more powerful than the Merlin 1. Ultimately, the proof of the pudding will be in the tasting -- If SpaceX can demonstrate the reliability of the Falcon 9, then whether it uses 9 engines or one big @ss engine shouldn't matter.


exoscientist":1i7oqxjd said:
This article from 2002 stated the development costs for two heavy thrust liquid fueled prototyoes would cost $1.3 billion:

"Potential replacements for the Space Shuttle
are taking shape as NASA struggles to finalise
the requirements for a second-generation
reusable launch vehicle."
"Engine development"
"The success of our architecture depends
on the success of NASA's engine development
programme," says Young. The space
agency is funding work on four main
engine candidates, two hydrogen fuelled
and two kerosene-fuelled. Pratt &
Whitney and Aerojet are developing
the Cobra, a 600,0001b-thrust (2,670kN)
hydrogen-fuelled, staged-combustion, firstand
second-stage engine, while Boeing's
Rocketdyne division is working on the
650,0001b thrust-class RS-83. Rocketdyne
is also pursuing the RS-84, a kerosene fuelled,
staged-combustion, first-stage
engine generating 1,100,0001b thrust,
while TRW is developing the 1,000,0001b
thrust-class TR107.
The plan is to test two prototype
engines at a cost of $1.3 billion. "NASA will
go for prototype engines that bracket the
requirements of the three contractors,"
says Ford. He suggests the emphasis has
shifted towards the kerosene-fuelled
engines. "NASA wants to address kerosene
first to reduce risk," he says. The USA has
little experience with kerosene-burning
rocket motors, having focused for decades
on cryogenic engines." - 2996.html
Then if NASA chose to develop one of these, such as the RS-84, to save costs, it conceivable might only cost $650 million (!)
Then since the Air Force also wants a heavy thrust LOX/kero engine for its flyback booster program, the cost to NASA if the costs were shared might only be $325 million. NASA would only have to spend $108 million per year over 3 years to develop a reusable heavy thrust engine(!!)

My opinion, NASA needs to restart development of the RS-84 with all deliberate speed.

Bob Clark


exoscientist":3ufmuux3 said:
Then if NASA chose to develop one of these, such as the RS-84, to save costs, it conceivable might only cost $650 million (!)
Then since the Air Force also wants a heavy thrust LOX/kero engine for its flyback booster program, the cost to NASA if the costs were shared might only be $325 million. NASA would only have to spend $108 million per year over 3 years to develop a reusable heavy thrust engine(!!)

My opinion, NASA needs to restart development of the RS-84 with all deliberate speed.
X-43C, RS-84 Engine Among Casualties Of NASA Review.
Mar 19, 2004
By Jefferson Morris ... g03194.xml

When NASA cancelled the hypersonic X-43C and the reusable RS-84 meant for flyback boosters back in March, 2004 it undoubtedly seemed then these were far off technologies not in keeping with the Bush administration's request for near term Moon and Mars missions.
However, the Air Force in ground tests has recently successfully demonstrated hypersonic airbreathing propulsion. The success of these tests in hypersonic wind tunnels simulating real conditions gives confidence the flight tests later this year will also be successful.
Flyback boosters for two stage to orbit vehicles undoubtedly also seemed an expensive, complex proposition then. But Scaled Composites with SpaceShipOne proved, later that very same year, that as long as the flight speed is kept in the Mach 3 range to limit reentry heating, these can be developed quickly and cheaply.
The use of either of these would result in significant cuts to the costs to space. It now appears they would be the route to low cost and quick return to space that NASA wants in the wake of the shuttle retirement. And indeed their implementation could lead to the manned missions to the Moon that are desired within 10 years and in keeping with NASA's budget.
Since the Air Force already wants these and NASA needs them, I recommend a return to the costs-sharing plan intended for them under the Next Generation Launch Technology program.
The development costs for the RS-84 reusable engine needed for the heavy lift flyback boosters might be only ca. $100 million/yr over 3 years IF those costs were shared with the Air Force.
This report gives the Air Force space budget only as close to $12 billion in 2009:

FY 09 Air Force Space Budget: Modest Increase. ... =index.cfm

I don't think there would be much hue and cry from Congress about a less than 1% change especially when it's known this small amount would solve the Ares I problem, which is a huge headache for NASA right now. That 1% of the Air Force's space budget wouldn't even have to come from an increase. The Air Force could shuffle some lower priority projects to a later period to cover it.
You can think of it as altruistic of one governmental agency to another in trouble. Or you can think of if it as good business men do of an investment that will pay for itself several times over in the future. The Air Force wants this heavy lift thruster, though several years down the road. By helping NASA pay for it now they are cutting the costs in half of what they would have had to pay for it all by themselves at probably an even higher total cost with inflation.
Note too this applies to the flyback airframes for NASA's new launchers, since the Air Force intends to use this method on all their future launchers. For their smaller satellite launchers, some projections put this as being operational by 2018 for the Air Force. Then by splitting the cost with NASA on the airframe development, they cut their costs in half and can get an earlier deployment date since NASA needs it as soon as possible. Altruism and your own bests interests sometimes go hand in hand.
The President if he really wanted to could force this. Sometimes leaders, like parents, have to make their charges make the right decisions even if at the time they don't have the good sense to make it themselves.

Bob Clark


I find it amusingly ironic that this Congress, and the previous ones, would argue over such a tiny increase at the same time they're spending our kids into bankruptcy for other things totally unrelated to keeping our non-IT high tech jobs or pursuing science and exploration off-planet.

The 'H' word fits, I think.


Regarding the cost to send a human into space:

Russia Soyuz: $51 million
Shuttle: $105 million
Ares+Orion: $361 million

Now it isn't fair to compare apples to oranges because the Ares+Orion costs include the development costs and the fact that it is part of a larger vision. But these numbers do help illustrate why building something new that is only going to be used infrequently can result in huge costs.

These numbers come from NASA's Human Space Flight page's questions and answers:
NASA":3uozznz5 said:
Q: I've heard that it costs $51 million to put a U.S. astronaut in space in a Russian capsule. How much does it cost for a Space Shuttle seat, and how much will it cost for a seat on the new Orion capsule once it is available?

A: Correct, NASA will be paying $51M per seat on the Soyuz spacecraft starting in 2012. It is important to remember that this $51M pays for more than just the transportation including training, lodging, and the stay at ISS among others. Unfortunately, this number cannot be directly compared to the Shuttle and Orion per seat cost because it does not include all the fixed cost that come along with supporting a full Program. Having said that, the average cost per Shuttle seat is approximately $105M in today’s dollars. This rate per seat assumes 4 flights per year at 7 astronauts per flight. A one Shuttle flight increase would decrease this rate by about 20%. The new Orion Crew Exploration Vehicle is currently slated to fly 2 flights a year with 4 astronauts per flight. At this rate, the expected cost will be approximately $361M per seat in today’s dollars. When comparing these numbers, please keep in mind that the Constellation Program is developing spacecraft capable of reaching the moon, while the other seats only go to ISS.


exoscientist":14kn7lk1 said:
Then if NASA chose to develop one of these, such as the RS-84, to save costs, it conceivable might only cost $650 million (!)
Then since the Air Force also wants a heavy thrust LOX/kero engine for its flyback booster program, the cost to NASA if the costs were shared might only be $325 million. NASA would only have to spend $108 million per year over 3 years to develop a reusable heavy thrust engine(!!)
This article by Henry Spencer reminds me that the Air Force cleverly has the ability to resurrect launch programs previously cancelled by Congress:

Failure to launch: abandoned NASA projects.
"National Launch System (NLS); 1989 – 1993; perhaps $300 million.
"This was a joint NASA-US Air Force project for a low-cost shuttle-derived expendable launcher to replace existing expendable rockets, such as Atlas, Delta and Titan launchers."
"After some fumbling, the US Air Force replaced it with the Evolved Expendable Launch Vehicle (EELV) programme that produced the Delta IV and Atlas V rockets. (The RS-68 engine that powers the Delta IV is probably derived from work on the "Space Transportation Main Engine" for the National Launch System.)" ... projects/4

The RS-68 developed by Rocketdyne is a heavy thrust liquid hydrogen engine that powers the Delta IV Heavy. Its development cost only $500 million, it took only 5 years, and it had operational flights within only 1 year (!) after development concluded:

Boeing Completes Checks For Latest Delta IV Maiden Flight Date
Defense Daily, Oct 31, 2002 ... n28953910/

This gives confidence that the RS-84 also by Rocketdyne could indeed be developed for $650 million, so only $325 million to NASA under cost-sharing with the Air Force, and perhaps have a full scale prototype model ready by 2012 if restarted this year.

The Air Force appears to have resurrected another cancelled program with the "Reusable Booster Program." This is essentially the same thing as its ARES (Affordable REsponsive Spacelift) system that was cancelled by Congress in 2006:

Ares FBB.
"Winged orbital launch vehicle. Family: Winged. Country: USA. Status: Development.
The ARES ((Affordable REsponsive Spacelift) concept was of a reusable fly-back booster with expendable upper stages. The US Air Force began development of a demonstrator in May 2005, with a first flight date of 2010. It was felt that derivatives of the concept could support all space lift requirements of the USAF."

So following the Air Force's lead, to restart the RS-84 and flyback boosters NASA just needs to call it under a different name than the "Next Generation Launch Technology" program.

Bob Clark ;-)


There are still plenty of the F1 engines still around. Why not reverse engineer them, and add what newer improvements in such areas as electronics as can now be done. As for man-rating, they were certainly good enough to get us to the moon the first time around, so I do not see why they should be any different now!

Besides, using these totally American developed and made engines gets us away from the export problems of using Russian hardware!

And there are still enough of the original people working at Rocketdyne to make this happen for a whole lot less than continuing the current design of the Ares I, let alone the future Ares V!

Heck, NASA originally had plans for even larger rockets than the venerable Saturn V. Remember the NOVA?

IF NASA is allowed to go through with the Ares V, it will be far too heavy for the transporters and the tracks from the VAB to the launch complexes anyway, and this will necessitate literally tens of billions of dollars extra in costs. Even a rocket as large as the then proposed NOVA would still be well within the weight limits, as the empty weight of a liquid engined rocket is far less than the weight of a solid rocket on its way to the launch pad!

Besides which, while liquid engines are indeed far more complex than solids, they do have an advantage that actually still makes them far safer. That is that when you test a solid rocket motor, it is gone, and can not be retrieved as the same motor for the actual production launch vehicle. This necessitates that solids MUST have EXACTLY the same consistency and chemical make up EVERY time they are used. The slightest discrepancy, and KABOOM! Now, ATK has indeed done a very admirable job in doing this through such Quality Assurance methodologies as Statistical Process Control, no doubt about that, but.....

But, with a liquid rocket engine the very same engine that is tested, can then still be used as the actual production launch vehicle engine! IN fact, every such liquid engine manufactured by Rocketdyne is given a "Green Run" of at least 60 seconds. If all of the parameters of the engines operation run in the "Green" the engine is then accepted as an actual production engine! For instance there has NEVER been a launch failure of the RS27A sustainer engines for the Delta II. Which is one reason that NASA still uses this thirty year old design for its highly important robotic space probes. Such probes have enough problems without getting into space at all do to an engine failure!

As for the SSME, it is far and away the most heavily pre tested rocket engine on this planet! Know wonder there has never been a failure of such an engine that caused a mission failure (although there were some problems with some sensors, that were not originally a part of the engines themselves), and as there are three such engines for every shuttle launch, that is quite a record for reliability and safety!

Hopefully, the Augustine Panel will recommend an entire scrapping of the current Constellation project, and come up with a far less expensive and safer all liquid engined manner of going back to the moon!

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