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Post Info TOPIC: "New" NASA plan...


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"New" NASA plan...


NASA readies Plan B for moon rockets
Side-mount shuttle with no winged orbiters may save billions of dollars
By Irene Klotz
Discovery Channel
June 24, 2009

090624-shuttle-hmed-3p.widec.jpg

NASA has a backup plan to launch crew and cargo to the moon, reduce the gap between shuttle retirement and a replacement ship's debut, and save taxpayers billions of dollars.

They call it the side-mount shuttle. It's basically the space shuttle system without the winged orbiters.

Preliminary NASA studies show that using the existing shuttle's solid rocket boosters, fuel tank and main engines as a launch system, with some minor modifications, could be the foundation of an alternative to the planned Ares rocket program currently under development.

NASA plans to retire the shuttle fleet after the international space station construction is finished, currently targeted for September 2010. Engineers have been working on a new system that not only could transport astronauts to the station, which orbits about 225 miles (360 kilometers) above Earth, but also travel in deep space for visits to the moon and other destinations.

Ares remains on track for a 2015 debut flight to the space station, at a cost of about $35 billion, program manager Jeff Hanley explained last week before a presidential panel reviewing the country's human space program.

For somewhere in the neighborhood of about $6.6 billion, NASA can develop a rocket for the moon.

Shuttle program manager John Shannon, who presented an overview of the side-mount shuttle launch vehicle to the same committee, cautioned that the cost is very preliminary, though it is the same figure derived by a NASA-commissioned team that studied a similar vehicle design three years ago.

Shannon says the shuttle-based heavy lifter is not as capable as Ares V, the rocket currently earmarked for a revived lunar exploration initiative that is intended to land astronauts on the moon by 2020. The side-mount shuttle's lunar lander would have to shrink from the planned 48 metric tons to about 28 metric tons.

"That's still pretty good because the Apollo lunar lander was 16 metric tons," shuttle program manager John Shannon said in an interview with Discovery News.

The side-mount shuttle system would be able to launch astronauts to the station or the moon inside Orion capsules, which also are being developed under NASA's Constellation program.

The capsules would sit inside a protective shroud that could fly the spacecraft away from the rocket in case of an accident. NASA used a similar escape system on its Apollo capsules and is developing one for Orion. Russian and Chinese crewed spaceships also have launch escape systems.

The side-mount shuttle would be simplified to cut costs and increase its lift capability. The shuttle's three hydrogen-fueled main engines, for example, would be not be reused, as they are today. The engines, along with the external tank and solid rocket motors, would be dropped into the ocean during the climb to orbit. Under the current configuration, the shuttle's main engines are attached to the tails of the orbiters, which make piloted runway landings.

"Reusability is a myth, in my opinion," Shannon said, citing the cost of maintaining manufacturing capability, production of single replacement parts and the need for post-flight inspection and engineering assessments.

A few new pieces of equipment would be needed to transition the shuttle into a new launch vehicle, including development of a payload fairing to protect cargo during launch, and a structure to bolt the main engines on to the fuel tank. It would use the same four-part solid-fuel booster rockets used today, with an upgraded five-segment system envisioned for future heavier-lift vehicles.

Among the key advantages of the side-mount shuttle is that the flight software, launch facilities, manufacturing capability and 30 years of test flight history are already in hand.

"The benefits are obvious. We basically have the parts to build everything," Shannon said.

The alternative NASA rocket could be ready for testing in about four and a half years at an estimated cost of about $2.6 billion.

More on NASA | Project Constellation

URL: http://www.msnbc.msn.com/id/31532912/ns/technology_and_science-space/

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This concept is literally "Shuttle-C" and represents, I think, about the most costly option...even though it requires almost no modification of existing pad and processing infrastructure...

There was even a full scale mockup of Shuttle-C:



interesting set of pictures of a full scale mockup:
http://www.collectspace.com/ubb/Forum30/HTML/000769.html

Here is  link to a paper describing the Shuttle-C concept:

http://images.spaceref.com/news/2009/shuttlecexec.pdf

Basically the orbiter is replaced with a main-propulsion system package that includes OMS pods and contains three SSME's. However, it is all expendible--so I really don't see the point of going this route. You take the most expensive components of the STS, and then use them only once on a mass inefficient, extra fancy payload fairing.
That's my take on shuttle-C.


-- Edited by GoogleNaut on Monday 29th of June 2009 08:57:44 PM

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Basically the orbiter is replaced with a main-propulsion system package that includes OMS pods and contains three SSME's. However, it is all expendible--so I really don't see the point of going this route. You take the most expensive components of the STS, and then use them only once on a mass inefficient, extra fancy payload fairing.
That's my take on shuttle-C.


As the quote from the article says, "reusability is a myth".
It's never worked out to be effective to reuse the SSMEs. They're high performance and costly just for that, but a lot of the cost is the extra complexity involved in making them reusable. Make them one-use (or better yet, use another engine if the SSME is too expensive in any case) and the cost per launch goes down because of less processing time to ready for a launch -not to mention it's not man-rated, so between one-shot and no crew, the cost drops to a fraction of that to launch the components as a regular STS flight.
Aa big thing that can't be overlooked is the entire infrastructure for stacking it and handling it on the pad is what's there. Beyond the vehicle, rebuilding all of that would (will) be a big part of the cost of the "in-iine" "Ares V" vehicle.

The bonus is that even if you're not using the SSMEs and get less payload per fuel use because of that, you're still putting up more payload than the STS ever did.
"Mass inefficient": you say? it's more efficient than the STS because you're not lifting crew capabilities or any of the bells & whistles for landing them. ~80% of the mass to LEO of the STS is such "dead mass". The Shuttle itself is the only thing "extra fancy" about the current stack. Get rid of it, and lots of our problems go away with it.
 Pure dumb cargo cannister. How more cargo-mass-efficient can you get?

The flying cost-overrun that is the airplane Shuttle is the killer. Remove it immediately, and costs drop.
 It's assinine to design to put crew up on this. Go with SpaceX or an Atlas or Titan Heavy or the Arianne V man-rated for crew (preferably with the HL-20).

-- Edited by john fraz on Tuesday 30th of June 2009 01:31:37 AM

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http://newpapyrusmagazine.blogspot.com/2009/06/ares-alternative-part-2-john-shannons.html

Long video of Shannon talking about it.
Lots of answers.

Not Shuttle-C, because one big difference is that there's no "separation plane" between the tank and the payload & motors. They don't eject on-orbit or recover. Drop 'em into the ocean with the ET.
(I've always said this is the best option, and I've seen it elsewhere, so even this isn't something NASA has just invented.)

He repeats that reusability is a myth (at least the SSMEs.) Lots simpler & cheaper to just dump 'em.

It also addresses the fact that it's derived from the STS via the Shuttle-C, and that has been looked at for a long time.

(edited with embed, if it works)

<object width="400" height="300"><param name="allowfullscreen" value="true" /><param name="allowscriptaccess" value="always" /><param name="movie" value="http://vimeo.com/moogaloop.swf?clip_id=5340181&amp;server=vimeo.com&amp;show_title=1&amp;show_byline=1&amp;show_portrait=0&amp;color=&amp;fullscreen=1" /><embed src="http://vimeo.com/moogaloop.swf?clip_id=5340181&amp;server=vimeo.com&amp;show_title=1&amp;show_byline=1&amp;show_portrait=0&amp;color=&amp;fullscreen=1" type="application/x-shockwave-flash" allowfullscreen="true" allowscriptaccess="always" width="400" height="300"></embed></object><p><a href="http://vimeo.com/5340181">U.S. Human Space Flight Committee-Washington, DC Part 7</a> from <a href="http://vimeo.com/user1955131">U.S. HSF Committee</a> on <a href="http://vimeo.com">Vimeo</a>.</p>


-- Edited by john fraz on Thursday 2nd of July 2009 02:07:43 AM

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"A devotee of Truth may not do anything in deference to convention. He must always hold himself open to correction, and whenever he discovers himself to be wrong he must confess it at all costs and atone for it." Monhandas K. Gandhi


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The main advantage of this is that it's not a "Bush" plan.  Because according to Obama everything Bush is bad.  Now what exactly was Bush doing?  So Team Obama has to redo everything. 

I have no doubt that the Shuttle should have been retired by now because it should have been replaced by a next generation system.  Probably one that includes an combined cycle propulsion system.  It also need a better thermal protection system. 

The problem with existing NASA plans is that it a giant step into the past...Basically Apollo Redux.  This is not real progress.  The main issue with the Shuttle is false advertising.  At the scale it was operating it was mail a research program than a mature space transportation system.  We are never going to have reusable spacecraft if we don't fly any.  At first of course it would have been cheaper to do it some other way but one needs to fully understand the problems so that solutions can be developed.

Even existing Shuttle would be more economical per flight if we had a much larger scale of operations.  Only four vehicles at such low sortie rates leave one with a massive fixed cost.  Consider where the economies of the 747 would be if we only had four of the first five constructed and we fly then only a few times per year.  To make reusability viable we need next generation designs and much higher activity levels.


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I have talked with a couple of engineers (one of whom actually works out there on the Cape) that the threshold where reusability becomes economical is just about 40-50 flights per year. This indicates to me that a scale of operations ten times larger than what we currently possess is necessary for it to become economically viable. This means that we would need an "assembly line of facilities" and processes to bring everything together, as well as a fleet of vehicles possibly as many as fifty in number.

This would then become a major industrial operation...

Look at the scale of what the major airlines do--everything is done in a big way to move millions of passengers per year.

The magic threshold of 40-50 flights per year seems to jive with the original claims (circa 1976) of the fledgeling shuttle program. However, I think few anticipated the level of safety problems that have since occured...and that's why it is a test project.

The shuttle never really did become 'Operational.'


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