News NASA Delivers Heavy Lift Proposal to Congress

Wally

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NASA told U.S. lawmakers Jan. 10 it intends to build a heavy-lift rocket that incorporates the space shuttle’s main engines, giant external tank and taller versions of the solid-rocket boosters it jettisons on the way to orbit, according to a senior NASA official. However, neither the rocket nor the crew vehicle it would launch could be completed within the cost and schedule Congress outlined for the project late last year.

More on Space News.

---------- Post added at 13:31 ---------- Previous post was at 13:28 ----------

Wouldn't the use of SSME be an overkill in this case? They are expensive and have features that are not necessary for HLV, like the ability to restart or reusability. Why not using RS-68 instead?
 

T.Neo

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SSMEs have a restart capability? I'm 99% sure that they're only able to be started on the pad, they don't have any air start or air restart capability.

I think the major issues with the RS-68 pertain to performance and man-rating the engines. There's some reason- perhaps something economic- that warrants the use of the SSME, but I haven't read through things enough to know why.
 

Urwumpe

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SSMEs have a restart capability? I'm 99% sure that they're only able to be started on the pad, they don't have any air start or air restart capability.

I think the major issues with the RS-68 pertain to performance and man-rating the engines. There's some reason- perhaps something economic- that warrants the use of the SSME, but I haven't read through things enough to know why.

I am 100% sure that the SSMEs can't started anywhere else than from the mobile launch platform.

The problem with the RS-68 is not man-rating, that can be achieved by more testing, but by also getting the performance at the right range. The 250 Ns/kg less specific impulse means a lot of propellant more needed to haul the same payload.

Still, no cigar for NASA. They repetitively produce the same HLV configuration since 1989. Maybe even earlier. Just search for ALS (Advanced Launch System) and the later NLS (National Launch System).

The same phase 0 studies, repeated over and over again, with varying level of detail. The NLS at least entered Phase A once.
 

garyw

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I am 100% sure that the SSMEs can't started anywhere else than from the mobile launch platform.

They can only be started on the ground. The capability for air start or restart would need to be engineered in. If the SSME had a restart capability the early programme RSLS aborts would not have required the SSME's to be removed.

There is a lot of speculation that NASA is playing politics with this as it was congress who mandated reuse of shuttle tech simply to keep the workforce employed (and for senators to keep their seats, laid off workers tend to vote for the other guy in spite). This appears to be NASA pushing back.

Read some of the comments on this posting -> http://nasawatch.com/archives/2011/01/nasa-to-congres.html

Also, Congress have just told NASA 'Do it our way' -> http://nasawatch.com/archives/2011/01/full-text-of-na.html

"We appreciate NASA's report and look forward to the additional material that was required but not submitted. In the meantime, the production of a heavy-lift rocket and capsule is not optional. It's the law. NASA must use its decades of space know-how and billions of dollars in previous investments to come up with a concept that works. We believe it can be done affordably and efficiently - and, it must be a priority."
This puts NASA in a difficult spot. They know Congress plans are foolhardy, they know that the HLV is being built just because congress say it can rather than with any specific mission in mind yet they are being told to do it because it's the law.

And people wonder why NASA have a hard time doing things........
 
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Urwumpe

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And people wonder why NASA have a hard time doing things........

Sometimes you can just kick all congressmen and women into the mud, and let a squeaky voice from the past explain them:

Never tell people how to do things. Tell them what to do, and they will surprise you with their ingenuity.

I sometimes wish to ask some of these in public, since when they are aerospace engineers, and why they think they are better qualified in deciding which rocket brings the USA advantages.

Any rocket that is actually build is better than a rocket that is only designed over and over again for keeping people employed, that otherwise serve no purpose any more. As hard as it sounds: You do the USA, ATK or Boeing employees no favor that way.

Not even the companies. They get a large amount of pork barrel, that is right. But they have to keep a lot of employees allocated on producing things, that are impossible to be sold somewhere else.
 

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I sometimes wish to ask some of these in public, since when they are aerospace engineers, and why they think they are better qualified in deciding which rocket brings the USA advantages.

That is so, because NASA has no domestic competitors. The very idea behind a governmental space agency assumes that key decisions in its running are politically motivated and carried out by politicians.
 

Urwumpe

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That is so, because NASA has no domestic competitors. The very idea behind a governmental space agency assumes that key decisions in its running are politically motivated and carried out by politicians.

But that is so stupid. Politicians should set the goals, not the solutions. They should say "bring us to this moon", and NASA should say "If you give us that much money, we can get you there in a few months, but for a fraction of the money, we can research if a cheaper way exists."

This way, the USA simply waste money for keeping people employed. Which is so much communism, that the international should be played at all times in the US Congress.
 

GoForPDI

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I would assume the SSME's used (or RS-25's as we should be calling them now) will not be exactly like the Shuttle ones, they would obviously have Shuttle-only features removed (like reusability etc)
 

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Wait, so is this the Jupiter-Direct launch platform that was being developed as an alternative to the Ares-1? Or am I misunderstanding what they are proposing?
 

GoForPDI

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Think of it this way:

Shuttle ET (8.4m diameter) with two 5 Segment SRB's strapped to each side and RS-25's (SSME's) on the bottom of the ET. Above the ET you have an upper stage powered by a J-2X.

Similar to DIRECT, yet at the same time makes use of the 5-seg SRB's and J-2X developed for Constellation.
 

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SSME are the most efficient (first stage) engines ever developped. Their ISP range of 363s/453s is unmatched. They are complex and expensive, but that's the kind of technology we should not let forget in oblivion. They are the best of the best, and that would be a pity to design a HLV without them.

From Wikipedia :
A leading goal of the RS-68 program was to produce a simple engine that would be cost-effective when jettisoned after a single launch. To achieve this, the RS-68 has 80% fewer parts than the multi-launch Space Shuttle main engine (SSME). Simplicity came at the cost of lower thrust-efficiency versus the SSME: the RS-68's thrust-to-weight ratio is significantly lower and the RS-68's specific impulse is 10% lower. The benefit of the RS-68 is its reduced construction cost: To build an RS-68 for the Boeing Delta IV program costs about $14 million, compared to $50 million for the SSME.
 

C3PO

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The vehicle must be able to initially lift 70-100 tons to LEO, and must be evolvable to 130 tons or more.

The vehicle must be able to lift a MPCV

The vehicle must be capable of serving as a backup system for supplying and supporting cargo and crew delivery requirements for the International Space Station (ISS) in the event such requirements are not met by available commercial or partner-supplied vehicles.

A 100 tons craft to service the ISS? :facepalm:
IMOH not the cheapest way to do it.
 

T.Neo

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No, a 100 ton service craft is the way to go, really... that way you can launch a payload that's almost an entire third the station's total mass! :facepalm:

At least they'll never, ever need to resupply the ISS again... :lol:

Also, what is an MPCV? Why does Congress want to launch outmoded Rhodesian combat vehicles into orbit? :huh:
 

N_Molson

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Exactly, with 3 launches, you can build another ISS. Makes the station building much easier (even better, the components can be pre-assembled & ready to power on).

Also, having a reliable, ready-to-launch HLV could be useful in the perspective of a lunar base or a Mars mission.
 

C3PO

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Why does Congress want to launch outmoded Rhodesian combat vehicles into orbit? :huh:

Ballast probably. Without it the acceleration will be too much for the crew. :rofl:
 

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(my mass margin calculation abilities are not among the best) Could also serve to launch a death star to a GEO spot at the longitude of Pyongyang...
 

C3PO

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Exactly, with 3 launches, you can build another ISS. Makes the station building much easier (even better, the components can be pre-assembled & ready to power on).

Also, having a reliable, ready-to-launch HLV could be useful in the perspective of a lunar base or a Mars mission.

Why would you want a new station for every 3 crews?
And servicing ISS with a craft built for Mars is going to very expensive.
 
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