News: Space Launch System

[FlyTexas]

The latest and greatest from NASA. Looks kinda familar.

http://www.nasa.gov/multimedia/videogal ... =111389911

Brian

[DarrenL]

Looks like an Ariane 5 to me.

[Garry Russell]

Ther's only a limited way a rocket system can look

[Chris Trott]

More in common with the Saturn IV-B to me than the Ariane. The SRB's attached are the extended models that were originally destined for Constellation, so there's nothing new there. The upper stage is all Constellation, including the Orion crew module, so again, nothing's new there. They actually managed to almost fully re-use the work of Constellation, something that most space enthusiasts and professionals were concerned they wouldn't do. Add to all that, the first stage will be using the high-performance SSME's that were just rolled out for the last dozen shuttle flights to power that stage, the biggest time consumption will be building the test articles and then integration of the systems, allowing them to keep a timeline that's only a couple years delayed to what Constellation was going to be while handing off servicing of ISS to the private sector which should be able to do it at a better cost (and so far looks to be well on its way to doing so).

[fran65]

...to me the "rocket system" is a step back from the space shuttle system,.....my little opinion, of course....
Why not the ISS as a launch base? If I remember correctly one of the purposes of the ISS is to be as launch base for deep space missions ...or not?

[Chris Trott]

While a "step back" in some ways, the system using a capsule allows for maximum flexibility and was always the preferred method for going forward with planetary manned exploration because you are not restricted in the payload dimensions like you were with the Shuttle. The Shuttle was always a "dead end" in that it was solely supposed to be used to support Low Earth Orbit operations, originally to be SkyLab and then Space Station Alpha, which is now ISS. However, ISS was always designed to only have about a 20 year lifetime. Budget delays and the slowing of launches after the Columbia accident extended the build out of the station quite a bit meaning that almost half of its useful life has already been taken up. As such, ISS will never be a "launching off" point for anything more than the experiments performed on it. The "jumping off" point was actually supposed to be the Moon. I've not seen if this is still a plan, but the idea with returning to the moon was not only to prepare for Mars, but also to establish a base where the rocket for the Mars trip could be assembled and launched with a much lower fuel cost due to the lower gravity.

[SkippyBing]

...to me the "rocket system" is a step back from the space shuttle system,

Put it this way any rocket system can only launch so much mass into space. If you're using the Space Shuttle a large portion of that mass is taken up with the actual shuttle, reducing what you can leave up there or as Chris says at best limiting its dimensions. With a more retro launch system you can leave all the mass up there.

As an aside the Shuttle design was optimised for a USAF requirement to be able to launch and recover in one orbit for potentially nefarious activities*, this required the large wing for atmospheric manoeuvring. This meant it was sub-optimal for NASA's requirements as a portion of the launch mass is taken up by wing area that's not needed. Handily the USAF then dropped out and the ability was never used.

*Pop up and grab someone's satellite when they can't see, that sort of thing...

[Chris Trott]

Well... you don't know if it was used. There were 10 DOD-only missions we know of and no one has talked about them, so we don't know what went up and what came back, only that there was a launch. There have also been reports that one of the orbiters *DID* launch from Vandenberg on a DOD mission, but it's never been included in the offical tally and there is no good intelligence to back up the claims.

The DOD flights were -

STS-3 (listed as a "R&D" flight, much of the flight was blacked out to the public)
STS-4 (confirmed launch on a DOD mission with a DOD payload, no word as to what that payload was for sure, but supposedly included 2 launch detection satellites)
STS-51C (unconfirmed launch of a Magnum-class satellite for the NSA, but nothing more)
STS-51J (possible launch of a DSCS satellite)
STS-27 (likely Lacross satellite deployment)
STS-28 (likely SDS satellite deployment)
STS-33 (likely Magnum again)
STS-36 (likely Misty recon sat)
STS-38 (possibly SDS satellite, but not confirmed)
STS-39 (first unclassified DOD mission, no launches)
STS-44 (confirmed DSP satellite deployment)
STS-53 (last DOD mission, partially classified, no confirmation on payload)

So, of those, there is the chance that something was caught and retrieved as most of the DOD missions were almost completely blacked-out using military comm frequencies and frequency hopping equipment (HAVE QUICK) that prevented monitoring from the ground amateur stations that usually tracked STS missions during any communication that referenced the payload and operations. We do know that the shuttle did return at least a dozen civilian satellites over the years in addition to several long duration free-floating experiments that were launched by one mission and picked up by the next. So the abilities of the Shuttle were well utilized, including that ability to retrieve and return satellites.

[SkippyBing]

Chris, the USAF/DoD specific bit was the cross track ability confered by the wings, basically this allowed the Shuttle to reposition during re-entry so it could make the continental US after launch. i.e. take off enter space and land in a single trip round the Earth, without the cross track ability the orbiter would end up somewhere else due to the Earth's rotation, I'd have to look up the exact details when I'm near a real computer but it basically meant you could launch and recover the Shuttle without the USSR being able to track it. It'd be interesting to know if that capability was utilised, rather than just the ability to recover satellittes which has dual applications.

[jonesey2k]

We really need an SSTO system like the Reaction Engines Skylon design.