New Shuttle, Let's dust off Venture Star!

[EarthlingX]

Can somebody explain the business model behind a "reusable" space vehicle? Reusability denotes a destination and right now there is no destination in space (The ISS is only going to be around for about 10 years). If you're talking about point to point from NY to Tokyo that's one thing but if you are going into deep space you need to deal with orbital speeds to re-enter Earth and for that you can't beat the design of a capsule. Wings in space makes as much sense as a one armed man clapping.

Airliners are an example of reusable craft that hints on business model. Destination is everywhere, LEO is first step, L-s next, NEO-s, Moon, heliosphere.
You can bleed your orbital speed above atmosphere, if you have fuel to burn, than go in slow and easy, no heat.
If you get in atmosphere at some couple of mach, you can glide in, parachute in, use rocket powered landing like new Russian post-Soyuz capsule; you could probably even use some lighter than air tricks. No need for such heavy heat shield and you have a better controlled descent.

There will be of course less ELVs sold, if that is bad for business but i think it's possible there will be actually more sold.
Check this design for Angara reusable boosters:
http://www.russianspaceweb.com/baikal.html

Here is a big table comparing various RLV designs:
http://www.hobbyspace.com/Links/RLV/RLVTable.html

 

[EarthlingX]

Another interesting tech, i just recently found about:
(Thrust-Augmented Nozzles for Rocket Engines)
http://www.defensetechbriefs.com/compon ... ticle/4553
http://www.freepatentsonline.com/4327885.html

Tripropellant rocket:
http://en.wikipedia.org/wiki/Tripropellant_rocket
http://www.astronautix.com/engines/rd701.htm

 

[vulture4]

Hey guys, aren't the SpaceX rockets reusable? :?: I saw something on the SpaceX web site about how Musk is disappointed that most people see his rocket as an expendable one, when he intends for it to be reusable.

The rocket was constructed as an ELV but Musk wants to try to recover the first stage to see if refurbishment is practical. Whether the Falcon booster would be reusable would depend on the degree to which salt water can be kept out and how much refurbishment is necessary. If it requires complete disassembly as the SRBs do than reuse is obviously impractical, as it is for the SRBs.

BTW, one of the Mercury-Redstone boosters was found floating in the Atlantic after the launch and recovered by a Navy destroyer. Don't know what became of it, but a steering vane is still on display, I think in the KSC visitor center.

As to the cancellation of the X-33, there are two separate issues that we should clearly distinguish. First, the X-33 was an unmanned suborbital technology demonstrator intended to lead to the Venture Star, which was conceived as SSTO. It's perfectly true that as the program progressed the probability of achieving SSTO faded. That's why the program was canceled. But the X-33 was also a prototype of a fully reusable launch vehicle. As such it would have proven some very important technologies that could have been used in a fully reusable two-stage launch vehicle. It was a misinterpretation by NASA management that SSTO was the only important goal, and that the X-33 was worthless if it couldn't get into orbit. In reality the X-33 was a suborbital demonstrator; it wasn't intended to go into orbit at all, but it would test both the linear spike engine and the new metallic-tile thermal protection system. Reusability itself was much more important than SSTO. The failure of the LH2 tank obviously did not prove composite LH2 tanks are impractical since a tank of exactly that type was demonstrated successfully over multiple flights in the DC-X. The X-33 tank failed because of a poor design intended to integrate it with the lifting-body shape of the vehicle. Ironically the X-33, had it flown, might have helped put to rest NASA's long romance with lifting bodies and demonstrated once and for all the superiority of the wing-and-fuselage design.

Again if anybody knows where Mr. Bekey is now and can persuade him to join the discussion, I would invite him to do so in the spirit of cordial debate, not invective. We really need two-way discussions with NASA management. I would hope those who make the decisions that determine our future would be willing to discuss them with those who have spent entire careers living with their decisions. We both might learn something.

 

[sftommy]

Read a techno study of Venture-Star yesterday.
The X-33s Hydrogen tank problem appears to now have a solution.

The Venture Star would seem to be the next evolutionary step after the shuttle. Too bad the US Heavy Lift effort isn't thinking along this line, but I"m not sure it would meet DoD requirements.

Development cost will keep it back, unless a private contractor or consortium of private contractors can make it happen and then only if they have a place to take paying passengers.

 

[vulture4]

VentureStar itself was a SSTO concept, and with current knowledge SSTO may not be feasible. The X-33 tested several technologies for fully reusable launch vehicles separate from the SSTO concept per se. These included metallic tiles, the linear spike nozzle, and the question of lifting body versus wing-and-fuselage design, as well as autonomous launch and landing. Probably the next tech demonstrator should be a two-stage unmanned reusable suborbital. But several aspects of the X-33 would be critical to such a design.

However I think it is time for the long NASA romance with the lifting body to end. A shape can be a good wing, or a good fuselage, but it can't be both.

 

[Valcan]

Read a techno study of Venture-Star yesterday.
The X-33s Hydrogen tank problem appears to now have a solution.

The Venture Star would seem to be the next evolutionary step after the shuttle. Too bad the US Heavy Lift effort isn't thinking along this line, but I"m not sure it would meet DoD requirements.

Development cost will keep it back, unless a private contractor or consortium of private contractors can make it happen and then only if they have a place to take paying passengers.

Yes but venture star cant get to LEO without a booster can it?

 

[neutrino78x]

Yes but venture star cant get to LEO without a booster can it?

My understanding is that VentureStar was an SSTO, it could go directly to orbit.

Venturestar wikipedia.

I think it was a really awesome idea, some other company should make it, if LockMart won't...

That StarCruiser, from SpaceDev, is similar...it takes off on a EELV but lands like an airplane. Or will, once they build it...

--Brian

 

[Astro_Robert]

VentureStar was supposed to be able to achieve a stable parking orbit to deliver cargo, but not more than that.

Such a thing will probably never be built by a private company unless the government is willing to invest in proving some of the technologies. Lockmart was going to raise some/all of the funds to develop VentureStar after it had proved the technologies with a few launches of X-33. Development of the full scale vehicle would have been several $B and would not have been possible without those results.

As to how economical it would have been, all of that depends upon certain assumptions. Launch rate is #1, Infrastructure cost (including range) is also up there. Maintenance and turn around costs go into recurring costs. Combined with vehicle lifespan, one could determine potential Return on Investment periods for potential investors.

Keep in mind X-33/VentureStar was proceeding at a time when everyone thought satillite phones were going to be ubiquitous and require 40+ commercial launches per year ad infinitum. Between X-33 flight results being unavailable since they did not take place, and commercial flight rates being much reduced when people stcuk with cell phones instead of satellite phones, no commercial investors were going to step up. Since NASA walked away, and the Air Force (for whatever reason you want) never picked up the project either, it sadly isn't going anywhere.

Now, several years down the road, it would probably be almost starting from scratch, as most of the Engineers have since moved on to other projects and even retired. That it never got to fly, was sad; but at this point it would take a miracle for something comparable to happen.