Idea Delta Glider Zero

[Tacolev]

Discussions of "realistic" delta-gliders have tended to focus on what would be required to make a functioning SSTO spaceplane with similar capabilities, size and performance characteristics. These have been fruitless for a variety of reasons.

But there is another way to make a "realistic" delta-glider: one that still masses around 25 tons and has realistic OMS-only main engines, with no hovers or retros or scrams. While no longer an SSTO spaceplane, it would still be within LEO payload capacities for a variety of national and commercial carrier rockets, and could take advantage of the numerous addons made for putting DGs into orbit like N_Molson's national DG_Launchers series. It would be capable of fulfilling a variety of missions like space station resupply and crew rotation. The most one might ask out of it is a trip to the moon via L1 fuel depot, followed by LOI and docking at a lunar orbiting station.

More importantly, this would still embody what the DG represents to a lot of people--A production spaceplane with routinized and standardized operation like a commercial aircraft. Basically everything the space shuttle wasn't. The aesthetic of that is more important than one might think, as it evokes a whole, complete picture of human spaceflight as a real institution with its own infrastructure and conventions as such.

Or it could just be the spacecraft3 config file with realistic values I slapped together before posting this...

 

[N_Molson]

Of course, I completely share your vision of a "DG-R", which would be a small shuttle (but not a mini-shuttle).

The XR1 allows you to set your own parameters ; that's currently my favorite option. I'd love to see a version without hovers, retros or scrams, though.

 

[T.Neo]

That is no longer any DeltaGlider, it is now just a variation on Hermes, HL-20, Prometheus, heck, even the X-20 to an extent. It is just a payload on a rocket and no matter how hard you try to make it its own commercially viable package or whatever, it will still be just that: a payload on a rocket.

Even my 50+ meter long, 100 ton (impossible!) SSTO is more of a DeltaGlider, than a winged payload on a rocket.

 

[N_Molson]

That is no longer any DeltaGlider, it is now just a variation on Hermes, HL-20, Prometheus, heck, even the X-20 to an extent.

So the Space Shuttle is a payload (that carries a payload) ? :uhh:

 

[T.Neo]

No. Here's the difference: Hermes, is lofted on a booster. That booster can be used for X amount of other payloads. It isn't dedicated to Hermes.

With the shuttle, on the other hand, the orbiter is an essential part of the stack, as it contains the engines. While you have the boosters as an effective first stage, you can begin to regard the ET as just a drop tank to the Orbiter, after SRB separation.

 

[Tacolev]

Indeed, that's precisely the idea.

There are only two ways with present or near-future tech to build a spaceplane as big as the DG.

One way is something like the Starclipper or the original shuttle design or MAKS with its own engines and a drop-tank.

The other way is the litany of examples you've provided. They are "just" payloads on rockets and that is a realistic near future spaceplane because of:

-Lower development costs
-Bigger performance and engineering margins
-Best optimistic representation of near-term human spaceflight.

Let's face it, in the near future the scene is still going to be dominated by national space agencies but there will be more and more commercialization and crosstalk with private entities. Imagine this as a COTS entry. Joyrides-for-millionaires LLC can buy a spaceplane and stick it on a Falcon booster or Nasa can stick it on a Delta IV heavy or The Very Big corporation of America can stick it on a Delta IV Heavy or Roskosmos can stick it on a proton.

Then, thirty years later KulchCo can stick it on the TX a few times before the next production run.

The ability to fit in with a variety of architectures and suggest a unified face as they evolve and change is the other thing the DG is, if not a feasible SSTO spaceplane.

 

[T.Neo]

What does STS or a rocket payload have to do with a DeltaGlider? A DeltaGlider is supposed to be a compact, high performance, practical vehicle. While it may not make much sense for locations outside LEO, a compact practical vehicle still makes sense to launch personnel and payload into LEO.

The shuttle is most definitely not compact, nor is it practical. Something like Starclipper is maybe slightly more so, but a spaceplane on a rocket fails the definition entirely.

And it fails not because of the spaceplane, which would be pretty easy to do and might be pretty easy to operate. It is because of the whole huge rocket underneath it, that needs to be thrown away each time it launches.

 

[N_Molson]

And it fails not because of the spaceplane, which would be pretty easy to do and might be pretty easy to operate. It is because of the whole huge rocket underneath it, that needs to be thrown away each time it launches.

Is the SLS really that cheap ? Were not speaking about sending 120 tons to LEO, but 25 tons...

 

[T.Neo]

Of course not. But the cost/kg does not go down with the total payload mass. At Proton rates, roughly $4300, it would cost 107 550 000 to lift 25 tons to LEO...

And all the other technical requirements of such a launcher severely limit the adaptability of the system, which is really supposed to be the forte of the DG.

 

[Hlynkacg]

And it fails not because of the spaceplane, which would be pretty easy to do and might be pretty easy to operate. It is because of the whole huge rocket underneath it, that needs to be thrown away each time it launches.

What if you used a reusable booster and only gave your spaceplane enough dv for orbital insertion/return?

 

[T.Neo]

Then you have a payload that is launched on a winged reusable sub-orbital booster, rather than an expendable multistage booster.

 

[Hlynkacg]

Then you have a payload that is launched on a winged reusable sub-orbital booster, rather than an expendable multistage booster.

would that still be a "failure"?

 

[Sky Captain]

would that still be a "failure"?

Depends how much maintanance is required after each flight. If the booster can fly like 10 or more times without major overhaul then it would make sense. If it is like shuttle that needs army of technicians to take it apart and put back together after each mission then expandable rockets would be more cost effective.

 

[T.Neo]

More cost effective, but still very costly.

Even a Hermes-like spaceplane would not be a failure, even though there are reasons for which it wouldn't make as much sense in such a role as a capsule could. It just wouldn't be much of a DG in anything other than rough dimensions...

 

[Sky Captain]

Something similar in size and function to DG would be possible to build only if miniaturised aneutronic fusion reactors are developed. Fission powered engines are just too massive to fit on so small airframe and chemical fuels lack the energy density to allow so small spaceplane to go to orbit.

 

[Ghostrider]

Something similar in size and function to DG would be possible to build only if miniaturised aneutronic fusion reactors are developed.

Do you mean Minovsky-Ionesco ultracompact He-3 based fusion reactors? Would be cool, but say goodbye to your radars, IR detectors/imagers and long range communications.

 

[T.Neo]

Just because you don't have neutrons, doesn't mean you don't have any ionising radiation at all. You can still for example have X-ray radiation.

The DG still can't carry its fuel mass in terms of LH2, for example. Already you need to be bigger if you want to carry that as propellant. And an engine with the performance of that on the DG would still have to be larger than those portrayed even if the technology could be miniturised, due to physics and materials constraints.

Another issue is that practically the only fusion thrust design I can find that has a TW of over 1, is ICF fusion, like on Daedalus. I'm not too sure about pulsed thrust, though I suppose if the frequency is high enough you reduce the problems of resonance and crew annoyance.

But getting it to work on a spaceplane? I dunno, it sounds wrong to me.

Then again I know as much about fusion reactors as a baboon knows about a loaded firearm. :dry:

 

[Sky Captain]

Do you mean Minovsky-Ionesco ultracompact He-3 based fusion reactors? Would be cool, but say goodbye to your radars, IR detectors/imagers and long range communications.

Yeah, something like that. You basically must have an engine that is about as big and massive as engines found on jet fighters and have ISP of over 15 000 m/s when using dense propellant.

 

[Ghostrider]

Just because you don't have neutrons, doesn't mean you don't have any ionising radiation at all. You can still for example have X-ray radiation.

I know, just pulling your Zaku's leg.
It was a reference to Mobile Suit Gundam, in UC tech Minovsky-Ionesco reactors generate Minovsky particles which interact with EM radiation making radar and IR useless so you're back to visual range combat.

 

[N_Molson]

... or you can do evil things, like cross-breeding a Space Shuttle SSME with an honest DeltaGlider... :lol:

With some modifications on the rear fuselage, and a shield/flap beneath the nozzle, it fits well in.

Edit : it would, of course, require an external tank and SRBs