Short answer: no, you cannot build a DeltaGlider.
The main reason centers on the propulsion system. The engines just put out
way too much thrust at
far too high an exhaust velocity for their size. While certain fusion engines, for example, could match this thrust, they would have to be 10-30 times the size portrayed.
Several other engine concepts could match this performance too, such as a open gas core nuclear thermal rocket, or a nuclear salt water rocket. Both of these would be very environmentally unsound, as they would release radioactive waste into the environment (though the gas core probably less so). These engines would probably also be larger and more massive than portrayed in the DeltaGlider.
Heat dissapation from the nozzles is also a problem. The heat encountered by the engine would likely vapourise it very quickly. This is why fusion engines use magnetic nozzles, instead of physical ones; thrust is contained by a magnetic field, and heat escapes through the framework. A magnetic field can't melt or vaporise.
Engines that dump waste heat into the exhaust, however, like a GCNR or NSWR could possibly get away with physical nozzles.
Something often said of the Deltaglider's engines is that they would "vaporise the spaceport" or "leave a kilometer wide crater". I personally find this hard to believe. Without any calculations on the destructiveness of the engines, I'd bet that the destruction would be far smaller in scale.
Solid calculations on the destructiveness of high performance engines seem to be mostly missing, despite it being brought up in things like
Jon's Law and the
Kzinti Lesson. Nevertheless, if the engines are spewing radioactive waste- or
still fissioning uranium salts, the physical destruction caused by the engines would pail into insignificance compared to the ecological damage.
I also find some of the other aspects of the DeltaGlider's design shaky. It supposedly carries 12900 kg of fuel in the main tanks. If the propellant was slushed hydrogen, it would need 151.7 cubic meters. If it were water, it would need 12.9 cubic meters. I doubt that it would be able to accomodate the former within the main body, but the latter should be accomodated easily. Wing tanks could potentially provide more volume, but installing insulation and cooling throughout the wing would be troublesome. The available volume in the main body would drop if a portion of it were taken up by a cargo bay, for example.
That doesn't even cover things like the TPS. Presumably such a vehicle would be covered in ceramic tiles and thermal blankets.
The long answer; :lol:
A 5 person orbital spaceplane to be lifted on a conventional launch vehicle- or more remotely an airbreathing vehicle, is very possible (there have even been small spaceplane projects such as HERMES). The only main thrusters the craft would posess would be some sort of OMS.
A nuclear powered SSTO shuttle with surprising performance might also be possible, though it would require plenty of development and PR. Presumably a more environmentally friendly engine; such as a closed gas core design or a solid core NTR would be used. The craft will be undoubtedly larger than the DG, mostly due to the fact that it will actually have to carry propellant. Nevertheless it would have a greatly reduced mass fraction compared to a chemical SSTO.
There are also regions where the DG has been designed for gameplay rather than engineering reality. The frontal docking port and airlock would probably be merged with the top hatch, for example. Retro engines have no use; them and their doors just add mass. If hovers were absolutely vital, the rear engine nozzles could be gimballed to save the extra mass and complexity of rear hover engines. The radiator on the DG is probably also far too small. The rear RCS would have to be redesigned as to not damage the rear vertical stabilisers.
The only way I can see a delta-glider being built for 'real' is to have a wood mock up in the back garden.
I agree- it would be pretty awesome, too.
That, or an RC model like RisingFury's. :thumbup:
