So it's a viable buisness idea then, and the military would be interested in possible funding? let alone NASA. R and D costs could be about a Billion tops, then each indivicual unit would be about a billion or so to build. Expensive but realitivly not too bad.

As to a viable business project and military interest, do a search for ATG Skycat and WALRUS.

The technology is already done, the engines were made in prototype i nthe 60s, but stopped evelopement on them becasue they were too politicly contriversail. Only R and D would be incrasing egine effiacny then designing the dropship.

One draw back is due to the immense weight of the dropship, it can only land and take off in certain palces without the landing legs getting to stuck in the ground.

So here is some more information. What i need from you guys is wether or not this concept would be viable in military operations.

 

SOo first off here is some info on the engins and the ship desgin. Ship design is roughly spheroid, about 18-220meters high, 190-250meters wide at it's widest point. So this things massive. Gross weight is aobut 30,000 tons.

 

Here is some ifnormation on similar designed engines.

 

"In this section I describe a huge nuclear powered rocket launcher. I will repeat and expand upon many of the points I made above, because I don't want to throw cryptic acronyms around. I want people to understand just how powerful we can make this rocket if we decide to do it.

The effective use of nuclear power in space transportation allows a paradigm shift in our thinking. All boosters which have been built to date have been shackled by the low efficiency of chemical fuels. Using chemicals it is possible to get off earth, but only barely. Every gram of structure must be trimmed, exotic materials and cutting-edge techniques are a necessity, and safety margins must be as slim as we dare if success is to be achieved.

Nuclear power changes all that. Nuclear is VASTLY more energetic than chemical. We no longer must guard every gram of mass. Much more "margin" can be included. Much more safety can be designed into the machine.

Let's examine a large heavy lift booster. There are other kinds of nuclear rockets we could build, but we desperately need a heavy lift booster if we are to excite people, catch their dreams, and actually do big stuff in space.


For an engine, I will designate a Gaseous Core Nuclear Reactor design, of the Nuclear Lightbulb subvariant. I like the gas core design for a number of reasons, and the nuclear lightbulb variant for several more.

To recap, the efficiency and power of the thruster is based on the difference in temperature between the fissioning mass and the reaction mass. If you run a solid core NTR much above 3000 C, it melts. This provides a firm "ceiling" on how efficient a solid core reactor can be. A gas core design STARTS melted. In addition, since all of the structure of the fuel mass is dynamic, a gas cored reactor is inherently safer than a solid core device. If a "hot spot" develops in a solid core, disaster ensues. If a hot spot develops in a gas core, the hot spot superheats and "puffs" itself out of existence. A gas core reactor is expected to operate at temperatures of 25,000C. The much higher temperature gradient makes the thruster inherently more efficient.

Second, a solid core reactor has a "fixed" core, since it is solid. A gas core reactor does not, and the radioactive fuel is easily "sucked" out of the core and stored in a highly non-critical state completely out of the engine! The fuel storage system I propose is a mass of thick walled boron-aluminum alloy tubing. As I said above, the fuel proper is uranium hexaflouride gas. UF6 is mean stuff, but we have decades of experience handling it in gaseous diffusion plants, and common aluminum and standard seals are available which resist attack from it. It is stoichiometric, fluorine is low activation, and UF6 changes phase at moderate temperatures, allowing it to be converted from high pressure gas to a solid and back again using nothing fancier than gas cooling and electrical heaters. This naturally makes dealing with the engine easier.

In addition, the design of the gas core allows the addition and removal of fuel "on the fly." The core can also have its density varied by control of the vortex, which directly affects criticality. Both of these elements allow very potent control inputs to be applied to a gas core reactor which are very stable and unaffected by the isotopic condition of the fuel mass.

Also, to repeat, due to the extremely high temperature gradient in the motor, the main cooling of the fissioning mass is not conductive but radiative, a mode which is inherently less susceptible to perturbations. (Having no working fluid for cooling means no material characteristics for the working fluid must be considered.) This radiative cooling mechanism is what allows the "lightbulb" system to work. The silica bulb just has to be transparent enough to let the gigantic power output of the fissioning core flow through, while keeping the radioactive material of the core safely contained inside the thruster. No radioactive materials leak out of the exhaust, it is completely "clean."

Third, a gas cored reactor has several potential "scram" modes, both fast and slow, and the speed of the reaction is easily "throttled" by adding and removing fuel or by manipulating the vortex. A 'scram' is an emergency shutdown, usually done in a very fast way. For example: a gas cored reactor can be fast scrammed by using a pressurized "shotgun" behind a weak window.

can't see the benefit in it.

 

only useful if you have absolute intra-theatre dominance - otherwise it will require disproportionate effort to protect it while in and out bound.

The safety implications are gargantuan. The environmental considerations are massive. On top of this, you need to design and build your vehicle to withstand loads that aren't defined, since we haven't built anything like this before. You would need several sub-scale demonstrators to prove concepts and cooperation from various regulatory authorites to prove it for use. If you think that even a fraction of that could be doen for a mere billion dollars, you are having a laugh. It costs more to develop an aircraft - the F22 cost $43Bn, the A380 cost $15bn, the 787 cost $16-18bn. These are fairly conventional vehicles with well established design rules.

At 15km/s you would need vast heat-shielding from aerothermal effects, other wise you'll end up with a vast, radioactive crater with the liquified remains of the ship and cargo laminated over the top.

You'd make far more money in commercial space launches than a military application

Well maybe your right about that money thing, my freind had not typed in a 0 by accident when he sent me the cost report.

As to vulerability of this ship, it will be heavily armored and protected, so if anyhting does make it through it's AEIGIS type defense system, Phalnax guns (the new oens that track projectiles too,) and possilby laser defeneses. As well as it's Jamming and Electronic warfare systems. it could take a few hits. It will be most vulnerable druign re-entry, but during this time sensors will have a hard time tracking the ship, so it will be much harder for them to hit us.

 

Well maybe your right about that money thing, my freind had not typed in a 0 by accident when he sent me the cost report.

As to vulerability of this ship, it will be heavily armored and protected, so if anyhting does make it through it's AEIGIS type defense system, Phalnax guns (the new oens that track projectiles too,) and possilby laser defeneses. As well as it's Jamming and Electronic warfare systems. it could take a few hits. It will be most vulnerable druign re-entry, but during this time sensors will have a hard time tracking the ship, so it will be much harder for them to hit us.