# QuestionDual Stage 4 Grid Ion Drive possibilities

#### recklessasiandriver

I would like to invite you to peer review my idea.

Has anyone heard of the Dual Stage 4 Grid Ion Drive? Please check out the numbers:

https://en.wikipedia.org/wiki/Dual-Stage_4-Grid
https://www.esa.int/gsp/ACT/doc/PRO/ACT-RPR-PRO-IAC2006-DS4G-C4.4.7.pdf

Based on these numbers:

https://1drv.ms/x/s!Aotveh8OjBiliuBwbLHfAm42-In3eQ?e=dvGeRF

I created a design of an interplanetary spacecraft that will maximize surface area for the drive to maximize the thrust as the thrust is a function of surface area. I also noticed that solar panels are optimized for this too so on the sides of the craft that is cubic shape I also placed solar panels which would be useful when the ship is either moving slowly or in an orbit around a planet and not in transit.

The ship has to be nuclear powered and I decided for this thought experiment to make it a Fast Neutron Reactor and got the figures of wikipedia. If there are any issues with this decision please let me know. I just assumed that it would be lighter than 10 tons which I imagined to be the mass of the ship's empty weight. The nuclear fuel U238 will have to be very highly enriched and able to breed. I feel I made a mistake in my numbers because I didn't factor in the return trip so I really should have doubled the numbers of nuclear fuel and propellant, so there really should be another 10 tons on top of the 20 tons fully fueled. 10 ton empty + 20 ton of nuclear fuel and propellant should give us a very comfortable ride to Mars or Titan at 30 tons. Perhaps throw in a lander too because this ship is not designed to land on any moons or planets. Oh and maybe factor in food, water and crew another 5 tons for 35 tons. But if you fly in a convoy of at least 2 or more cubes then things like landers can just be on one or two ships and the others can store food and water. Then you're back down to an average mass of 30 tons but now you also can link up and have artificial gravity. See below for more details.

Although you still could have done it with the initial configuration but reduce the to and return trip and still be more comfortable than ISS astronauts sometimes spend at least a year there.

You could also have a cube sent ahead with a lander but it took it's sweet time controlled by AI with no crew but plenty of return fuel and propellant. Then you could fly the initial configuration ship there at warp speed and have a return cube waiting for you to take you home after your stay.

The ship is a scaffold but it can be optionally panelled and pressurized inside to maximize breathable volume allowing 4,900 cubic meters of habitable volume. The ship will need the ability to radiate away nuclear reactor heat by running coolant through the scaffolding and transfer the heat into any panels added so that it can radiate into space.

From the numbers I generated for specific impulse and my assumptions for needed fuel and mass for a ship, I came to the following conclusions about what is possible for a team to visit Mars and Titan:

Cut travel time to Mars from 7 months to 3 weeks.

Cut travel time to Titan from 7 years to 7 months.

First and last 12 hours of interplanetary travel leg will give artificial gravity to the ship especially if it has multiple deck levels. Although you will only feel 1/10th Earth's gravity at 1m/s/s it's still better than nothing. You can also rotate the single cube for some artificial gravity but there would be some Coriolis effect because the diameter is only 17m.

Flying a 2nd, 3rd or 4th cubic ship in formation will give you the option to connect them all together for more artificial gravity by rotating a rectangular interconnected mass. At a planetary destination such as Mars or Titan they can link up in greater numbers or with longer scaffold for slower rotation in exchange for longer structure for less Coriolis effect. This would be great for Geosync orbits above Earth/Mars too so that station crew will have a 24 hour day/night.

#### Phillip Huggan

I plan cathode-less (GIT) as it is a simpler solid-state design, and I'm mildly stronger focusing on the antenna design. The solar is great as long as we choose Earth as a star. A centrifuge is risky. I plan Faceoff's jail hopefully textile wearing. Xenon is expensive until we find Xenon but higher mass is better. Pollution is easy here. Si until the Oort at least and Fe beyond is cheap enough. There is a need for maneuvering thrusters, I'm not too strong here...A yaw at high speed will rip the ship apart so many sided or round is a better exterior. There many solutions to keeping the exposed thrust/ship interface away from space hazards. Mine is classified but the iD4 unfolded shielding of its beam might do for the Solar System.

#### billslugg

Well thought out presentation, reckless. A solution to the Coriollis force problem inherant with spinning a capsule is to put two capsules tethered about 700 m apart. One g, about a minute per rev. Moderate strength requirements on the tether.

#### Phillip Huggan

I've just read propulsions. I figure ion engines are too dangerous to consult (\$) about, but the projected use of them to give asteroids a shot seems fairly likely w/ Space X's Mars tech going to someone American.
Hall Effect and VASIMR look good for consulting. I shouldn't use metamaterials or improved RF antenna sources consulting. And many of the thrusters are already done. I'm missing out on improving electrosprays but I can advance similiar deposition technologies safely. It looks like existing power supplies will be a big point of improvement, especially getting smaller.
My reports will guess: 2030s Moon-Mars-2 asteroids. 2040s Saturn. 2050s other outer gas planets. RF GID is mine. I'll be hiring for probes in NY. I'm planning biolistics satellites at Triton and past the heliopause made in Bellingham WA. To model propellant, it is occasionally entangled and magnetically interacting with other charged drops, and these are both expensive properties to model (a particle of propellant gets a sword symbol to let you know it isn't being modelled as entangled but you still have to know where it is and where parallel mildly interacting particles are almost as if you are still using entangled math). More cheap clone modelling is needed while still approximating the ion 3D layers...A Saturn tour would see fuel extracted from Enceladus and used to scout the system, maybe 10m a side. 17m is good dimensions for Triton. 30m to kill a comet at 1 LY and land it slowly on Nereid if desired.

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