Larger xenon tanks

[THX1138]

I'd like to be able to store a larger amount of xenon on a space craft or space station so I can refill probes. I'd also like a tank that's still small but bigger than the 700 unit-size.

[SaturnV]

Ion engine suits large vessel not very well, so do large xenon tanks.

Obviously dev forget the need for xenon gas refueling station. You have to use lot of tanks in stock, or get larger ones from mod

[Chezburgar7300]

I don't think this'd be on their list of to-do's as Ion Probes are more than usually very small.

You could try out the Near Future mods, IIRC it has a pretty sizeable xenon tank.

[Pthigrivi]

Man we really really need this. Ion engines are usually used for probes because the tanks are so small, not the other way around. Right now I use batteries of ion tanks on docking ports to fuel 4 and 8 ion engine clusters for interplanetary shuttles and orbital science platforms mainly so I can dump them because refilling them is so tedious.

[AbacusWizard]

A couple of versions ago I made a reasonably large interplanetary ship powered by an ion drive (with tanks of conventional fuel to refuel the landers). It actually worked quite well while it lasted; the only reason I abandoned the idea and switched to atomic rockets was... the tiny xenon tanks. Having to select all of them one by one was a huge pain, and the high part count led to slow performance (especially when I tried to dock with my space station). A larger tank, or even one part representing a cluster of many small tanks, would make this much more feasible on both accounts.

- - - Updated - - -

One workaround I found for the refueling issue: modular construction.

When designing the ion-powered ship, put all the xenon tanks in a cluster on a docking clamp. When it starts to run out of xenon, send up a transport craft carrying a full replacement cluster of identical design. Instead of manually refueling each tank, just detach the empty module and attach the full one.

Unfortunately this doesn't fix the issue of slow performance due to too many parts.

[Pthigrivi]

^That exactly. High five Abacus.

[AbacusWizard]

Credit where it's due: I got the idea for modular refueling from Arthur C. Clarke's _The_Exploration_of_Space_ (which was written in the 1950s and almost reads like a KSP user manual); he suggests that simply swapping out empty tanks for full ones might be an easier and more practical method of orbital refueling than trying to link up hoses.

[Sean Mirrsen]

I don't think this'd be on their list of to-do's as Ion Probes are more than usually very small.

You could try out the Near Future mods, IIRC it has a pretty sizeable xenon tank.

Pretty much this. The Near Future Technologies mods have both the huge Xenon tanks, and the larger ion/plasma engines to power the long expeditions, as well as larger solar panels and other electrical systems to help with that.

[Jouni]

The lack of larger xenon tanks is the only thing that keeps ion engines more or less balanced. If part count were not an issue, there would be little reason to use nuclear engines, except in landers.

[Secuas]

Or you could get procedural parts for the procedural Xenon tank. ¯\_(ツ)_/¯

[Joonatan1998]

The lack of larger xenon tanks is the only thing that keeps ion engines more or less balanced. If part count were not an issue, there would be little reason to use nuclear engines, except in landers.

Using lag as a balancing method...

At least in career ion engines are balanced by their high cost. (and the high cost of xenon)

Edited January 28, 2015 by Joonatan1998

[Sean Mirrsen]

The lack of larger xenon tanks is the only thing that keeps ion engines more or less balanced. If part count were not an issue, there would be little reason to use nuclear engines, except in landers.

That's kind of exactly why they're so sought-after IRL. They're supposed to be the best way to travel in space.

The biggest problem I see in KSP, is that the so-called "technological progression" in Career is anything but. It just unlocks more of the sandbox part set. All parts are balanced against each other, so you see these kinds of lines of reasoning (like yours) fairly often, when they shouldn't be there at all. In-game and IRL, there can always be parts that are best at a specific kind of thing.

Ion Engines are great, but for that annoying quirk that they require power. Stuck in the shadow of a planet? Can't move. If you use Near Future you can bring a reactor along, but even if you're in Sandbox and don't care about the millions of funds it costs, you're adding significant mass to a ship with already low TWR (because ions are never good for that).

I found myself often using the nuclear engines in conjunction with the MPD plasma thrusters, or the VASIMR thrusters, in Near Future. The reason being that they both use the same resource (Liquid Hydrogen - it's an option in the mod), and LV-Ns don't need power, so if I need a sudden boost of TWR or if I need to move now to make a burn when I don't have available power, they're quite useful.

[Jouni]

That's kind of exactly why they're so sought-after IRL. They're supposed to be the best way to travel in space.

Best for interplanetary missions, where the long burn times don't matter. Not so good at shorter ranges, especially with manned missions, where the extra month required to reach the Moon could matter. KSP ion engines don't have this limitation, because their TWR is so high that burns rarely take longer than an hour.

[Sean Mirrsen]

That's why Near Future nerfs the PB-ION back to its old stats.

[Jouni]

That's why Near Future nerfs the PB-ION back to its old stats.

That only changes the situation for landers, while transfer burns are basically unaffected. Nerfing the ion engines to 0.5 N instead of 0.5 kN would be another matter.

[Pthigrivi]

How much have you used Ion engines? They already place really hard constraints on weight, even if you use 6 or 8 of them. Panel configuration is a big challenge as well, so that you can burn in any direction and still have them all pointed at Kerbol. And they dont work in planetary shadows or for landing on anything but tiny moons. That seems like plenty of balance to me.

The engines are stock. Just one part to save us on part count would open up a huge world of design possibility and make things more fun.

[Jouni]

How much have you used Ion engines? They already place really hard constraints on weight, even if you use 6 or 8 of them. Panel configuration is a big challenge as well, so that you can burn in any direction and still have them all pointed at Kerbol. And they dont work in planetary shadows or for landing on anything but tiny moons. That seems like plenty of balance to me.

I used them for a while after the buff in 0.23.5. My ships are generally large enough that the high part count limits the usefulness of ion engines. My most successful designs include a 7-engine Mun lander and a 12-engine Moho transfer stage. Both used only a minimal amount of solar panels, replacing them with a huge pile of batteries.

[Pthigrivi]

Nice man! Yeah thats an interesting way to go with batteries.. maybe I should play around with that. Definitely helps with the night-side burn problem.

A nice set up Ive found for 1 and 4 ion engine craft is to use mirror symmetry to splay out 4 panel arrays like a dragonfly's wings. That way they the sun is unobstructed when burning toward or away from it, and when burning perpendicular you can just rotate the craft around the z axis to face everything toward kerbol. It really keeps the weight down and you only need a tiny Z-200 battery.

Edited January 28, 2015 by Pthigrivi

[CaptRobau]

That's kind of exactly why they're so sought-after IRL. They're supposed to be the best way to travel in space.

The biggest problem I see in KSP, is that the so-called "technological progression" in Career is anything but. It just unlocks more of the sandbox part set. All parts are balanced against each other, so you see these kinds of lines of reasoning (like yours) fairly often, when they shouldn't be there at all. In-game and IRL, there can always be parts that are best at a specific kind of thing.

Ion Engines are great, but for that annoying quirk that they require power. Stuck in the shadow of a planet? Can't move. If you use Near Future you can bring a reactor along, but even if you're in Sandbox and don't care about the millions of funds it costs, you're adding significant mass to a ship with already low TWR (because ions are never good for that).

The tech progression is indeed a big problem. I hope during the balancing for 1.0 they manage to fix that. It's impossible to balance sandbox and career at the same time and have both be equally awesome. Career really needs the feeling of progression and thus undoubtedly better tech over time. Generally speaking most OP-ish engines have some drawback or another that makes sure they wouldn't outclass all other engines in every single situation even at the end of the tech tree. Sandbox should be balanced by players themselves, by restraining themselves from constantly using an engine they consider OP.

On the topic of larger xenon tanks: only if we get more advanced electric propulsion. Bigger engines like VASIMR thrusters or MPD thrusters can all run on Xenon (no reason to add another resource just for those engines) and they'd really need the bigger engines compared to the small ion engine in the game now.