Ion drive efficiency--how have you used them?

[birrhan]

So we all know that ion drives are ridiculously efficient but weak. I was just wondering what real-Kerbin examples you have of using ion drives to move payloads. Like, what mass did you move, how many ion engines, how did you power them, and around which planet/mun? Let's stick with a discussion of the stock ones, I know the modded ones are more powerful.

[dlmarti]

Anything more than a tiny probe, and you can forget about ion drives.

I typically use them to put satellites in orbit around other planets.

[Frederf]

I'm considering using ion engines for a docking tug as it provides a very good level of control over velocities.

[cesarcurado]

I've used them in probes before, for small corrections over time and if I needed to move it later.

Also I've tried one of these "Ion Gliders" or whatever you call them, they are just amazing, maybe I will try to make my own when I have the time for it.

[Bacterius]

One of my first craft I put in orbit around Kerbin was a 15-20 ton (don't remember exactly) manned probe (the 3-man module) powered by three ion engines mounted on a tricoupler and lots of solar panels. It didn't have any functional purpose other than to look cool (and it did) so it didn't have much in the way of payload, however I really liked fine-tuning orbits. I hadn't yet learned rendezvous and docking so I never used it for that, but I did get the craft in a near-perfect synchronous orbit to an accuracy of 0.25 metres. I think that was mostly luck though, since I never managed to do it again

But, damn, was it slow! Changing orbits was so painful I had to add an extra stage to my rocket to push my probe into a higher orbit rather than leave it in LKO to minimize burn times with the ion engines. Not really practical.

[rryy]

I like to put them on probes for looks. They don't do a much work because it uses a larger rocket to take it to the target orbit and once it is in its target orbit, it doesn't do anything other than precise maneuvers the rocket can't do.

[XaTriX]

For very light plane i've use them.. Otherwise i didn't use them with other vessel. In fact i've test it with an ion-proble and it was... awful

XaT

[bigdad84]

I did an Eve return trip back in 0.18, and stuck an ion engine to a Mk1 capsule for the return trip back to Kerbin.

EDIT: after of course piercing through Eve's THICK atmosphere with my extremely large and complex lander.

[annallia]

I use them on my satellites so I can change their orbits if need be, same goes for probes but ultimately they end up unused as I tend to leave it in the capable hands of the rockets that get them there.

That said I did make an ion powered rover for minmus, was fun to drive but didn't go very fast.

[Brofessional]

I've done an SSTO spaceplane with ions instead of rockets.

[Accelerando]

I used one on a transmunar tug to slow down into Mun orbit. About an hour of game burntime

[leax256]

I really don't use them much since I can simply build a larger rocket and get there faster. perhaps I will change my tatics once money is introduced or the 1.25m ion drives are added

[Astronomer]

I sold them to NASA

[Anton P. Nym]

I'm experimenting with ions at the moment; I built an ion-boosted glider that, last time I ran it, had a greater than 30:1 glide ratio. (I used a small booster to get it up to 2200m, I landed the glider 63km NNE of KSP... only because it got dark then and I didn't want to crash in the dark after running the batteries out, so the ratio's probably even higher. I'm hoping to refine it and use the design to probe Eve.

I also have an experiment running now to take only size 1 or 0 parts and make a cheap Moho orbiter. I call it *pinky finger* MiniMoho, the whole thing (probe, 2-stage booster, and gantries) weighs 9.7 tons and costs a squeak over $25 000 kerbucks... which makes it slightly cheaper and vastly lighter than the first booster stage of my chemical/nuclear-thermal Moho orbiter. I'm thinking of writing it up for a blog post here later.

There are very interesting things that can be done with those engines... if you're willing to abuse the physics-warp key or run long burns in the background while doing housework or something.

-- Steve

[legoheli]

I see few of you build big. Here is my interplanetary ion drive vessel, currently in high Kerbin Orbit (beyond Minmus), waiting for a refuelling of its xenon tanks before heading out to interplanetary space. Pictures taken during the initial burn away from LKO. The only mods involved here are the two Orions docked to the station.

It does NOT accelerate fast at all. It gets around 0.01G according to the acceleration meters on board, but it is VERY efficient. The solar panels are arranged for maximum efficiency as well so that no matter the orientation, electric charge will not be depleted at full thrust.

[Sma]

I use them on my kethane probe, and now I'll be using it on my kethane/isa mapsat probe. Works rather well for that. I use just two of the gigantor solar arrays, and with the new parts I currently have mocked up a probe that uses the large (4000) battery, and for the sake of symetry, at the other end I used the large RCU. IN between (other than the rockomax adaptor) I but the structural fusealage, which is where the solar panels attach, along with 2 jr docking ports (on the rare occasion when it needs to be refuel).

[ecat]

I've done some experimentation, even in large numbers they are somewhat lacking.

Ion Flair Mk I, I forget the total part count but with over 450 Ion engines you can imagine the rest.

The Ion Flair series is so environmentally friendly and earns so many environmental credits that an atomic lift stage is not so much justified as it is mandated.

Both launched to orbit by an Orion nuclear pulse stage http://forum.kerbalspaceprogram.com/showthread.php/28428-Orion-aka-Ol-Boom-boom

[maltesh]

In 0.18, after the prototype Ion Maiden, I built the Ion Will. KSPX parts for smaller ASAS, smaller RCS, and larger Xenon tank. Twin side-by side ion drives, powered by laterally-placed gigantor solar panels.

In early 0.20, the Ion Man. Again, KSPX parts for the same reasons.

This is the Ion Cross, from late 0.20.

One of the interesting things about Ion drives: THeir thrust isn't blocked by the parts of your ship, so you can stack them.

I took her from Kerbin to Eve on an "I want to leave now, screw waiting for windows" course.

Given that the spacecraft only had the two ion engines, landing went poorly.

I generally only use Ion drives for these weird single-man recreational craft; I don't really consider them worth the extra hassle for sending spacecraft or probes to other destinations. After sending one to Dres in the early days of 0.18, I went back to using the LV-N for Serious Business Spacecraft.

[WhiteWeasel]

1.4t

4.3k Dv

Capable of firing at full thrust at jool. Have a whole adventure documented at the spacecraft exchange. http://forum.kerbalspaceprogram.com/showthread.php/35878-MLAS-Presents-The-Deep-Space-Splitter

For closer distances remove the extra gigantor and add something to balance it and you got a handy communications satellite.

Edited July 30, 2013 by WhiteWeasel

[Anton P. Nym]

To compliment the other photography:

There's MiniMoho on the pad, in all its 9.7 ton glory.

And here she is in her 1000x100km Kerbal parking orbit, awaiting the upcoming transfer window.

The Arro Ghost mk 1, my first successful ion-boosed glider. That achieved a 20:1 glide ratio. The mk 1bis (using the new stock quad-coupler part instead of the 3-dual coupler kludge, and using less xenon) got 30:1 before I had to abort the test because the sun set...

-- Steve

[Alfondoo]

Microlite

[Kenobi McCormick]

I use them fairly often on fuel tankers to ensure the liquid fuel in said tanker is 100% unused. Before I got a new computer I absolutely relied on them to run my space program because I couldn't get acceptable framerates with chemical rockets capable of going beyond Minmus.

For what it's worth mine are edited quite a bit. 25kN per engine instead of a paltry 500 Newtons. So performance wise they're no different than the Rockomax 42-7S. They just require an entire forest of solar panels in conjunction with a nuclear reactor to run instead

Edited July 31, 2013 by Kenobi McCormick

[Danger2007]

I use them on my MapSat satalite. With a enough xenon you can go quite far, although you need very long burns! With 2 large (stock) xenon canisters and some left over rocket fuel, I got to Eve. The retro burn to slow down to orbit took an hour and a half plus tons more to get a usable orbit for scanning.

Edit: as you can see from the ribbon I didn't have much left for an inclination change!

Edited July 31, 2013 by Danger2007

[strongest_2hu]

To everybody who is building ion gliders, remember that you're probably getting as much (if not more) infiniglide thrust as ion thrust. If you take all the engine/electrical equipment off you can fly pretty well, forever. I know they're fun and we've all tried it, but it's pretty suspect to call it an effective use of ion engines when the control surfaces alone could send the craft to the upper atmosphere.

[spikeyhat09]

thing is, they may be efficient but you get infinite fuel in sandbox anyway so why not put a rocket engine on just to speed it up