Jump to content

Ion Engines - Why?


RocketBlam

Recommended Posts

  • 2 months later...

Bop/Pol income

I'm playing version 24-2, a 'career' game. Having visited Bop and Pol, further contracts are offered to do science there and plant flags. So I arranged my original 'visit' mission to be multi-use.

I hadn't used ion drive before 24-2, and reading old posts I'm very glad I didn't. With 1/4 the thrust and nearly twice the electricity use, it would have been a chore. I gather the new version of ion drive is less solar-system-physics 'real' (I've never looked it up myself), but for me it makes for better game play. Even with liquid fuel etc, having set a Jool rendezvous, I can boil a kettle and make a cup of tea while the ship goes around an orbit. I gather the old ion engine required physics-warp, a timer, and a book to read, just to make the orbit adjustment.

The thing I would change if I started again would be to send a lesser-known Kerbal on the mission (I sent Jebediah on the mission and I miss seeing his laughing face)

The ship got to Bop largely using an atomic engine in the 3rd-to-last stage, having got the craft up using a bunch of 650-thrust SRBs. I can move the lander back and forward between Bop and Pol using fuel from the fuel ship, and refill the lander tank when necessary. The pictures show the ships on Kerbin escape, as they would look docked in orbit of Pol, and the lander on Pol.

The income generated will, at some stage, pay for some outlandish and stylish vessel, rather than something so cheap/functional/practical.

15mBjFJ.jpg

63pUJBC.jpg

cmHTfo9.jpg

Link to comment
Share on other sites

Ions are fantastic for small probes. The burn times are long enough that you often need to adjust on multiple orbits, but it's not too bad. What I've found best is to NOT use the probes straight from Kerbin, since the burn times will just be uncomfortably long (even with the recent improvement to ion thrust). Here's my main probe design:

http://i.imgur.com/Y0FRlFC.png

Basically, an LV-N transfer stage carries four small probes (seen at the top) to whichever planet needs them. Once it's passing through the SOI in question, it fires one of the probes, which can then deploy its solar panels and maneuver itself into whatever orbit is needed. The LV-Ns keep the burn times extremely manageable, while still having plenty of efficiency. The probes themselves have a Kethane scanner, mapping scanners, plus the full array of standard sensors and an antenna (which allows them to be used as one-shot atmospheric probes for places like Jool).

But don't discount other uses of ions. My SSTO spaceplane can mount ion pods (xenon plus an engine) on its wingtips; they add ~2 tons to its 32-ton mass, but give it enough raw delta-V to get from Kerbin to Laythe. Sure, the burns take a couple hours, but I can just watch a movie while it goes on its way. The only real headache, fuel storage, can be solved if you download certain mods that add larger xenon tanks (or mod a part for yourself) so that you don't need dozens of tiny tanks to bloat your part count.

This is exactly what I use them for. Go to Jool with mapping and scanning probes and can hit all the moons with no problems.

Link to comment
Share on other sites

So far i use them strictly for my Kethane searching satellites. The small lightweight craft is perfect for such a small and efficient engine. Adjusting the orbit is a piece of cake.

This is what I use them for too... So I did find a use for them. Since the Methane detectors need a lot of solar too, they work well for the probes.

Link to comment
Share on other sites

One of the best and simplest use of ion engines is a lightweight satellite in the Jool system of moons.

Raising and lowering your apogee you can do a fly by of every moon in one mission. Providing you keep the weight low burn times aren't any longer than what you'd get with a nuclear engine with a capsule attached.

Link to comment
Share on other sites

Ion landing on Dres

I was surprised to find I could land a ship using ion drive on Dres (and thus presumably could do the same on Ike). Having separated from the fuel ship, I started with this ship in an orbit of 25000m, slowed/descended, landed, took off again, and was able to rendezvous back with the fuel ship. My landing site was at '145m'. All up it took 400 units of ion fuel (from a tank with 700 units) to land and get back up.

YuBkVDF.jpg

Link to comment
Share on other sites

Guest
This topic is now closed to further replies.
×
×
  • Create New...