Ant Engines

[LordFerret]

Ant engines you say? Why, what else would you use them for?.....

[numerobis]

They come early in the tech tree, so I used them for my first few lunar probes.

I occasionally want a small engine on my large spacecraft to do very small corrections. There, the requirements are low mass, low thrust. Isp is not very relevant, so the LV-1 is great -- particularly given it burns fuel that I'm bringing anyway (not monoprop, which I don't otherwise use).

[waterlubber]

I use them on satellites. If I'm using oscars I will use them. However, I often used cheap interplanatary probes for contracts (Explore Duna, etc.) that consisted if a 48-7S and a FL400, which easily gets 4k DV

[magnemoe]

One interesing thing about them is that they tend to come up in science contracts very often.

This makes them interesting to use around other bodies,

[moogoob]

I use them on satellites. If I'm using oscars I will use them. However, I often used cheap interplanatary probes for contracts (Explore Duna, etc.) that consisted if a 48-7S and a FL400, which easily gets 4k DV

My standard umanned lander is based on that setup, only with an flt-100 and minimal other equipment - the un-parachuted variant gets 4400, enough for a Tylo landing, I think. Haven't tried that yet - not sure what the TWR is like but it should be fine as it's about 2 on Eve.

Edited November 29, 2014 by moogoob

[HafCoJoe]

Yeah I am a fan of the ant engine and I do use them from time to time, but yeah I agree their engine sound is quite annoying. It'd be cool if SQUAD made their "less piercing". Only in Beta!

[waterlubber]

My standard umanned lander is based on that setup, only with an flt-100 and minimal other equipment - the un-parachuted variant gets 4400, enough for a Tylo landing, I think. Haven't tried that yet - not sure what the TWR is like but it should be fine as it's about 2 on Eve.

Holy cow, 2 on eve? That's 12 on Tylo AFAIK, kerbin is very similar to Tylo when it comes to gravity.

[Starman4308]

Holy cow, 2 on eve? That's 12 on Tylo AFAIK, kerbin is very similar to Tylo when it comes to gravity.

You're badly overestimating Eve's gravity. Eve has a surface gravity of 16.7 m/s^2, kerbin is about 9.81 m/s^2, and Tylo is 7.85 m/s^2. As such, an Eve TWR of 2 is about 4 on Tylo.

[waterlubber]

You're badly overestimating Eve's gravity. Eve has a surface gravity of 16.7 m/s^2, kerbin is about 9.81 m/s^2, and Tylo is 7.85 m/s^2. As such, an Eve TWR of 2 is about 4 on Tylo.

Ahh, sorry, the atmo is 6x gravity, right?

I would use ants more if they weren't rectangular.

[boxman]

Let's just take some time to think about the ant engine. Specifically, why everyone hates them so much. They're actually very handy for small landers. They're often used as an example of a useless engine, but please give them some love for their high twr and cheerful attitude.

I have never really heard of anyone hating those. Seen quite a few people use it for small probes.

But one thing that I do hate is the horrible engine sound.

[sal_vager]

Ffffppppffffpppfpfffppppfpfffppfffffpppffffpppt

Well, that's what it sounds like to me anyway.

[NQMT]

That's probably the most accurate description of anything I've ever read.

[Starman4308]

Ahh, sorry, the atmo is 6x gravity, right?

I'm not sure what you're trying to ask. Gravity is a force, atmosphere is stuff you have to fly through. Atmospheric drag can be 6x gravity, but it is dependent on how fast you are flying. If that's what you're asking, Eve's atmosphere at sea level is 5x thicker than Kerbin's, which makes things difficult and almost painfully slow.

Back to the purpose of the thread, I've used Ants at times. I usually have bigger payloads, but if I just want to get a Stayputnik somewhere, I usually use an Ant engine (helps that RealFuels rebalances it so the O-10 is not completely superior for low-mass probes of delta-V around 3 km/s).

Edited November 30, 2014 by Starman4308

[boxman]

Ffffppppffffpppfpfffppppfpfffppfffffpppffffpppt

Well, that's what it sounds like to me anyway.

Indeed that pretty much describes it

But what is even worse is that it seems to be much louder as well than any of the other engines and sounds.

[Rithsom]

The sound loop is noticeable too. It's about 2 seconds long.

[numerobis]

Ffffppppffffpppfpfffppppfpfffppfffffpppffffpppt

Well, that's what it sounds like to me anyway.

I keep forgetting this game has sounds and music -- except when I upgrade and haven't gotten around to muting them yet.

[Coga19000]

Well, by some quick research on the wiki, the Rockomax 24-77 is radially-attachable, costs 180 Funds less than a LV-1R (but 180 Funds more than the normal LV-1) per piece, weighs a bare 60 kilograms more, has 16 more kilonewtons of thrust, 30 more seconds of specific impulse under 1 atmosphere of pressure, 10 seconds more in the vacuum of space, and literally identical on every other aspect -and when they are unlocked at the exact same node, it's not really too much of a choice. Even the animation and sound is better -the Rockomax 24-77 looks and sounds almos like a dignified engine (more like a Sepratron, if you ask me), while the Ant looks like it's barely spraying propellant around, which does not look too sae and realistic either.

[merendel]

while the Ant looks like it's barely spraying propellant around, which does not look too sae and realistic either.

And now I'm pictureing the Ant as being the end of a fire extinguisher nozzle. There is a little kerbalized hamster inside jumping up and down on the actuation lever resulting in little white puffs of thrust to plume out the back.

[The Yellow Dart]

So I didn't read this whole thread so this may have been said, but ant engine performance is simultaneously accurate and inaccurate. The 290 Isp is accurate for similar thrusters on most real life satellites and probes, like Rosetta for example, but the reason the Isp is so bad I believe is because of the propellant, hydrazine. The reason hydrazine is used is because it is very reliable for many reignitions, where as other propellants that givea higher Isp require separate ignition systems that only function for a certain number of burns. So the ant engine is inaccurate because it has a low Isp despite using the same fuel as all other rockets in KSP, and also because the benefits of easy ignition are stripped away in KSP where any engine can reignite infinite times. This is a company that sells small thrusters for satellites and you can look at the Isp of the various sizes of thruster: http://cs.astrium.eads.net/sp/spacecraft-propulsion/bipropellant-thrusters/10n-thruster.html

According to that page, their 10 newton thruster was used in Rosetta, Venus Express, Mars Express, and BepiColumbo which is on it's way to Mercury.

[aleis]

I like them for small probes as well, that I frequently add to my manned missions. Just feel if your going to go to the trouble to get a manned lander all the way to another planet the last you could do is leave behind a probe or two.

And as they aren't the primary mission I make them as light as possible, with just enough dV to get them in the desired orbit without having to maneuver the host vehicle

Edited December 2, 2014 by aleis

[Xavven]

So I didn't read this whole thread so this may have been said, but ant engine performance is simultaneously accurate and inaccurate. The 290 Isp is accurate for similar thrusters on most real life satellites and probes, like Rosetta for example, but the reason the Isp is so bad I believe is because of the propellant, hydrazine. The reason hydrazine is used is because it is very reliable for many reignitions, where as other propellants that givea higher Isp require separate ignition systems that only function for a certain number of burns. So the ant engine is inaccurate because it has a low Isp despite using the same fuel as all other rockets in KSP, and also because the benefits of easy ignition are stripped away in KSP where any engine can reignite infinite times. This is a company that sells small thrusters for satellites and you can look at the Isp of the various sizes of thruster: http://cs.astrium.eads.net/sp/spacecraft-propulsion/bipropellant-thrusters/10n-thruster.html

According to that page, their 10 newton thruster was used in Rosetta, Venus Express, Mars Express, and BepiColumbo which is on it's way to Mercury.

Hm, this is a good theory. We could still make it believable if we imagine it's using Aerozine 50 (a mix of hydrazine and UDMH) + N₂O₄ (Dinitrogen tetroxide), which is a hypergolic bipropellant, very reliable for reignition. The ascent engine on the LEM used it and had an Isp of 311.

Edit: Just read your link and saw the engine using MMH + N₂O₄ or MON (mixed oxides of nitrogen), so disregard my comment above. I think KSP oversimplifies the fuels into "generic bipropellant" and "generic monopropellant," so if you want to get around that without mods, you can simply have self-imposed rules to A) have a separate fuel tank for different engine types, and not transfer fuel between two tanks that would use different fuels/oxidizers.

ReEdit: and I just noticed my error about the Aerozine 50 engine reigniting... the LEM ascent engine would reliably ignite once, but the combustion destroys the engine. /facepalm I should go to bed.

Edited December 3, 2014 by Xavven

[The Yellow Dart]

so if you want to get around that without mods, you can simply have self-imposed rules to A) have a separate fuel tank for different engine types, and not transfer fuel between two tanks that would use different fuels/oxidizers.

Yeah, that's what I was thinking when I was writing it. The only way to make it make sense is to install both Real Fuels (I assume that is the sort of thing it does, I've never used it) and Engine Ignitor mods.

[InterCity]

why everyone hates them so much?

Because Kerbodyne.

[Starwhip]

Ffffppppffffpppfpfffppppfpfffppfffffpppffffpppt

Well, that's what it sounds like to me anyway.

Yup.

Also the KSSSSHwhoosh noise of staging. (Which is sometimes accompanied by numerous explosions.)

[John FX]

I like them. If you have multiple small probes on a larger ship, you can carry much more Dv in the form of oscar and ant than you can with others forms of propulsion.

I would imagine you could get 8 ant probes or 5 LV probes for the same mass. I may be wrong, that`s off the top of my head.

They are also good for tiny space scooters. This had a couple of radial mounted ones on an oscar