what is the best engine in KSP?

[KerikBalm]

there is no best engine...

but i I could only use one engine... it would be the rapier for its abiity to get stuff to LKO

Engines I particularly like for many designs:

KR-2L: decent thrust even at sea level, great Isp in a vacuum (where I use it the most for launching large craft on escape trajectories)

Mammoth: for getting payload to LKO when I don't want the added complexity of airbreathers

Nukes: generaly purpose vacuum engines

Poodles: when I want more vacuum TWR, but the KR-2L is overkill

Terriers: for small vacuum landers

Ion: when I'm desperate to pack on more dV (as when trying to do a fully reusable mission to moho)

 

The other engines I don't use so much. I use aerospikes and vectors for eve landers. Sometimes the aerospike for a small ejection stage for probes. I also use it on my Tylo SSTO lander, although the poodle is a very close competitor (depends on how many kerbals and how much science you want to bring)

thuds, the sub 1.25m engines, the skipper/mainsail, the lv-t45 and 30.. I still use them, but not nearly as much as the above engines...

[Corona688]

Best engine all around:  The swivel.  It unlocks early, generates power, vectors, has enough thrust for lift-off, and is efficient enough for orbital stuff.  The only other engine even close is its unvectored twin.

Best engine by weight:  The "spark" engine.  Only a few bigger, stranger engines can beat its thrust-weight ratio.  It's not bad efficiency-wise either.  And this is after it was nerfed.

Best engine by efficiency:  The terrier(and the poodle, its rockomax-sized clone).  For long burns out of atmosphere it's hard to do better.  (I'm not considering weird things like NERVA or ion.)

Best engine by compactness:  RCS thruster.  Nothing else lets you build self-guided probes quite as tiny.

NERVA and ion are only good for interplanetary burns, their super high efficiency is hard to make useful otherwise.

All just my opinion of course.

[MDZhB]

I hardly ever use it, but I really like the ION engine. If you went by what I use the most, my favorites would apparently be the terrier, the mainsail, and the really tall SRB. The first is my go-to landing engine, and the latter two are great for launches.

Of course, the sepatron makes a great missile too...

Edited June 30, 2016 by MDZhB

[cantab]

Overlookable engine fact: If you consider the Twin Boar as a 6.5 ton engine bolted to a 36 ton orange tank, then it's essentially the highest TWR engine in the game, provided you don't need it to push less than an orange tank worth of tankage. And if you deduct the monetary value of the orange tank then the engine effectively costs 11250 funds which works out at 5.6 funds per kilonewton, and that makes it one of the cheapest liquid engines on a per-thrust basis (the Reliant and Poodle are a bit cheaper).

It's too limited to be the "best" engine - good luck using one in an upper stage for starters - but it's definitely one worth considering.

[waterlubber]

The 3.5m super-efficient engine. Can't remember it's new name, though.

I'm also a big fan of the LV-909 and the Ven's revamp Bollard engine.

[The Optimist]

Fun fact: 1 Vector, 1 Kerbodyne-64 and 1 Kerbodyne-16 (and 3 reaction wheels plus the essential avionics) gives you a whopping 4750 dV, with an excellent TWR. It's great for pretty much anything, if you add drop tanks and other modules as needed. The Rhino is nice too, but it's a bit too big and heavy for my purposes.

Edited June 30, 2016 by The Optimist

[luizopiloto]

Don't ask what's the best part... or Squad will nerf it...

[cubinator]

Unity. Also the Terrier and Poodle. The Terrier is a great engine for propelling small ships a considerable distance, and the Poodle is pretty much a scaled-up Terrier which makes it perfect for short to medium range interplanetary missions that don't have an absolutely colossal payload.

[magnemoe]

8 hours ago, cantab said:

Overlookable engine fact: If you consider the Twin Boar as a 6.5 ton engine bolted to a 36 ton orange tank, then it's essentially the highest TWR engine in the game, provided you don't need it to push less than an orange tank worth of tankage. And if you deduct the monetary value of the orange tank then the engine effectively costs 11250 funds which works out at 5.6 funds per kilonewton, and that makes it one of the cheapest liquid engines on a per-thrust basis (the Reliant and Poodle are a bit cheaper).

It's too limited to be the "best" engine - good luck using one in an upper stage for starters - but it's definitely one worth considering.

Yes the twin boar is probably my preferred launcher engine, tend to be either 1.25 meter and T-30, then 1x2 with an gap for skipper in between, then its the mammoth for the heavy stuff. 
Has two ssto rockets who uses the aerospike who I have grown more found of. 

[panzer1b]

No such thing as best engine, but there are 2 that i personally use 24/7. 

Almost all my ships are launched upon those super massive quads because i cant really be bothered to actually engineer a proper lifter despite the fact that i can have a lighter and cheaper solution using other engines.  Its just that i never cared about lifters in the game, and i view them as nothing more then a means to an end, so yeah, ill use the simplest lowest part count solution around, and those 3.5m engines are really the best thing around for that purpose.

Also, nukes have no alternatives right now, so if you are actually planning anything interplanetary without staging and dont want to carry 2/3 of your ship as fuel, you kindof have to use nukes to get anywhere.  800 ISP is so high compared to the 300-350 of LFO engines that you just cannot really use LFO engines for interplanetary travel or even moving around alot in general.  Basically if you want over 2000 dV on a ship, and you are above 10t, and below 300t, a nuke or cluster of nukes will give you workable TWR with the absolute maximum range possible for your ship's mass ratio.  While id love something that was perhaps a stepping stone between nuke and LFO, or even more sized of nukes (so i can have a 5t ship powered by a mini-nuke or so), for now we are pretty much stuck with 1 and only 1 general purpose interplanetary engine.  Virtually all of my capital ships, supply vessels, and anything that isnt excessively lightweight (or isnt an interdictor and thus needs excessive TWR) uses them, heck, even some heavy fighters use them coupled with the rapier to achieve 7000dV after reaching orbit.

Aside from that i pretty much use engines when they seem appropriate, aerospikes for high TWR or for atmospheric operations such as on Eve, 48-7s for small vessels, light missiles, ect, radial engines when i need more thrust but dont have anywhere to place a normal model, SRBs as weapons (sepatrons or RT-5/10) or to launch very lightweight probes(the largest SRB), jets engines for laythe or kerbin, ect.  Id say that in the current game there are no useless engines, and while there a few i use very rarely, ive launched at least a few craft that take advantage of every engine in the game.

[kiwi1960]

Each engine has a purpose for the job at hand, therefore, it could be anything.

However... first stage rockets (engines and fuel tanks, plus boosters if needed) would have to be the SPACE Y mod... gotta LOVE those monster tanks with monster engines....

overkill plus.... love it....

 

[KerikBalm]

@panzer1b

Capital ships, interdictors? *sigh* KSP engines aren't balanced around simulating space operas.

2000dV on one ship needs nukes?

pffff Ive made multiple types of single stage to tylo surface and back to orbit landers: all chemical engines: poodles, aerospikes, rhinos, mammoths, etc.

That requires >4,000 m/s dV and better than 1:1 TWR.

going IP without nukes or ions is perfectly feasable, even with reusable ships.

dV to anywhere is roughly 1/3 the values needed for the real life analogue.

350 Isp in KSP is like 1050 Isp in RL... Better than the real Nerva engine could have got. Solid core nukes cant really do that...

[Guest]

If I had to pick one engine as my go-to for everything it would probably be the Rhino. Clustered Vectors are probably more OP though.

My favourite stock engine is the LV-N, because NTRs are cool, but I am increasingly using the Skipper of all things as a vacuum drive.

[Vaporized Steel]

Rapier is my fave for sure.
That said, I dislike I need 400 parts for my really, really huge SSTOs to get heavy weight into orbit, because the stock game lacks larger rapier engines and air intake parts.

[HazelPine]

I really love the Skipper, since I do lots with 2.5m rockets, and it has just enough thrust to heft big things up, and enough efficiency to be used as a transfer stage to most places. Also, it looks really nice!

[Corona688]

To be honest, "large" and "ssto" aren't really things meant to go together.  You can do it, but if it was easy that'd be game-breaking.

Edited June 30, 2016 by Corona688

[Cairol]

For 1.25m rockets, the LV-T45 is my most used engine besides the Terrier.
For 2.5m rockets, it's the Skipper and the Poodle.
For 3.5m ascent stages, it's the Mammoth.
For planes, it's the RAPIER.

So I consider those as the most useful, because I use them the most. (makes sense, ha? )

[wumpus]

No SRB love?  Go check the "cheap and cheerful challenge", those beasts are nearly all kickers by mass, and cheaply get mass into orbit.  So three cheers for the kickstart, the cheapest way to get delta-v and TWR on the launchpad.

Once in space, terriers never go out of style.

[klesh]

Really dig the spark engine for my 0.625m needs. 

[panzer1b]

3 hours ago, KerikBalm said:

@panzer1b

Capital ships, interdictors? *sigh* KSP engines aren't balanced around simulating space operas.

2000dV on one ship needs nukes?

1st of all i have my own way to play KSP, just because someone (you are by no means the first to say something of this sort) disagrees doesnt mean im going to change what i enjoy in KSP, nor how i play it...

2nd of all, the reason i need nukes to obtain 2000dV is because almost all my combat ships have at best 1/2 total mass being fuel, many of them as low as 1/4 fuel (structural panels/girders/ibeams, and ofc a handful of 4-5t missiles are pretty heavy when you add it all up...).  I have made plenty of LFO only vessels, some of which had in excess of 6000dV, but most used staging and were extremely heavy (and had very little payload fractions, which doesnt work if you need armor).  Yes other engines work, but why should 2/3 or even more of my ships be fuel when i strap 2-3 nukes on and can achieve the exact same thing with a fraction of the fuel/mass.

[problemecium]

The Unity engine. Specifically Unity 5. Without it KSP would be literally unplayable ;P

[KerikBalm]

1 hour ago, Vaporized Steel said:

Rapier is my fave for sure.
That said, I dislike I need 400 parts for my really, really huge SSTOs to get heavy weight into orbit, because the stock game lacks larger rapier engines and air intake parts.

any pics of this SSTO? what mass does it put into orbit? I got my heavy lift SSTO down to 200 parts exactly. It lifts about 150 tons to orbit, and can carry quite a big payload:

And Idea of its payload size (earlier versions):

* 3 kerbal eve lander^

This: http://i.imgur.com/JiHWstz.png + this: http://i.imgur.com/FOfPjuO.png =

ie, this payload:

http://i.imgur.com/rq1irRl.png

Which as you can see masses 226.6 tons

There was plenty of fuel left in the SSTO, as neither payload was close to the maximum payload weight.... it was mainly a problem of dimensions.

[Vaporized Steel]

@KerikBalm

Im on my phone now. Mine lifts about the same payload. But i never can get my large cargo ssto's either aerodynamic enough, or with sufficient thrust. Which results in needing 50rapiers in order to get up to speed. 

Although your design looks very nice and inspiring, may give me some ideas what and how to improve my own.

Edited June 30, 2016 by Vaporized Steel

[KerikBalm]

11 minutes ago, panzer1b said:

1st of all i have my own way to play KSP, just because someone (you are by no means the first to say something of this sort) disagrees doesnt mean im going to change what i enjoy in KSP, nor how i play it...

2nd of all, the reason i need nukes to obtain 2000dV is because almost all my combat ships have at best 1/2 total mass being fuel, many of them as low as 1/4 fuel (structural panels/girders/ibeams, and ofc a handful of 4-5t missiles are pretty heavy when you add it all up...).  I have made plenty of LFO only vessels, some of which had in excess of 6000dV, but most used staging and were extremely heavy (and had very little payload fractions, which doesnt work if you need armor).  Yes other engines work, but why should 2/3 or even more of my ships be fuel when i strap 2-3 nukes on and can achieve the exact same thing with a fraction of the fuel/mass.

1st: yes, you have your own way to play KSP, and that's fine... However you said: "Also, nukes have no alternatives right now"

Nukes have plenty of alternatives. You've simply chosen a style of ship that plays to their strengths, as your style does not at all emphasize reducing dry mass.

2nd: you said "without staging and dont want to carry 2/3 of your ship as fuel, you kind of have to use nukes to get anywhere.  800 ISP is so high compared to the 300-350 of LFO engines that you just cannot really use LFO engines for interplanetary travel or even moving around alot in general.  Basically if you want over 2000 dV on a ship..."

2/3 of your ship as fuel means a wet:dry ratio of 3...

Lets look at the actual mass rations needed:

Ions: 1.05 ... ie 5% of your ship mass must be propellant

LV-Ns: 1.291 ... ie 29.1% of your ship's dry mass must be propellant 1-1/1.29  = 22.5% of your ship mass must be propellant

Poodle: 1.7925 ... ie 44.2% of your ship mass must be fuel

KR-2L/Aerospike: 1.824 ... ie 45.17% of your ship mass must be fuel

Swivel/320 Isp engine: 1.8916 ... ie 47.13% of your ship mass must be fuel

Vector/315 Isp engine: 1.913 ... ie 47.77% of your ship mass must be fuel

Rapier closed cycle/305 Isp engine: 1.953 ... ie 48.79% of your ship mass must be fuel

LV-T30/300 Isp engine: 1.9732 ... ie 49.32% of your ship mass must be fuel

All of these are well below the 66.67% threshhold you've set (2/3rds of your ship as fuel) ... So by your own criteria, all the LFO engines are satisfactory.

With use of ISRU, you never really need more than 2000 dV at once to get to a destination, with the exception being landing on laythe or moho.

[Kerbinchaser]

I love the Rhino. Why? My Kerbals like big engines.