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[Girlinhat]

SRBs are useful for very heavy rockets.  For simple lander missions, not needed.  What you really want, is some mod that enables Dv and TWR recording (Mechjeb or Engineer).  Your ascent stage should aim for a TWR of 2 or so, just as a good baseline (there's more complicated rules with the terminal velocity, but just rule of thumb, go for 2 TWR).  When you're out of atmosphere, you generally want ~2,000 Dv to get to Mun or Minmus, land, and return.  Due to lower gravity, TWR isn't as important for a lander, it's kind of difficult to be too heavy if you've just got a pod and science, as even a single 909 will land it with ease.  Minmus is an easier landing, because lower gravity.  Despite being so far out, the burn to change orbit isn't bad, and the landing is MUCH easier, as is the takeoff.  The tricky part is the inclination.

assume five thousand m/s to get out of the atmosphere and run with that. how you apply it is a software rather than hardware problem as long as twr is above 1.1 - since the guy's already getting a plugin which calculates twr, the Dv available is just a click away

Escaping atmosphere is really weird with TWR and Dv.  I very regularly get to Mun, land, and return with about 4,500Dv, because my lifter is small and gets about 1.8 TWR.  The faster you can leave atmos, the less fuel you need getting your TWR closer to 2 can increase your efficiency a lot.  I experimented with some LT30's getting that lift, but when I replaced them with 909's for more Dv and closer to 1.1 TWR, I ran out of fuel way too early.

While you CAN get to orbit at 1.1 TWR, this is a method to get extremely large ships with extremely large fuel tanks that get shed before even leaving atmos.  Making orbit is a lot different than any other space travel - removing fuel tanks can make your ship go further.  Adding a few radial thrusters on a large orange tank can work better than asparagus big orang tanks, if you do things just right.

[Canisaur]

I've landed on Mun and Minimus, but I built a heavier rocket to try to get a real rover up there (that's what I meant when I said 'lander' in my last post, no idea why I said lander instead of rover).  Basically I increased the main shaft to Rockomax parts and attached 12 boosters using structural pieces.  That didn't work, so I doubled the amount of boosters.  It was basically a Rockomax Skipper with 24 boosters attached 

Needless to say, that didn't work much better.  I realize I could simply look up lifter designs but half the fun is designing your rockets!

Also, counterbalancing a side-mounted rover is hard.  I'm almost tempted to just send two rovers up because it'd be easier than trying to stop my rocket from immediately arcing to the ground 50 feet away.  I guess I should just tack it on top, but it looks so... terrible that way.

[LordSlowpoke]

SRBs are used primarily to get you out of the thickest part of the atmosphere. If you're using SRBs in space for actual non-messing about stuff, you're doing it wrong. horribly right.

boosters are the most kerbal of any propulsion methods

the only thing that could possibly be more kerbal is an engine made exclusively out of struts, and fueled exclusively by struts, prone to overheating when looked at wrong and with a 90% chance to spontaneously evolve a gimbal vectorer that you can't control just to spite you and everything you love

i want an engine made out of struts now

Search the KSP forums for "FTL Egg".

sweet mother of science

now i know my preferred way of getting crew up to my space station

just need to load it up with landers for when they need to get back down

[Aseaheru]

There isent really a way to control it......

[Putnam]

You know, I'm really not sure what to make of you sometimes Silly Putty.
On the one hand, practically everything you post is a sarcastic, sometimes almost scathing response to a simple, easy-to-do mistake on someone else's part.

But on the other hand, you do it so goddamn well.

oh... 

I really don't like scaring people off.

At least I'll take the compliment

[TheBronzePickle]

One thing I've been curious about is why high explosives, say nitroglycerin, have never been used as a rocket propellant. It seems like it would have a really good thrust-to-weight ratio, and lord knows kerbals would never have a problem with it. Until it exploded.

[Putnam]

Liquid hydrogen and liquid oxygen works so much better.

Solid fuel rockets pretty much are those anyway. The earliest rockets made by the Chinese were done with gunpowder.

[Sean Mirrsen]

The problem with explosives is that they explode fast. Dilute them enough to do a slow burn and they won't be all that impressive. Case in point: C4 used as campfire ingredient.

There are, however, both compounds too dangerous to even be used as explosives (FOOF comes to mind), and explosions powerful enough to propel whole spaceships as-is (Project ORION).

[Facekillz058]

What does ISP stand for on engines?

[dennislp3]

Specific impulse

http://en.wikipedia.org/wiki/Specific_impulse

[Facekillz058]

So, bigger is better?

[WillowLuman]

Graknorke just made me realize that you can push ships with EVA kerbals, and replenish the EVA jetpacks indefinitely by having them return to a command pod.

[Dutchling]

So, bigger is better?

Yup.

[Sean Mirrsen]

Higher is better, yes. Except with electricity. Electricity has no mass, so the higher the ISP of an electric engine (i.e. the Ion thruster), the less fuel is used, and the more electricity is used.

[Dutchling]

Higher is better, yes. Except with electricity. Electricity has no mass, so the higher the ISP of an electric engine (i.e. the Ion thruster), the less fuel is used, and the more electricity is used.

But don't you want that? Electricity is free, xenon gas isn't.