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[Sirus]

No need to be pissy <_<;

I'm not even on a computer that can run KSP right now. I'll have to have your post up in front of me for reference, so I'm skim-reading.

[forsaken1111]

I kinda glazed over most of that explanation (especially since I have no desire to use MechJeb and basically just wing my flights) -- but what is the point of the yellow multi point connecter if you can't dock with it?!

Wow. Why bother asking a question if you completely ignore the answer? I only used MechJeb to show thrust to weight. There are a lot of features that Mechjeb provides that don't involve it flying for you.

Hopefully that helped someone, because I put some time into.

I read it and found it helpful. it changed the way I do my rocket planning. Thanks for the write-up.

[GalenEvil]

So... to make sure that I have understood this:

* TWR needs to stay above 1.0 to get liftoff
* TWR = Thrust / Weight; Is this as kN / Tons?
* Are all of the weights for parts given in tons? So a 1 unit weight = 1 Ton?

If that is all correct then I should be able to make more efficient rockets

[da_nang]

I think it's more likely to accelerate at higher altitudes due to lower air density so you should switch when the air intake approaches critical levels.

EDIT:

So... to make sure that I have understood this:

* TWR needs to stay above 1.0 to get liftoff
* TWR = Thrust / Weight; Is this as kN / Tons?
* Are all of the weights for parts given in tons? So a 1 unit weight = 1 Ton?

If that is all correct then I should be able to make more efficient rockets

*Yes, that's plain old Newton's second law with zero drag.
*My physics teacher would have you beheaded for mixing Newtons with tons The thrust given by the engines are in Newton and the mass is in tons IIRC so if you multiply it by 10 (really 9.81 but dividing by 10 is a good worst-case) you get the right numerical value for the weight.
*They should be in tons IIRC. But Ton != Newton

[Supercharazad]

So... to make sure that I have understood this:

* TWR needs to stay above 1.0 to get liftoff
* TWR = Thrust / Weight; Is this as kN / Tons?
* Are all of the weights for parts given in tons? So a 1 unit weight = 1 Ton?

If that is all correct then I should be able to make more efficient rockets

Yes, sort of and no.

A TWR of 1 is just enough to balance out your rocket against gravity, and any higher will send you going up.

Weight is measured in Newtons and Kilonewtons, not Kilograms and Tons.

The weight units are given in Kilonewtons, which at sea level on Kerbin is around ten times the mass (tons/kilograms)

[GalenEvil]

Okay, I was 'almost' right, so I don't feel horrible Thanks for clearing that up for me

[Funk]

for shear Thrust-to-weight ratio the tiny Rockomax 24-77 is nearly as good as the main sail, and is a lot easier to mount (it need to be as it will take 75 of them to mach 1 main sail)

[Vattic]

Hopefully that helped someone, because I put some time into.

Helped me too, cheers.

[Fikes]

I honestly couldn't even guess the TWR of things in game without MechJeb. As far as I remember KSP only shows Mass. But like I said, if you don't want to use that you can always experimient with tall rockets and single engines.

[sneakey pete]

A lot of it for me is intuition and a good understanding of physics. that and just building stuff and seeing if it works.

edit: I found out the issue with the weird off balanceness of my space plane. For whatever reason, 18.2 makes the fuel lines that are symmetry attached draw fuel from one tank first then the other. Result was one heck of an unbalanced space plane, when i had one almost full tank of fuel on one side and an empty one on the other.

[da_nang]

I honestly couldn't even guess the TWR of things in game without MechJeb. As far as I remember KSP only shows Mass. But like I said, if you don't want to use that you can always experimient with tall rockets and single engines.

Max Available payload mass = 0.1*Net Thrust of all engines - Net mass of engines

I always use this simple formula to help me design, where payload mass is the whole rocket's mass without the engines. Still doesn't account for drag, but that makes it more complicated.
E.g. a single LV-T45 engine gives you 0.1*200 - 1.5 = 19.5 (tons) of available mass. Any more than that and your TWR will be less than 1 (not really since we divided by 10 and not 9.81 but it's better to be safe). Of course, you want to aim a little bit less than 19.5 or it's going to take a long time to accelerate up to high velocities. In this case, it's roughly four FL-T800 tanks and a Mk1 command pod.

[LordSlowpoke]

alright first rocket in 0.18.2 was supposed to take me to orbit, it took me to eve rather well

do you know the feeling you get when you've been sitting there doing manuevers for twenty minutes and then the split second you look away to check where exactly you've landed your ship notices you're on sloped land, tips over and explodes

going to need lander legs for once.

[Guardian G.I.]

This is a stupid question, but can someone upload MechJeb version 1.9.6 to a file-sharing website, so I can download it?
KSP official website, KSP Spaceport and official forums are off-line (at least for me). Found it elsewhere, never mind. KSP official website is still down, though.

[GodlyTeapot]

Well I landed on the Mun today.


I am pretty damn proud of that. I know it's not much compared to what most of you guys do, but you've gotta start somewhere right? Minmus is next in my sights, any advice? What's the gravity there like? Shall I tell Jeb to pack more or less landing fuel? I mean, I know he won't listen, but I feel I should tell him to do SOMETHING.

[Sirus]

Gravity is quite a bit less, IIRC, so you won't need as much fuel to slow down/take off again. If you want an easy-ish landing, aim for the blue areas of Minmus; it's basically a frozen ocean, and thus very flat.