What do you do when you don't have enough fuel/lift?

[Dewm]

So I have a payload, that I just want to get into simple orbit around kerbin. Assuming my payload isn't game breaking (which I don't think it is) What is the best way to get it into orbit?

I tried surrounding it with rockets and more fuel tanks etc etc...

but I get to around 40,000 meters and I don't have enough fuel to go further..should I get more engines? should I get more fuel? should I do both? maybe more boosters?

Right now I am hitting 150m/s at around the 5000 meter mark.

Anyways.. wondering, what is the best way to go about this?

Thanks!

[MockKnizzle]

Are you by chance trying to go straight up?

[stupid_chris]

Unless it lowers your TWR too low, always get more fuel. More engines is going to make you go less far, another booster would be necessary if you can't add more fuel because you won't take off.

[Tiron]

Well, without knowing much about your rocket it's hard to say. You could have too little TWR or too much, not enough fuel, too many inefficient engines, inefficient staging arrangement... Some screenshots of the craft would be helpful, and yes, some words about what kind of flight profile you're using.

[CaptainCrunch]

Can you post a screenshot of your launcher?

EDIT: What that guy above me said...

[Captain Sierra]

For starters, can we get pics and stats (especially weight) on the payload and launcher? .craft files would be nice too. Also, what kind of staging are you using, what kind of engines, where are you starting the gravity turn? The more you tell us, the more we can help you. Believe me, the KSP community is one of the most helpful game communities I've ever seen. More info you give us, the more answers we can give you.

[Tiron]

Data, data, data, we cannot make bricks without clay.

Apparently quotes, even if they're not actually quotes of a post in the thread, don't count for 10char.

[Whackjob]

Rule #1 of KSP: Moar boosters.

Rule #2 of KSP: Moar struts.

Rule #3 of KSP: When you must, asparagus. Never be too proud to put yourself above a vegan launch. In KSP, it's the destination, not the journey. Mostly.

[SebLavK]

With 150 m/s at 5000m with full thrust, it seems like you have too little TWR (though you can manage to make very efficient lifters that achieve the optimal speed for your altitude with little throttle correction, eg. an orange tank with an LV-45 at the center and four Aerospikes with a 5t payload)

See this for a table with terminal velocities at Kerbin atmosphere

Usually, if after making my gracity turn at around 10,000m my velocity doesn't increase quickly I know something's wrong with my rocket.

Also, if you're familiar with the rocket equation, and you think your payload is too big, you could always try to split it in different parts and assemble everything in orbit. That's always a nice challenge.

But basically, we need to know what everybody's been asking so far;

-What staging are you using?

-What is your payload?

-How are you flying the rocket, when do you do your gravity turn?

-Could you produce a screenshot or a .craft file?

And if in doubt, MOAR struts, MOAR fuel and MOAR SRBs never hurt.

[Tripzter]

Add more orange tanks with the cruiser engines. Reality is you already have enough thrust to tare the joints so add the 650 thrust engines to the outside tanks. My rule of thumbs is if you're bellow that 60some % throttle mark, add the 650 engines.

[Dewm]

So here it is. Like I said, I get to 150m/s at around the 5000 meter mark. And I get a grand total height of around 40,000 meters.

I burn up to the 10,000 meter mark. then tilt it around 30 degrees.

[Tripzter]

Add more tanks and add some cones to your orange tanks.

[stupid_chris]

Where are your fuel lines.

Also, since this is turning into a help thread, moving to the gameplay questions forum.

[SRV Ron]

Place Rocomax X200 8 fuel tanks under each Mainsail to prevent overheating. You do need more solid fuel boosters to get this to over 5,000 meters before burnout. And, it does look like too much payload for the lifting power available.

[Dewm]

Where are your fuel lines.

Also, since this is turning into a help thread, moving to the gameplay questions forum.

Well I just wanted general help. I have this problem with other ships as well... So I would gather.. more fuel is best.

[Captain Sierra]

Okay, that payload is about 4 of my fuel cans. it weighs about 160 tons (mine weigh ~40). a 160 ton lift is not easy. I would advise less payload.

EDIT: if you still insist, add fuel lines from the stage 2 tanks to the stage 3 tanks. You appear to have KW Rocketry. Use the KW 2.5m (smaller of 2) 4 nozzle griffon engines. They get 1700 thrust over a mainsail's 1500.

[Dewm]

Gotcha... Hmm maybe I'll have to do smaller lifts and just more of them.. this is my current design (see below) which gets me to like 120,000meters.. but not a stable orbit. so yeah.

[AlamoVampire]

Okay, I want to ask a stupid question in this thread: where do you see how much your ship weighs in or is that a mod?

btw, this may seem counter intuitive but, sometimes more is less, you can end up in a nasty circle of: needs more fuel to lift what you have, but, more fuel weighs more, which needs more fuel to lift, and around it goes :S

[Captain Sierra]

Okay, I want to ask a stupid question in this thread: where do you see how much your ship weighs in or is that a mod?

btw, this may seem counter intuitive but, sometimes more is less, you can end up in a nasty circle of: needs more fuel to lift what you have, but, more fuel weighs more, which needs more fuel to lift, and around it goes :S

I know the weight of my fuel cans by adding up the 'total mass' value. You can get weight that way or you can get it through things like Kerbal Engineer and MechJeb. I routinely use MechJeb for build stats and for certain autopilot tasks.

[Captain Sierra]

Gotcha... Hmm maybe I'll have to do smaller lifts and just more of them.. this is my current design (see below) which gets me to like 120,000meters.. but not a stable orbit. so yeah.

<snip>

FUEL LINES! Asparagus stage that sucker!

Fuel line routing: Route the single stack ones to the double stack ones immediately to their left, route those double stack ones to the double ones on their left (that's right, on the other quad section). Route that set of doubles into the KW jumbo tanks. Remember, run fuel lines from the bottom-most tank in a stack.

Staging: SRBs then outermost singles drop first; double orange columns on the left side of black/white tanks drop; next (and last) set of double orange jumbos drop, then burn until out of gas. Under this staging, you might want to change the KW griffon motor out for I think it's the wildcat. Whichever the 3.75m large single is (NOT the one with the large round thing and small nozzle, the coneish one with the wierd yellowish balls on the sides).

[The Destroyer]

If you want, send me the .craft of the payload and send me it, I'll show you a good idea.

And tell me what mods I can use.

[Dewm]

I think i'm playing stock.. and ehh how do I send the .craft?

[Captain Sierra]

No, you are not playing stock. You have KW Rocketry. Fortunately, so do I. Assuming you are already in your KSP directory, go to the saves folder, open the one for the save you are actively playing on (or contains the ship). You will see a file: persistent.sfs and maybe quicksave.sfs and a folder: ships. open that folder. Your working in the VAB so open the VAB folder within that. Find the ship by name there and copy it out to send it. YOu can put it on any file sharing site that you can link here.

[hubertus09]

I suggest you use 1 orange tank (+ a tiny fuel tank so that the engine does not overheat) per main sail engine.