Problems with LV-T30 engine

[Fluffybacon]

Hi all.

I just started this game.

So Im trying to get my first rocket to launch in career mode.

Im using a reaaaly basic design.

Capsule with parachute and liquid fuel tank pluss the Lv-T30 engine.

Now.. When I try to launch the rocket I only hear the sound but it stays grounded.. Any suggestions to what Im doing wrong?

Best regards

Fluffybacon

[Specialist290]

The LV-T30 is a liquid fuel engine, meaning you have to manually manage the throttle for it to burn. Use the Left "Shift" key to increase your throttle and the Left "Crtl" to decrease it. "X" allows you to instantly cut it off as well.

[Taki117]

Another option is that the engine is getting stuck inside the launch pad during physics load. If you have decouplers you can put one under the engine and have it activate on the same stage as you activate your engine. If you don't have that tech node unlocked all you really have to do is put a pod on the launch pad, do a crew report, EVA and due an EVA report and surface sample from the launchpad. Then walk off the launch pad and take an EVA report and surface sample off the launch pad (Be sure you store your reports in your pod first) and you should get enough science to unlock the next tier and most of tier 2.

[Tank Buddy]

How big is your rocket? The LV-T30 can only lift ~3 FL-800 tanks.

[Dispatcher]

LVT30 has a TWR of 17.5 (to one). Its mass is 1.25 (tons). (1.25*17.5) + 1.25 = 23.125 so that's about your maximum lift off tonnage. Total up the tonnage of your parts in the VAB and see how your ship compares with this. Obviously if you exceed the tonnage, the ship will sit on the pad and burn fuel/oxidizer until enough mass has burned off and dropped the ship down to the tonnage which the LVT30 can lift.

[capi3101]

Career at Tier 0...only tank available is the FL-T200 unless I'm mistaken; a single LV-T30 should lift somewhere in the neighborhood of twelve of thems.

Make sure you haven't got too many fuel tanks, make sure flow is on for both fuel and oxidizer and make sure you've throttled up. If those are all okay, there's a bug at work.

My delta-V calculator says that with twelve FL-T200 tanks and one engine you should have 4,569.87 m/s and a launch TWR of 1.42. Obviously that's a single stage rocket and matters are complicated by the fact that the LV-T30 hasn't got thrust vectoring. Essentially you have what one forum member called a "derp stick". You'll have to fly with SAS toggled on the whole way and make any changes in orientation gently unless you want to wind up pointed the wrong way. Straight up to 10k, 45 degrees at 090 until you're 30 seconds from apoapsis, then follow the prograde marker. Go horizontal once you're a minute to apoapsis. Watch your gee meter as you ascend and throttle back if it climbs out of the green zone (ideally you want it to stay right at the top of the green zone). Stop your burn when your apoapsis is as high as you want it (plus 10k if you're around 50,000 when that happens, plus 30k if you're around 40,000 when that happens). Make a maneuver node for orbital insertion and burn when indicated. You should have enough delta-V to make orbit easily; deorbiting afterwards will require a small burn - 50-100 m/s, tops.

Try to land engine down and don't panic when parts of the rocket start 'sploding on impact. You'll be somewhere around 3.65 tonnes empty which is too much weight for a single small chute to slow to a safe speed but not so much that the chute will rip off (provided you deploy the chute early - say hit the button around 40k; it'll do its job once the atmo's thick enough). Once enough of the empty fuel tanks have blown, the rest of the craft should slow to a safe speed for landing (this from experience, BTW).

Edited December 28, 2013 by capi3101

[capi3101]

Wanted to confirm I wasn't steering anybody wrong with the advice in my previous post, so I built said craft described above and launched it this evening. Actually, I've got a mod that allows KER functionality without KER parts, and it told me that the twelve tanks would give me 5300 m/s (more than enough for an orbit and return). So I started taking tanks off; nine tanks were sufficient to get the craft into orbit with sufficient delta-V for de-orbiting (was left with 60 m/s of delta-V when everything was said and done). The landing was hairy on account of the thing started tipping over rather than land straight up and down, but the important thing is that the command pod/pilot survived.

So there you go. Launch a craft like the one I described into a polar orbit (steer north or south instead of east when you make your gravity turn). You should be able to make EVA crew reports over multiple biomes, and then once you're down you can collect a surface sample from wherever you wind up. Should be a worth a goodly amount of science and you can actually go into space rather than muck about the launchpad.