Atomic Engine Explosions

[ohlookabirdie]

ok, so i have another problem for you guys to help me with (seems i have a lot these days)

this these pics show the top 2 stages of my rocket

(click for full size)

when i hit the space bar to drop the 4 liquid fuel tanks and activate the 8 LV-N Atomic Rocket Motors something explodes and i lose 7-8 or the engines (varies with different attempts)

i cant see what im doing wrong so maybe you can

Please help

Thanks

[Cranium]

Your problem is the shrouds on the inner engines. They eject outwards, so they will collide with the outer engines. Why do you need so many engines for such a small payload? You're getting awfully inefficient with that many engines.

[Kasuha]

There are two visible stitches on each shroud, one on each side. It will open along these and the two parts will go apart with quite a bit of force. So you need to rotate your engines so the stitches are sticking diagonally out. Then they will collide to each other and your engines will stay intact.

Use Shift+Q/E to rotate your engines in VAB in increments of 5 degrees.

[ohlookabirdie]

its not got any payload

its the engine module for a bigger Eve ship (but isnt part of ksp designing insane/silly ships?)

and thanks, i didnt know they went out.... i'll have a rethink

Edited November 6, 2013 by ohlookabirdie

[Smidge204]

Very similar to the problem discussed here, including a fairly clever solution.

You do not need that many engines, even for going to Eve. You can ditch half those engines and keep the same amount of fuel and probably have a better interplanetary craft overall.

Also, most of those reaction wheels are a waste - with the arrangement you have, five inline reaction wheels != 5 times the turning power. Less is more, especially since you have RCS installed. There's also no source of power for those reaction wheels so they won't work with the engines off... AFAIK there's no internal energy storage on them.

=Smidge=

[Zephram Kerman]

Who else came to this thread expecting little mushroom clouds?

[SRV Ron]

Way too much dead weight in LV-N for what fuel your are carrying for them. You could use LV-909s, make up the weight difference with added fuel, and get better performance as the fuel gets used up.

As others have stated, the shrouds blowing off during staging are causing the loss of the engines. Rotate them 45% so they miss the engines while hitting each other.

[Jestem]

If you use the extended decouplers that hold the external engines a good distance away from the central core, then you will not need to mess around with changing the orientation of the fairings in order to allow the engines to fire without damaging each other.

Interestingly enough, it looks as if you are using the extended decouplers already. Seems odd as I have only had the problem you are describing with the decouplers that hold tanks much closer together.... Perhaps try moving the external engines down relative to the main craft a little, sometimes that might mean that the force is contained by the sturdier fuel tanks....

[Blue]

If I was building this rocket, it would just be one orange tank, some batteries, some solar panels, a large docking port, and one nuclear engine. The whole thing would be built upside down on top of the launcher rocket, so that I wouldn't have to worry about the L-VN's decoupler shrouds.

In order to bypass having gimbal confusion, the interplanetary vehicle's control pod would also be upside down, like the payload, but the launcher would have its own control pod which would be mounted upright. Right before launch, I would select the launcher control pod and click "Control from here".

Who else came to this thread expecting little mushroom clouds?

I did.