RK4 Solver Issue: Shoot the Moon with C Program

[Illuminati]

Hey Folks,

So I've been making an 4th order Runge-Kutta program for finding a way to shoot the moon with a spacecraft . However for some reason the RK4 part of the program does not work and I cannot figure it out.

I've written it in C and attached the file. If someone who is more well versed in C could take a look at it and let me know what I'm screwing up I would be greatly appreciative.

Thanks!

Edit: I've attached a couple different methods to this post. If viewing try using shoot_the_moon3.c, it should have a working .plt file to output a .png of the data

 

[Illuminati]

I suppose I should add that the spacecraft is supposed to have some kind of circular orbit, instead it acts more like a massed spring

it might be an initial value problem