# Particle woes

Particles are driving me absolutely nuts! I get get it so they look just like I want them, if the emitter is sitting still, but the minute I have the emitter move along a path, then all my careful arrangements go out the window.

I am trying to make the flame coming out of a rocket motor. I have a nacelle, inside are two “burners” made from mesh circles…the emitters. One circle is parented to the nacelle and the second circle is parented to the first (I have also tried parenting both to the nacelle). I have the nacelle set to move along a path. Two things happen when it starts to move. The particles get emitted in a spiral from each successive vert in the emitter circle, rather than from all of them at once. This spiral gets “drawn out” longer than I want from the rear end of the rocket as it moves along the path.

How do I get them to emit all at once and keep the length the same? I have tried changing the number of particles (which, if the number is high enough, cuts down on the “spiral” effect), I have changed the start and stop, I have messed with the force along the axis the particles are travelling.

Also, when the rocket reaches the end of the path, the flames sort of “collapse” back into the emitter. Not so much of an issue, as the rocket is out of sight behind a planet, but still annoying.

Indeed the length of the particle trail seems to be dependant upon the rocket’s position along the path as it travels. I would prefer not to set the IPO of the path to linear, tho this seems to help a bit.

As a further problem, since I have two emitters parented to the rocket nacelle, sometimes one of them gets “left behind” as the rocket travels. Very weird.

Is what I want to do impossible? Or do I just totally not understand the particles system?

The particles get emitted in a spiral from each successive vert in the emitter circle, rather than from all of them at once.

Set Keys to 1.

Also, when the rocket reaches the end of the path, the flames sort of “collapse” back into the emitter.

That’ll be worse with Keys set to 1 so you need to give it an X Force.