Well, I have no idea what’s wrong with your file, but I removed the Particle System and then added a new one with (as far as I could tell) the same settings (not a copy…) and it seems to work as expected now:
https://www.dropbox.com/s/h7xxfwinst6gtzt/LowPolyRocketSchofield1_fixed.blend?dl=0
Let us know if there is any problem…
I did notice that for some reason there is a huge difference in file size, again, no idea why;)
