unfortunately... the bits in game studio i use

aren't A7
aren't physics
and aren't planes and missiles :P

couple of ideas though,

when you call a new function you should really pass things through it in the parameters to make sure it's still calling the right entity, i'm not sure if A7 does/doesn't return errors for this,

Code:
action ball_drop()
{
while (key_space == 0) {wait (1);}
phent_settype(my, PH_Rigid, PH_box);
phent_setmass (my, 2, PH_box);
ph_setgravity (earthgravity);
phent_addvelcentral(my, vector(0, -472 * cos(launch_angle) , 472 * sin(launch_angle) ) );
missile_flying(me);
wait(1);
}


Code:
function missile_flying(localEnt)
{
me = localEnt;
while (1)
{
my.roll = my.roll + 3;
wait(1);
}
}

try that?

2ndly, i don't know if playing with physics prevents you doing any other object manipulation? maybe someone else could answer that

3rdly, if your missile is symetrical all the way around, then you wouldn't necessarily see if .roll is working? try it's .tilt see if that makes it obvious

just some suggestions but doubt they matter? smile