If you are a sub player then you have probley experienced your sub not following
commands given. Keep in mind that your sub can only initiate an attempt to surface,
submerge or critical dive once every 3 seconds. Key word attempt....

If your under heavy fire and taking damage your ship may refuse to submerge even
if it attempts it, it will just surface again right away...

If your almost out of air say 5-10% air remaining and you attempt to critical dive,
your ship might refuse to crit dive....

My only solution to the above referenced problems is to spam dive and critical dive
buttons atleast 5 times if you want to be sure...

Be sure to change defaults U & I to U and O so you dont accidently press the wrong
button in the heat of battle...