well dux, if you stall your plane in a hammerhead and flip the plane downwards (less than 50mph) and fire rockets when rudder is applied, the rockets go straight down, not where the nose is pointing.
Rockets have propellant, where the nose is pointed means the rockets are pointed since they are fixed to the wings. When fired, the rockets should fly in that direction (affected by the plane's vector as well of course). Thing is, the game doesnt seem to take the plane's nose direction into account.
Flat spin plane (nose pointing at horizon but plane falling straight down) the rockets go down. Get shot down with your rockets still on (read: P-38 has tail booms blown off), your plane spins downward, nose going up and down up and down... when nose up, fire the rockets. The rocks will fire straight down the plane's vector (aka, earthwards) , not where the nose is pointing (aka, skywards).