I'm new to SCP, but I've been playing FS2 more or less consistantly for over 6 years. This is what I've noticed about using missles. Getting the missles to work requires finesse. A lock doesn't guarantee a hit. You have to have some good distance between you and your target and the target needs to be heading either away from you or straight towards you. There's a sort of 'sweet spot' were the enemy is in a prime position. If he's turning sharply, the missles will lose track. What I usually do is follow behind. The target is usually turning in one direction, but eventually the AI will stop turning for a brief second before it starts another manuever. This it does to throw you off. If it's turning upwards, you'll pull your joystick upwards hard to keep up. Then it'll do a quick stop and turn the other direction. If you're not paying attention, you'll be thrown off and he'll go off screen and you'll lose missle lock. If you're quick, you'll stop too and the instant he's transitioning from turning one way to turning the other he's relatively flying straigh for a brief instant. If you fire your missles here, when both you and the target are flying straight your missle are pretty much guaranteed to hit. He'll try to evade, but he usually won't be able to gather enough angular momentum to be succesful. I tried with both my harpoons and hornets just today and while hornets are slower and not as effective as tornadoes, they still seem to work fine like this. However, I've never really used the rockeye. They were always useless except against bombers.
