In relation to your first question (HO pass with con below you), it sounds as though you are diving below his altitude when you split S. If you are split-Ssing (is there such a word?) at high speed, remember that you will make a HUGE turning circle. If he sees you coming down, and starts a zoom climb, you'll probably pass beneath him at high speed, all he has to do then is roll inverted, dive after you and kill you when you try to recover.
So, Rule 1. If you're gonna split S, make sure you have the room to do it
In a fighter like a P47, P51 or 190 I would never think of doing a split S on a lower fighter unless he is at least 2000 feet below me, preferably more.
Rule 2. Don't split S when he's directly below you. Your approach angle will be awfully steep, inviting you to overshoot below his altitude if you miss the shot. Instead, fly straight ahead until he's about 1500 yds behind you, then split S. If you drop a little below his altitude, don't worry.. you'll be going like a bat out of hell and gaining on him. Stay slightly below his altitude until you are near guns range, then begin a gentle climb to take your shot. This does two good things for you.
1. Since you are already climbing slightly, if you should happen to miss your shot you can do a low g 45 degree zoom climb above him and regain your energy.
2. Since you are coming from low to high, the enemy will most likely make a nose low turn to evade your shot, burning off his own energy.
OK, in relation to your second question (excess speed on the dive), cut throttle, barrel roll on the way down (a nice little energy burner) or do mid G 'S' turns on the way down to control your closure.
Best advice of all? Drop by the TA some time and watch someone else fly the moves. Ride as an observer for a couple of hops and see how other pilots fly in the same situation.
Hope this helps.
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C.O. Phoenix Squadron
http://www.users.bigpond.net.au/phoenix'feel the heat .......'
