Tips from someone who has flown it for 6 years, training grizz to be a monster, helped sunsfan become a monster and was the king of slow during my prime. I brag I brag, but listen up.
1. Fly it about 12 K, no point in going higher unless you are in FSO. Sometimes not even that high. You can't dive much so you have to spiral dive anyway to pounce on low con's. 12k is a good alt to keep the hi and low con's in check. The plane is one of the best defensive fighters in the game so don't worry about hi P51s or 190s diving you. You can typically avoid them and they will fly away.
2. Don't fly it like a BnZ plane and don't fly it like a turn plane. It is neither, it is a slash attack plane. Make quick pass attempts as close to your opponent as you can. You have to get in close, make a shot, and get away from the rest of the enemies.
3. Learn defensive ACM If you want to be successful in the K4. The plane lloves when the enemy overshoots and sets you up for a nice 30mm 200 yards away to the face. The whole key to the 109 is to set up attacks so that the enemy plane crosses your gunsight 100-300K away. You will have better luck making quick snap shots than you will trying to make lead shots (like how you would shoot a P51 is not the same position you'd want to be in shooting the 109k, generally)
4. Most Importantly, learn to fight with vertical ACM maneuvers like emmilmans and split S. The plane excels in the vertical loops and this is how you create angles in order to make a quick deflection shot with the 30. Also learn to keep your E so that you can rope planes (very valid tactic with the K4 since it has a poweful engine. The K4 is all about creating angles. It is not an easy as a plane some would like you to think. Also to battle the tourque when you desperately have to turn right, cut your throttle (not engine) and use lots of right rudder and aileron to turn right. When you cut throttle it cuts the torque and helps you get over to the right.
Go to the DA or TA and duel people with it. This is the best way to learn the K4 as you will get in many fights like it in the MA. You have to be very aggressive with your attacks but don't get too slow right off the bat. The style of 109s is very aggressive, much like a bullshark. Get in, make the shot, and get out without burning too much E, but you have to use slash attacks to keep the enemy on their feet.
I'll post a nice 109K sortie when I get off work that you can watch, which will identify exactly what I'm talking about here and hopefully help you have better luck with it.
There are other advanced tricks the K4 can do but just practice with that first and then we will hget to the hard stuff.
Also, I set convergence at 400. The bullet is heavy and you already have to lead far, so if you make it too short you will have to lead even further than normal. 400 shoots pretty straight and is easier to see the bullet shoot.
P.S the spiral dive and spiral climb are your best friends in the 109s. Learn how to use them effectively!
