I’ve found the best tacticts to be trying to engage with the altitude advantage and then draw them into a single circle fight and get them to bleed as much speed as possible, bring both your speed down to the 190-210 km/h range with takeoff flaps and WEP. If you have altitude, cut your engine and try to start the downward spiral double-helix thing (i forgot what it’s called, but I’ve worked miracles with it)
If you’re out in front of the opponent when engaging then you’re kinda cooked, but try to force an overshoot and do NOT follow into a climb fight.
On the head on, try to fire early. They won’t expect to see the sheer volume of rounds the 12x7.92s can put out and unless they’re fully committed they’ll pull off, be ready to catch them when they do so.
Never try to out climb and diving for an enemy is not ideal.