I prefer the P-38 for ground attack, mainly because the lack of torque effects makes it easier to line up, and it carries 10 rockets, 2 1000lb bombs and has a cannon.
In theory, the best approach is a 90 degree dive, firing/dropping straight onto the weak top armor of the vehicle. In practice, though, try to get behind the vehicle (if strafing a flakpanzer, have someone make a fake attack, breaking off as soon as he's fired on, while the real attack comes from the opposite direction). Fire before you see the range markers, and break off in time to avoid hitting the ground and/or overshoo the vehicle, giving him an easy kill. Fly away on full throttle and WEP, jinking and twisting until you're out of range. Repeat if necessary.
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Rickenbacker (Ricken)
-ISAF-
the Independent Swedish Air Force