Originally posted by Gianlupo
Any hint about vertical convergence? I mean, when you have a mix of mg and cannons, how do you have to set convergence in order to make sure that bullets and shells hit in the same spot? Cannons convergence has to be set longer than mg?
You are refering to harmonic convergence. The harmonic convergence automatically coincides with your convergence setting. The problem is that on a moving target, the flight time to the target is generally going to be longer for cannon than it is for high velocity machine guns. And generally speaking, MG's will reach the target before cannons. In some situations that can cause the cannons to hit farther back on the target.
In many airframes this is irrelevent. In many cases, pilots only fire both MG's and cannons in very selective instances, and rely on each weapon set individually for different circumstances. What it comes down to is how
you tend to use your guns in a specific airframe. For instance, in the 38 I mainly use .50 cals, and only use cannons with .50's on 'sure shots'. In that instance, I have the 20mms set about 200 yards farther out to adjust for the flight time difference. No harm done in setting it that way because all the guns fire from the center line. On the 109 with a centerline cannon, I usually also set those slightly longer.
In the spit, I use guns the opposite way, firing mainly with 20mm's and only using both on a 'sure shot'. In that instance I leave convergence the same on both weapon sets.
My point is that before changing your convergence on cannon, evaluate how you use cannon vs MG's in that particular plane, and also take into consideration how far off centerline the cannons are mounted. In many cases the projectile 'flight time to target' dilema is low on the list of priorities...but in some instances, it is worth taking into consideration.
