Pongo, the reason that countries used both AP & HE is that they are both important (kinetic or explosive) is that not only do you need them for different missions, but also because depending on what part of the aircraft you are hitting, and from what aspect angle different shell types would be more effective. (my own theory and opinon of course)
On dead Six shots, AP is very good because it tends to go thru many many parts of the aircraft (including armor and engine blocks) before it becomes ineffective or exits the aircraft, where HE would detonate in the tail or on the skin limiting damage to that area.
On snapshots from planform aspects its just the opposite, AP would do little damage punching in and out of the skin doing little damage(say a wing), where the HE would blow a huge chunk of the wing out.
In my opinon you would probably need both like you said.
If you or anyone else can get the typical ammunition loadout of a hispano armed aircraft I will do the calculations you are asking for, but I don't know how the ammunition was loaded for Allied planes typically.
On the 30mm Cannon issue, let me explain. Several years ago while I was doing research on lethality (and running into a lack of hard data) I met a gentleman thru my job that works for a government contracter that dealt with various munitions. He was the plant engineer, and this company took old ammunition of various sizes, "de-manufactured it" and then recycled the components and sent the material to be used in new ammunition.
So he invited me to the plant, gave me a tour, and showed me quite a few things and gave me some interesting information on light to medium caliber shells and bullets, including how they were constructed, fusing, components, and a whole lot more. While I was there they were working on everything from 7.62mm Nato rounds up to and including WWII era 40mm AAA rounds.
I told him about my research into lethality and we spent some time in his office going thru his reference library, and thats where I got the information I quoted in the earlier post. Of course all the information was for American Ammunition, but I wanted something I could compare the German 30mm shells too to get a feel for how the larger shells were loaded with explosive in relation to weight, and the shell I quoted was what we found.
I am not sure exactly sure about when this 30mm was used, but we both thought from the available information that it was from the WWII to Korea era.
Now the 20mm info I quoted this guy was confident that it was representative of WWII shells, because his factory had "demanufactured" a large number of them. But the 30mm was not something he had worked with, so it was taken directly from the manual that I referenced.
The shell could have been from anything from a aircraft gun, to a anti-aircraft gun. I just included that as a FYI type of thing.
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Vermillion
**MOL**, Men of Leisure
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