Tony Williams
Airman 1st Class
as for Yak-9T, NS-37 has both shells, OZT (frag incendiary tracer) and BZT (armour piercing incendiary tracer)
I know that the gun could fire both types, but that is not my point. The Yak-9T was used by fighter units, who would have been issued with HE shells. I have seen no evidence that these units were issued with AP ammo.
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