I mean this thing would be beyond impractical, right?
If I recall the largest PPSh drum magazines held about 70 rounds. And it is a very fast firing SMG with a cyclic rate of 1,250 rounds per minute. Meaning any one of those guns is gonna be empty after about 3-4 seconds.
Unless they flew over extreme concentrations of troops to target, the juice wouldn’t be worth the squeeze. Changing mags would be difficult or impossible mid flight