Shortround6
Major General
The wind velocities are much lower but the air density is higher. At 20,000ft or so the air density is about 1/2. the bullets slow down less due to the lower drag and and ability of the same speed wind would be roughly 1/2 also.These articles are discussing rifle and pistol rounds fired at ground level where wind velocity is most likely much less than at the altitudes our aerial warriors are playing around in.
We may be worrying too much about minor details. In the example given by Sierra they are talking about a change in impact of around 3 feet at 600ds with the just over 10mph wind example. about 1 man in 1000 (or less) had any business at all it shooting from one airplane to another at 600yds in WW II. If I am right about the difference in air density then even a 40mph wind at 20,000ft is only going to move the bullet about 6 ft at 600yds.
The major problem was figuring out where the target was going to be when the bullets reached it. A 300mph airplane is moving 440ft a second or so. If the bullets take 0.5 seconds to reach the target the target has moved 220ft in that space of time. Even if you are in a plane doing 300mph and aiming at a plane doing 300mph that is even a little of to the side of 6 o'clock you need to shoot at where it will be and not where it is.
given some of the less than precision sights most air gunners had to work with aiming was more a matter of 1/2 a plane length or so (against fighters) than really particular spots. Tales of aiming for oil coolers notwithstanding
On the ground a rough rule of thumb for cross winds is if the distance is doubled the wind drift goes up be around 3.5 or 3.6? I have forgotten but it is a bit under 4 times. Dispersion due to range also goes up with the square of the distance. As in if all bullets had landed in a 20 in circle at distance A then all bullets should land in a 40 in circle at distance 2A, at first look it seems to be doubled but the target area is actually 4 time bigger. If the intended target is only 10in in diameter what are the chances of hitting it?
This why a lot of aces said to fill your windscreen with the target plane or when you thought you were to close to get closer.
British thought that a power operated mount increase the effectiveness of a gun by between 2 and 4 times.