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From: (CDB100620)
Subject: Re: Flying Tigers /P40
Date: 22 Apr 1998
Newsgroups: rec.aviation.military

>This convergence point of the fire-streams was, I believe, set to be
>roughly up to half a mile or so in front of most of the WWII fighters

USAAF doctrine called for generating a "lethal density pattern"--the most
bullets passing through a given space in a given time.
But the AAF was also concerned with the less than remarkable gunnery of the
vast majority of fighter pilots.  So the official recommendation was to have
each pair of guns boresighted to converge 100 yards beyond the previous.  A
typical recommended pattern for a six wing gun figher would be 250 yards for
the first pair, 350 yards for the second and 450 yards for the third.  That
way, it was figured, the bad shot would have a chance of getting at least some
In the field, this was generally considered to be complete nonsense.  Your best
chance of shooting someone down was by catching him by surprise and squashing
him like a bug on the windshield of a Mack truck before he had a chance to
react.  If you managed to sneak up on him, but then just tapped a handful of
tacks into his tail feathers, all you'd do is piss him off and tell him where
you were.  And if you couldn't shoot him down when he was cruising along with
his thumb stuck up his ass, you sure as hell weren't going to shoot him down
when he had his dander up and was doing everything he knew how to shoot you
So fighter groups stuck with the lethal density pattern.  The rule was, the
worse shot you were, the closer in you moved before you opened fire.   Most 5AF
fighter squadrons flying wing gun planes boresighted all the weapons for 200
yards, but some squadrons boresighted them for 100 yards.  As new pilots were
told when joining a squadron,  "If you can't goose the squint with your
spinner, you're too far away."
Whether boresighted for 100 or 200 yards, with the rounds from every gun
passing through an 18-inch square, a brief burst was all that was needed to
finish an opponent--if you hit him.  Thus the insistence on closing in to
"can't miss" range.  That was, of course, easier said than done, taking a great
deal of flying skill, self-discipline--and guts.

From: (CDB100620)
Subject: Re: Flying Tigers /P40
Date: 22 Apr 1998
Newsgroups: rec.aviation.military

> This is an
>"all or nothing" strategy, either the opponent is shot down or he
>gets away (almost) unhurt. Of course the aircraft of the 5th AF
>outflew most Japanese fighters, so if they missed they could get
>away safely.

That's largely correct, although both the Tony and Tojo could stick with the
AAF fighters pretty well.  Bore-sighting at a set--and close--distance was a
strategy for attacking fighters.  It wasn't that great for attacking bombers
because it would be a very brave man who could close in to within 100 yards of
a formation of bombers before opening fire.  And if he were making a head-on
attack, he would have very little hope of doing any serious damage except by
sheer luck (this is one reason why a flight of P-40s would make a line-astern
attack on an individual bomber--hoping to increase their chances of hits).  One
reason the P-39 or P-400 was a better anti-bomber weapon than the P-40 was the
concentration of nose guns, Me 109-style.  In a head-on, the P-400 (two .50s
and a 20mm in the nose) could open up beyond maximum effective range (1,000
yards) and keep the guns firing on a chosen target for perhaps a full two
seconds (closing speed around 700 feet per second) and expect to hit it for a
sustained period (relatively speaking) if the aim was good.  A P-40 driver
would do the same thing, but except for one very brief instant, most of his
rounds would not pass anywhere close to his aiming point.  But if, by skill or
luck, he had his sight planted on the bomber's cockpit when the bullet stream
converged--Wham!--good-by bomber.  But to hold steady on a bomber approaching
you at 700fps (combined closing speed) until you were less than 300 feet away
and only then twitch the controls to avoid a collision....  Need nerves of
steel and reflexes like a striking rattlesnake.
The way the Luftwaffe boresighted guns seems like a good compromise for the
mission they were tasked with--primarily attacking bombers but also sometimes
dealing with fighters.
Once in a while, a rear echelon brass hat expert would swing by a squadron and
try to convince the CO of a P-40 outfit to try a line abreast attack on
bombers, the reasoning being that all those bullets flying every which way were
bound to hit some bombers, even if they weren't being aimed at, and if the
damage forced them out of the formation, then they could be dealt with in a
more conventional fashion.
The problem with that idea (even if it would have worked) was that Japanese
bombers were hardly ever unescorted, and as soon as the Japanese fighter pilot
sighted his foe, he attacked.  No way a gaggle of P-40s could mosey around
getting themselves arranged in a line abreast formation.  They had to
immediately shoot and scoot or start cheek-to-cheek dancing with Mr. Moto and
get their toes tromped on.
In the SWPA, another one of the many reasons the P-38 was so well liked was
that the boresighting problem didn't exist.  It was equally adept at attacking
bombers or fighters, the concentrated bullet stream available from maximum to
point-blank range.  But even with the P-38, the rule was, close to point-blank
range before opening fire to ensure a kill.  Circumstances, of course, didn't
always allow this.

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