Originally posted by rshubert
Nice try, G, but the plane was passing left-to-right approaching from behind, at D400 or so, according to F4UDOA's original post. I would get five seconds at him from that approach vector if I saw him coming.
4.0k identify threat...1.6k aim...1.0 k open up...stop when he flys past.
Nice try R

You'd be hard pressed to see a fighter head-on at d4k to say nothing about identifying it. You start aiming at d1.6k a
mile out? ... and you start firing at d1k. By that time you have been attacked by the other fighers you didn't see while aiming and wasting your ammo at d1k.
Here's a little anectodal evidence for you:
The Schweinfurt
Raid
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By Sgt. WALTER PETERS
There were fighters everywhere, but mostly on our tail. "The whole Golly-gee Luftwaffey is out today," somebody said over the inter-phone. There were the single-engined Me.109s and twin-engined Me.110s; there were Ju.88s and FW190s; there also were Me.210s, even Dornier bombers, and God only knows what else the Germans had thrown into the fight. The only things they did not throw at the division were the plane factories themselves, or such factories as they have left to throw.
"This is nothing," Zorn reassured me. "We've seen worse in other raids. About 25 minutes more to the target."
The captain took a little evasive action. The plane banked to the left, then to the right. To the right we sighted a huge column of smoke, which looked at first like a big black cloud. It was the target. Libs and Forts had already passed the ball-bearing works and hit the plants solidly. We'd soon be there, but we wondered just how soon. The passage of time is a little different up there. The Navigator told me to look out of the left side. There were a couple of planes burning there, a Fort and an enemy fighter. Three white parachutes and one brown one floated in the sky. The whites belonged to our boys. Under the brown one was a German.
When in hell are we getting to that target? Time has passed so slowly these past 15 minutes. Ten minutes more and we'll surely be there. Heuser was still calling them off. The fighters were coming in from all sides now, but not too close. Maybe about 500 yards away, often as much as 1,000. I looked back toward the fuselage. There was Tex, his left foot planted on a box of caliber 50s, his right foot lazily dangling in space. From the inter-phone we knew Tex was a very, very busy top turret gunner. His gun was tracking fighters all around the clock. Occasionally he concentrated his gun to the tail, where his friend Sweeney was busy firing at the enemy as they queued up from the rear.
A Ju.88 and a 190 attacked Sweeney's position from 4 and 8 o'clock, and high. Tex's guns worked fast. Both planes peeled off. The 190 shied off but the 88 came back from about 500 yards to the rear, flying smack into the ex-tire salesman. Sweeney calmly pressed his triggers. Meanwhile, Tex directed his fire. "You're shooting at him just a little high. Get him lower. A little lower." Sweeney did; the 88 came closer, and lobbed out two of the rockets which the Germans are now using. They were deadly looking affairs as they shot out like flames.
Tex still guided his pal over the inter-phone. "A little lower, Bill," he said. A little lower Bill went. The 88 wavered, flipped over and as it did we could see that it was afire, trailing smoke. Then there was one less Ju.88; also one less Ju.88 crew of two. They didn't get out.
---
These guys had trouble hitting a Ju88 at 500 yards steady on their six, a bloody twin-engined bomber!
The selfdefending bomber formation concept was violenty proven faulty on Oct. 14, 1943.