You have to see this hilarious A-10 training guide from the 70s
The A-10 Thunderbolt II is often lovingly referred to as the "grunt of the skies," referring to the nickname given to U.S. Army and U.S. Marine Corps infantry troops. If the A-10 is the Air Force's grunt, then its pilots are gonna need some things broken-down "barney style" – that is to say, into as few basic instructions as possible.
Have no fear, the U.S. Air Force did just that for pilots who might have encountered the Soviet Union's T-62 main battle tank. In order to teach the grunts of the sky how to take one of them down, the Air Force issued this marvelous coloring book.
So right from the get-go, you can totally judge this book by its cover. Sure it's been photocopied a few times and is looking a little rough, but this is not exactly the kind of technical manual you see in film and television. The book is designed to inform pilots about just where the rounds from their GAU-8 Avenger cannon are most likely to penetrate a tank's armor – because while the A-10's main cannon is an anti-armor weapon, it's not an anti-tank weapon. Still, the rounds do have a chance of penetrating the T-62's armor, but only from certain angles.
That's what this coloring book is for.
As you can read for yourself, the idea of even an A-10 attacking the USSR's T-62 Main Battle Tank head-on is absurd. The GAU-8 rounds, even being depleted uranium, will not penetrate the armor and slope of the Soviet tank's armor. It even addresses common misconceptions from casual observers, like the idea of taking out the tank's treads. Even the armor-piercing incendiary round will simply put holes in the tank's tread.
Also, try finding an Air Force manual that personally insults the pilots these days.
This diagram shows what to do when the tank's crew – a crew of pinko commie atheists – is outside the hull of the vehicle. The answer is, duh strafe those swine! As for hitting the tank from the side, an A-10 pilot isn't going to have much luck getting through the turret that way. But he could penetrate the side plates, and there's always the possibility of hitting the tank from directly above it.
The whole point is that the GAU-8 Avenger isn't going to be effective if a pilot just swoops in from whatever angle he wants. He's got to hit these pinko swine from a specific angle to penetrate its armor, just like any of the armor troops on the ground.