"Combat Damage Assessment Team A-10/GAU-8" Topic

Combat Damage Assessment Team A-10/GAU-8 Low Angle Firings Versus Individual Soviet Tanks, February-March 1978, Volume 1, Air Force/56780/February 2, 1979.

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In this test an A-10 aircraft attacked two combat-loaded individual Soviet T-62 tanks in five missions totaling seven passes; technicians rehabilitated the two vehicles after each pass. The aircraft were seldom higher than 200 feet in altitude; firings were initiated between 2768 and 4402 feet and terminated at ranges of 1587 to 3055 feet at dive angles of 1.8 to 4.4°. The bursts ranged from 120 to 165 rounds.

Altogether 93 DU rounds struck the tanks during the seven passes, including no impacts on one pass. The ratio of impacts to rounds fired was 0.10. Of the 93 impacts, 17 penetrated the armored envelopes for a ratio of perforations to impacts of 0.18. The report noted many of the side or rear impacts that did not penetrate the armor nonetheless extensively damaged the tanks' exterior suspension components, whereas all the rounds that hit the tanks' front caused minimal damage. These results reinforced the strategy of attacking tanks from the side or rear to optimize damage potential.

The situation doesn't change if you try the high angle attack -- from that position armour have better abilities to resist the penetrating rounds because of 30-45 degrees angle, while low-angle fire all shells going up 90 degrees to the side-hull and side-turret of the tank and have much better penetration ability. So this concludes, that GAU-8 have no any chance to bring even serious damages, but only could make alone tank immovable, if all fire power goes to the engine hull area from rear with the high angle attack.

In Iraq difficulties were encountered by the A-10. Its most fearsome weapon—the 30-millimeter (mm) cannon—had to be fired at more than double its normal slant range and suffered in accuracy and effectiveness. Combat engagement parameters are rarely ideal or like on the firing range.

I'm personally a big fan of the A-10. Of course, this assessment does not account for any additional effects like suppression, damage to optics, etc. A big problem in Desert Storm was the ROE had them operating at 10,000 feet and revetments that had fake targets looked like real ones and lit on fire when hit. If the current air situation like Ukraine persists I don't see the A-10 doing anything other than launching missiles.

Wolfhag

What about against infantry and lighter armor?

The A-10's big advantage has always been its ability to use smart munitions, both missiles and bombs. The gun looks impressive but tends to be harder on friendlies than the enemy.