50 Amazing Facts About The A-10 Thunderbolt Heaviest Front Auto Cannon The 30 mm GAU-8/A Avenger sits in the front of the aircraft, with the barrel protruding from the nose of the A-10. It is the heaviest automatic cannon ever mounted on an aircraft. Up Next: More amazing facts about the A-10 Pages: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50