I saw an AC-130 fire in the summer of 1986, and it (pardon the pun) blew me away. I would love to meet the men and women who came up with the idea to put artillery on a cargo plane. The armament includes two M61 20mm Vulcan cannons, one L60 40mm Bofors cannon, one M102 105mm howitzer, one 25mm GAU-12 Gatling gun (baby brother of the A-10s GAU-8 30mm), one L60 40mm Bofors cannon, and one M102 105mm cannon.
And the video. Enjoy!