a derivative of the "Alabama jackhammer"; a standing "69" in which the woman is upside-down performing fellatio. Once the man senses the nearing of the orgasm he performs an Alabama jackhammer like maneuver in which he belly-flops (still in the 69 position) onto the bed/floor/table, etc., and slams his penis into the back of the woman's throat releasing a heap of semen into the bronchial tubes or esophagus of the woman
"The other day I was 69in'... but standin' up...and when I thought I was gonna cum I pulled a Birmingham belly-flop on my lady and she went "GAH!" and I went "nnnguuuuuuuuuh!!!"
by Dirty Cral Sully October 9, 2008