The World's Worst Weapons ! Not every weapon design can look forward to decades of service and popularity like the famous Ma Deuce, the AK, the MiG-21 or Mirage. There's always the ugly ducklings in every family of design. 45/5 mod. 35 light mortar (Italy) The modello 35 was needlessly complicated, expensive to manufacture, and fired tiny shells with poor explosive effect. Obviously the Italians were looking for a high rate of fire, but it's hard to understand why they didn't focus on a simpler weapon. Mistel (Germany) A waste of fighters and bomber aircraft, vulnerable and apparently never managed to inflict any significant damage on Allied targets. Aphrodite drones (USA) War-weary B-17s packed with explosives and remote-controlled to hit German targets. All of the missions were dismal failures: the only one to hit its target failed to explode and the Germans got their hands on a nearly-intact B-17 with RC equipment. Blackburn Roc (UK) Even worse than the Defiant turret fighter, it was slow, vulnerable and useless as a fighter (at least the Defiant gave valiant service as a night fighter). Relegated to non-combat duties and ended up getting its only confirmed kill by shooting down a German bomber while parked on an airfield. Breda Ba.88 (Italy) Hated by the poor Regia pilots who had to fly it, the Ba.88 could hardly get off the ground with a full bomb load, was extremely overweight, slower than most biplane fighters, and very vulnerable. Most ended up as airfield decoys. Chauchat machine gun (France) Awkwardly designed, terribly built, unreliable and given to failure in combat. Considered the worst machine gun of WWI and a stark contrast to the excellent Hotchkiss series of weapons that served alongside it. Of the top of my head I can recall a few other examples, like the Japanese WW2 service pistol which was a real pos, the XP-79 flying wing, etc. Any others out there that really stood out for their sheer level of fail?