When Allied weapons engineers got a hold of the MG42 German machine gun, it was pulled apart and examined as inspiration for the next generation of United States small arms. While the MG42 lives on in several design, the American variation of it, the M60 was a long lasting, yet unpopular belt-fed machine gun.
Sometimes, in a bid to make a weapon different than the one it was reversed engineered from, the new device is more complicated and less effective. However, in the case of a submunition deployed by the United States during the 1950s, the M83 Butterfly bomb was an identical copy of the effective Nazi-era original, the SD2 Splitter Bombe.
Created to deny areas and harass enemy forces, the SD2 was devised to linger on the battlefield, creating hazards for emergency workers. It could also be scattered about fields or battlefronts, killing randomly and instilling fear.
Released either from a larger bomb or suspended individually from an aircraft, the SD2 resembled short coffee cans. When released, internal bomblet springs would flip open winglets which then caused drag and a screw-like arming spindle to unwind. Once the small charge was fully suspended at the end of the spindle, beneath the winglets, it was fully armed.
Fused in three different ways the SD2 could detonate in airburst, impact or anti-handling modes. The Germans commenced using the SD2 in raids on Polish forces in 1939, then England, continuing to drop them in the Middle East as well as Soviet Union through t he course of the war.
Used on airfields during Operation Barbarossa (the Nazi invasion of the USSR) and scattered over Allied forces at the Anzio Beachhead, the SD2 was lethal and cursed by the Allies.
As with all submunitions, their size and numbers are what made them particularly effective in area denial. Their deadly bounty and persistence is exemplified by the discovery of an active SD2 in a field on the island of Malta in 2009.
Devious in its simplicity, the United States Army did little to change the established German-era design when it first deployed the M83 in Korea and later in Vietnam.