Skip bombing

Skip bombing was a low-level bombing technique independently developed by several of the combatant nations in World War II, notably Britain, Australia and the United States. After Pearl Harbor (December 1941), it was used prominently against Imperial Japanese Navy warships and transports by Major William Benn of the 63rd Squadron, 43rd Bomb Group (Heavy), Fifth Air Force, United States Army Air Forces in the Southwest Pacific area theater during World War II. General George Kenney has been credited with being the first to use skip bombing with the U.S. Army Air Forces.

The bombing aircraft flew at very low altitudes (200–250 ft (61–76 m)) at speeds from 200–250 mph (320–400 km/h; 170–220 kn). They would release a "stick" of two to four bombs, usually 500 lb (230 kg) or 1,000 lb (450 kg) bombs preferably equipped with four- to five-second time delay fuzes. The bombs would "skip" over the surface of the water in a manner similar to stone skipping and either bounce into the side of the ship and detonate, submerge and explode next to the ship, or bounce over the target and miss. Unlike "Upkeep" or "Highball", this technique used standard bomb types, although only bombs with a generally hemispherical nose — as all regular American World War II "general purpose" aircraft bomb ordnance items were designed to have — would bounce off the water surface properly.

A similar technique was mast-height bombing, in which bombers would approach the target at low altitude, 200 to 500 feet (61 to 152 m), at about 265 to 275 miles per hour (426 to 443 km/h), and then drop down to mast height, 10 to 15 feet (3.0 to 4.6 m) at about 600 yards (550 m) from the target. They would release their bombs at around 300 yards (270 m), aiming directly at the side of the ship. In practice, the techniques were often combined: a bomber would drop two bombs, skipping the first and launching the second at mast height.The Battle of the Bismarck Sea would demonstrate the effectiveness of these low-level attacks on ships. Practice missions were carried out against the SS Pruth, a liner that had run aground in 1923.

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