Getting Closer: Precision Guided Weapons in the Southeast Asia War Despite early developmental problems, precision guided munitions (PGM) revolutionized the air war in Southeast Asia. By the war's end, laser guidance kits turned standard bombs into "smart bombs," making them 100 times more effective than free-fall, unguided bombs. At first, the U.S. Air Force's conventional bombs lacked the accuracy to destroy tough targets like the Thanh Hoa Bridge (or "Dragon's Jaw" Bridge), 70 miles south of Hanoi. In April 1965 radio-guided Martin AGM-12 Bullpup missiles were used on the first attack on the bridge. With just a 250-pound warhead, they proved too lightweight to do any real damage. Repeated air attacks failed to destroy this important bridge completely until very late in the war. The U.S. Air Force tried the electro-optically guided Rockwell International GBU-8 and the Martin Marietta AGM-62 Walleye, but these PGMs had trouble distinguishing the target, were too expensive or still too small for hardened targets like the Dragon's Jaw Bridge. A revolution in PGM development occurred when Col. Joseph Davis Jr., at the Air Proving Ground at Eglin Air Force Base, Fla., and Weldon Word, an engineer with Texas Instruments, adapted the U.S. Army's laser guidance systems to work on bombs. In 1968 the U.S. Air Force evaluated in combat the world's first laser-guided bomb (LGB), the Texas Instruments BOLT-117. Despite its good results, the U.S. Air Force adopted the more powerful Texas Instruments GBU-10 Paveway I, a conventional 2,000-pound MK 84 bomb adapted with a laser guidance system. The resulting accuracy was impressive with almost half of all LGBs dropped in Southeast Asia hitting their target. Most of the other LGBs hit within 25 feet. In April 1972 the U.S. Air Force used LGBs to destroy the Dragon's Jaw Bridge and the more famous Paul Doumer Bridge just outside of Hanoi. During the last year of the war, LGBs destroyed 100 more bridges across North Vietnam. Click on the following links to learn more about precision guided weapons during the Southeast Asia War. Martin AGM-12B Bullpup A Martin Marietta AGM-12C Bullpup B Rockwell International GBU-8 Electro-Optical Guided Bomb Martin Marietta AGM-62 Walleye I Texas Instruments BOLT-117 Laser-Guided Bomb Click here to return to the North Vietnam: Linebacker and Linebacker II Overview.