The M102 is a light, towable 105 mm howitzer used by the United States Army in the Vietnam War, the First Gulf War, and the Iraq War. Overview The M102 105 mm howitzer is used in air mobile (helicopter), attack plane, and light infantry operations. The weapon carriage is lightweight welded aluminum, mounted on a variable recoil mechanism. The weapon is manually loaded and positioned, and can be towed by a 2-ton truck or High Mobility Multipurpose Wheeled Vehicle (HMMWV), can be transported by UH-60 Black Hawk helicopters, or can be dropped by parachute with airborne units. When emplaced, the howitzer's high volume of fire compensates in large measure for the lower explosive weight of the projectile compared to the Army's 155 mm and 8-inch howitzers. Since 1964, the Army acquired 1,150 M102 towed howitzers. The weapon is being replaced by the M119-series 105 mm howitzer. Resistance to change Units were initially equipped with the M101A1 howitzer, virtually the same 105 mm howitzer that had been used to support U.S. forces since World War II. In 1966 a new 105 mm towed howitzer, the M102, was received in Vietnam. The first M102s were issued to the 1st Battalion, 21st Field Artillery, in March 1966. Replacement of the old howitzers continued steadily over the next four years. Many of the more seasoned artillerymen did not want the old cannon replaced. Over the years they had become familiar with its every detail and were confident that it would not disappoint them in the clutch. These experienced artillerymen could offer some seemingly convincing reasons why the M101 was still the superior weapon: its waist-high breech made it easier to load; it had higher ground clearance when in tow; but most important, it was considerably less expensive than the M102. Their arguments, however, were futile. The new M102 was substantially lighter, weighing little more than whereas the M101A1 weighed approximately ; as a result, more ammunition could be carried during heliborne operations, and a 3/4-ton truck rather than a 2½-ton truck was its prime mover for ground operations. Another major advantage of the M102 was that it could be traversed a full 6,400 mils; the M101A1 had a limited on-carriage traverse, which required its trails (stabilizing legs) to be shifted if further traverse was necessary. The M102 fires the same semi-fixed ammunition as the M101, but its longer barrel (32 calibres versus 22 calibres