Editing M102 howitzer (section)

== Overview ==
The M102 105&thinsp;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 203 mm howitzers. Since 1964, the Army acquired 1,150 M102 towed howitzers. The weapon is being replaced by the [[M119 howitzer|M119]]-series 105&thinsp;mm howitzer.<ref name="globalsecurity.org">[http://www.globalsecurity.org/military/systems/ground/m102.htm Global Security. Org, M102 105&thinsp;mm Lightweight Towed Howitzer]</ref>

=== Resistance to change ===
Units were initially equipped with the [[M101 howitzer|M101A1 howitzer]], virtually the same 105&thinsp;mm howitzer that had been used to support U.S. forces since [[World War II]]. In 1966 a new 105&thinsp;mm towed howitzer, the M102, was received in Vietnam. The first M102s were issued to the 1st Battalion, [[21st Field Artillery Regiment (United States)|21st Field Artillery]], in March 1966.<ref name="globalsecurity.org" /> 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.<ref name="globalsecurity.org" /> Their arguments, however, were futile.

The new M102 was substantially lighter, weighing little more than {{convert|1.5|ST}} whereas the M101A1 weighed approximately {{convert|2.5|ST}};<ref name="globalsecurity.org" /> as a result, more ammunition could be carried during heliborne operations, and a 3/4-ton truck rather than a [[M35 2½-ton cargo truck|2½-ton truck]] was its prime mover for ground operations. Another major advantage of the M102 was that it could be traversed a full 360°; 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 [[Shell (projectile)#Separate loading cased charge|semi-fixed]] ammunition as the M101, but its longer barrel (32 calibres versus 22 calibres on M101) allows a slightly higher muzzle velocity and thus enhanced firing range.<ref name="Christopher Chant"/> A low silhouette made the new weapon a more difficult target for the enemy, an advantage that far outweighed the disadvantage of being somewhat less convenient to load.