The M102 is a light, towable 105 mm howitzer used by the United States Army in the Vietnam War, the 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 203 mm 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.

A roller tire attached to the trail assembly of the M102 permits the weapon to be rotated 6,400 mils (360 degrees) around a firing platform, which provides the pivot for the weapon. It can be elevated from −89 mils (−5 degrees) to a maximum of 1,333 mils (75 degrees). The panoramic telescope has a four power, fixed focus optical system, with 178 mils (10 degrees) field of view. It contains dry nitrogen gas to retard fogging and condensation. The parallax shield used during boresighting protects the lens.

Current usage

thumb|left|102 Howitzer belonging to Battery A, 1st Battalion, 206th Field Artillery, 39th Brigade Combat Team, in position at Camp Taji, Iraq 29 May 2004

While the M102 is no longer in active use by the United States Army, having been replaced by the M119, it is still in use by the National Guard. The M102 was last deployed to combat in 2004 by the 1st Battalion, 206th Field Artillery, Arkansas Army National Guard. Seventeen M102 howitzers were deployed to Camp Taji, Iraq. The 1-206th FA provided fire and conducted counter-fire missions in support of 39th BCT operations, an element of the 1st Cavalry Division. The 1-206th scavenged spare parts from nine M102 howitzers that were located in the Camp Taji Boneyard. These howitzers were allegedly captured by the Iraqi Army during the Iran–Iraq War in the 1980s.

The M102 is also used on the United States Air Force's Lockheed AC-130 gunship. The M102 105 mm cannon was modified to be fired from the left rear side door of the AC-130. To accommodate the cannon, the rear side-firing 40 mm guns were replaced by the radome that formerly had been installed in the door cavity. That change provided enough space for the 105 mm gun to be mounted in the doorway in place of the radome. The gun was first used in the later stages of the Vietnam War. The latest AC-130J Ghostrider gunship was not originally planned to include the 105 mm, but designed with enough spare power and room to mount it at some later point. The Air Force decided to include it in January 2015, starting installation on the third aircraft, then having the first two be retrofitted when guns become available; M102s will be pulled off retiring AC-130Us and put into the AC-130Js.

The M102 is used in extremely limited roles by the United States Marine Corps, primarily for firing salutes.

The Malaysian Army used the M102 during Malaysia's second communist insurgency (1968–1988) to bombard insurgent positions on the Malaysia-Thailand border. The guns were transported by helicopter to remote firing positions. All Malaysian M102s have now been decommissioned and are only used for firing salute.

Characteristics

thumb|right|Data plate on an M102 Howitzer

  • Caliber: 105 mm (4.13 in)
  • Length: 21.8 feet (6.4 m)
  • Barrel Length: 32 calibres
  • 50
  • 84 – Used by the Peshmerga
  • 18
  • 40
  • 36
  • 24
  • 140
  • 12
  • – Used on the AC-130J gunships
  • 15
  • – Captured during the Vietnam War

Former operators

  • – Unknown number used by the Republic of Vietnam Airborne Division

See also

  • M101 howitzer – previous American 105 mm towed howitzer
  • M119 howitzer – current towed 105 mm howitzer in US Army service
  • List of artillery
  • List of crew served weapons of the US Armed Forces

References

Works cited

  • The Army Fact File