M102 howitzer
Encyclopedia
First introduced during the Vietnam War
, the M102 was the light-towed 105 mm howitzer
used by the United States Army
in the Vietnam War
, the First Gulf War
, and most recently in the Iraq War.
-series 105mm 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 by far the better weapon. It weighed little more than 1½ tons whereas the M101A1 weighed approximately 2½ tons; 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. 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.
A roller tire attached to the trail assembly of the M102 permits the weapon to be rotated 6,400 mils around a firing platform, which provides the pivot for the weapon. The weapon 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 field of view. It contains dry nitrogen gas to retard fogging and condensation. The parallax shield used during boresighting protects the lens.
The trails are made of aluminum alloy. They are a single box trail in wishbone shape, and serve three purposes, which are: mobility, stability, and stowage of section equipment. The lunette is the towing pintle that allows the weapon to be connected to the vehicle. When towing, vehicle has a fixed or seized tow pintle; remove the lock plate located under the lunette. The drawbar has two positions. The drawbar is lowered for travel, and raised for firing.
There are two lifting brackets to connect slings to, when the howitzer is being lifted by helicopter. A third bracket is located on front yoke. The carriage handles are used by crew members to lifting and shifting the howitzer during loading, unloading, and emplacing the howitzer.
The firing platform attaches to the howitzer lower carriage by using a socket and a locking handle. The eight holes are for the stakes needed to stake the howitzer in position. Platform stakes are issued in three sizes. There are four 15-inch stakes issued. These are used for frozen or rocky terrain, and are normally issued only where needed, such as extremely cold areas. There are eight 24-inch stakes issued, and they are used for hard packed ground. Four 38-inch stakes are issued to be used for soft ground.
, 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 Bone Yard. Allegedly these howitzers were captured by the Iraqi Army during the Iran-Iraq War in the 1980s.
The M102 is also used on the USAF
's Lockheed AC-130
gunship. The M102 105mm cannon was modified to be fired from the left rear side door of the AC-130 gunship aircraft. To accommodate this cannon, one of the side-firing 40mm guns was removed from the aircraft and replaced by the radome that formerly had been installed in the door cavity. That change provided enough space for the 105mm gun to be mounted in the doorway in place of the radome. The gun was first used extensively beginning with the Vietnam War and is still used to the present day.
The M102 is used in extremely limited roles by the United States Marine Corps
, primarily for firing salutes.
Vietnam War
The Vietnam War was a Cold War-era military conflict that occurred in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. This war followed the First Indochina War and was fought between North Vietnam, supported by its communist allies, and the government of...
, the M102 was the light-towed 105 mm howitzer
Howitzer
A howitzer is a type of artillery piece characterized by a relatively short barrel and the use of comparatively small propellant charges to propel projectiles at relatively high trajectories, with a steep angle of descent...
used by the United States Army
United States Army
The United States Army is the main branch of the United States Armed Forces responsible for land-based military operations. It is the largest and oldest established branch of the U.S. military, and is one of seven U.S. uniformed services...
in the Vietnam War
Vietnam War
The Vietnam War was a Cold War-era military conflict that occurred in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. This war followed the First Indochina War and was fought between North Vietnam, supported by its communist allies, and the government of...
, the First Gulf War
Gulf War
The Persian Gulf War , commonly referred to as simply the Gulf War, was a war waged by a U.N.-authorized coalition force from 34 nations led by the United States, against Iraq in response to Iraq's invasion and annexation of Kuwait.The war is also known under other names, such as the First Gulf...
, and most recently in the Iraq War.
An Air Mobile Howitzer for the Vietnam War
The M102 105mm howitzer is used in air mobile (helicopter) 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 155mm and 8-inch howitzers. Since 1964, the Army has acquired 1,150 M102 towed howitzers. This weapon is being replaced by the M119M119 howitzer
The M119 Howitzer is a lightweight 105-mm howitzer used by the United States Army. It can be easily airlifted, even by helicopter, or dropped by parachute. It does not need a recoil pit.-Development:...
-series 105mm howitzer.
Resistance to Change
Units were initially equipped with the M101A1 howitzerM101 howitzer
The 105 mm M2A1 howitzer was the standard light field howitzer for the United States in World War II, seeing action in both European and Pacific theaters. Entering production in 1941, it quickly entered the war against the Imperial Japanese Army in the Pacific, where it gained a reputation...
, 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
21st Field Artillery Regiment (United States)
The 21st Field Artillery Regiment is an Field Artillery regiment of the United States Army first formed in 1916-Lineage:Constituted 1 July 1916 in the Regular Army as the 21st Field ArtilleryOrganized 1 June 1917 at Camp Wilson, Texas...
, 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 by far the better weapon. It weighed little more than 1½ tons whereas the M101A1 weighed approximately 2½ tons; 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. 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.
Basic Design
The 105-mm howitzer M102 is a lightweight towed weapon, which has a very low silhouette when in the firing position. The M102 howitzer fires a 33-pound projectile of semifixed ammunition and at charge 7 will fire 11,500 meters. It has a muzzle velocity of 494 meters per second. The maximum rate of fire is 10 rounds per minute for the first 3 minutes, with a sustained rate: 3 rounds per minute.A roller tire attached to the trail assembly of the M102 permits the weapon to be rotated 6,400 mils around a firing platform, which provides the pivot for the weapon. The weapon 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 field of view. It contains dry nitrogen gas to retard fogging and condensation. The parallax shield used during boresighting protects the lens.
The trails are made of aluminum alloy. They are a single box trail in wishbone shape, and serve three purposes, which are: mobility, stability, and stowage of section equipment. The lunette is the towing pintle that allows the weapon to be connected to the vehicle. When towing, vehicle has a fixed or seized tow pintle; remove the lock plate located under the lunette. The drawbar has two positions. The drawbar is lowered for travel, and raised for firing.
There are two lifting brackets to connect slings to, when the howitzer is being lifted by helicopter. A third bracket is located on front yoke. The carriage handles are used by crew members to lifting and shifting the howitzer during loading, unloading, and emplacing the howitzer.
The firing platform attaches to the howitzer lower carriage by using a socket and a locking handle. The eight holes are for the stakes needed to stake the howitzer in position. Platform stakes are issued in three sizes. There are four 15-inch stakes issued. These are used for frozen or rocky terrain, and are normally issued only where needed, such as extremely cold areas. There are eight 24-inch stakes issued, and they are used for hard packed ground. Four 38-inch stakes are issued to be used for soft ground.
Current Usage
While the M102 is no longer in use by the Active United States Army, having been replaced by the M119M119 howitzer
The M119 Howitzer is a lightweight 105-mm howitzer used by the United States Army. It can be easily airlifted, even by helicopter, or dropped by parachute. It does not need a recoil pit.-Development:...
, it is still in use by the National Guard
United States National Guard
The National Guard of the United States is a reserve military force composed of state National Guard militia members or units under federally recognized active or inactive armed force service for the United States. Militia members are citizen soldiers, meaning they work part time for the National...
. The M102 was last deployed to combat in 2004 by the 1st Battalion, 206th Field Artillery, Arkansas Army National Guard
Arkansas Army National Guard
The Arkansas Army National Guard is a component of the Arkansas National Guard and the United States National Guard. Nationwide, the Army National Guard comprises approximately one half of the US Army's available combat forces and approximately one third of its support organization...
. Seventeen M102 howitzers were deployed to Camp Taji
Camp Taji
Camp Taji is a military installation, also known as Camp Cooke used by coalition forces near Taji or Al Taji , Iraq. The camp is located in a rural region approximately north of the city of Baghdad in the Baghdad Governorate.-History:...
, 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
1st Cavalry Division
1st Cavalry Division can refer to several cavalry units:* 1st Cavalry Division * 1st Cavalry Division * 1st Cavalry Division * 1st Cavalry Division * 1st Indian Cavalry Division...
. The 1-206th scavenged spare parts from nine M102 howitzers that were located in the Camp Taji Bone Yard. Allegedly these howitzers were captured by the Iraqi Army during the Iran-Iraq War in the 1980s.
The M102 is also used on the USAF
United States Air Force
The United States Air Force is the aerial warfare service branch of the United States Armed Forces and one of the American uniformed services. Initially part of the United States Army, the USAF was formed as a separate branch of the military on September 18, 1947 under the National Security Act of...
's Lockheed AC-130
Lockheed AC-130
The Lockheed AC-130 gunship is a heavily-armed ground-attack aircraft variant of the C-130 Hercules transport plane. The basic airframe is manufactured by Lockheed, while Boeing is responsible for the conversion into a gunship and for aircraft support...
gunship. The M102 105mm cannon was modified to be fired from the left rear side door of the AC-130 gunship aircraft. To accommodate this cannon, one of the side-firing 40mm guns was removed from the aircraft and replaced by the radome that formerly had been installed in the door cavity. That change provided enough space for the 105mm gun to be mounted in the doorway in place of the radome. The gun was first used extensively beginning with the Vietnam War and is still used to the present day.
The M102 is used in extremely limited roles by the United States Marine Corps
United States Marine Corps
The United States Marine Corps is a branch of the United States Armed Forces responsible for providing power projection from the sea, using the mobility of the United States Navy to deliver combined-arms task forces rapidly. It is one of seven uniformed services of the United States...
, primarily for firing salutes.
Characteristics
- Caliber: 105 mm (4.13 in)
- Length: 17.1 feet (5.2 m)
- Width: 6.4 feet (2 m)
- Height: 5.2 feet (1.6 m)
- Weight: 1.5 tons (1.4 t)
- Crew: 8
- Rate of fire: 10 rounds per minute maximum, 3 rounds per minute sustained
- Range: 11,500 m (7.1 miles), 15,100 m (9.4 miles) with rocket-assisted projectile
See also
- M101 howitzerM101 howitzerThe 105 mm M2A1 howitzer was the standard light field howitzer for the United States in World War II, seeing action in both European and Pacific theaters. Entering production in 1941, it quickly entered the war against the Imperial Japanese Army in the Pacific, where it gained a reputation...
- previous American 105mm towed howitzer - M119 howitzerM119 howitzerThe M119 Howitzer is a lightweight 105-mm howitzer used by the United States Army. It can be easily airlifted, even by helicopter, or dropped by parachute. It does not need a recoil pit.-Development:...
- next towed 105mm howitzer in US Army service - List of artillery
- List of crew served weapons of the US Armed Forces