M109 howitzer

Infobox Weapon
name=M109 Howitzer


caption=M109 self-propelled howitzer of the Royal Netherlands Army
origin=USA
type=Self-propelled artillery
is_vehicle=yes
is_ranged=yes
is_artillery=yes
length=30 ft (9.1 m)
width=10.3 ft (3.1 m)
height=10.7 ft (3.3 m)
weight=27.5 tons
cartridge=separate loading, bagged charge
caliber=155 mm
barrels=
action=
rate= 4 round/min maximum, 1 round/min sustained
velocity=
range= 18,000 m - 30,000 m (with rocket-assisted projectile)
max_range=
feed=
sights=
breech=interrupted screw
recoil=
carriage=
elevation=
traverse=360°
suspension=torsion-bar
speed=35 mph (56 km/h)
vehicle_range=216 mi (350 km)
primary_armament=M126 155 mm Howitzer
secondary_armament=.50 caliber (12.7 mm) M2 machine gun
armour=
engine=diesel
crew=8 (Gun Commander, Driver, 6 x Gunners)
engine_power=
pw_ratio=The M109 is an American-made self-propelled 155 mm howitzer, first introduced in the early 1960s. It has been continually upgraded and improved to today's current version, the M109A6 Paladin, currently only used by the United States Army. The U.S. still maintains a number of M109A5s in its forces. The M109 family is the most prevalent Western indirect-fire support weapon of maneuver brigades of armored and mechanized infantry divisions.

The British Army has replaced its M109s with the AS-90. Several European armed forces have or are currently replacing older M109s with the German PzH2000, which significantly outperforms the M109 in many aspects. Significant upgrades to the M109 have been introduced by the U.S. (see variants below) and in Switzerland (KAWEST). With the cancellation of the Crusader program in the U.S., the Paladin will remain the principal self-propelled howitzer for the U.S. military a few more years, until the NLOS-C from the U.S. Army's Future Combat Systems program comes online in 2008-2010.

The crew of the M109 consists of a section chief, driver, three gunners who prepare the ammunition, load, and fire the weapon, and two gunners who aim the cannon. The gunner aims the cannon left or right (deflection), the assistant gunner aims the cannon up and down (quadrant). The M109A6 Paladin needs only one gunner and two ammunition handlers for a total crew of six.

History

The M109 was the medium variant of a U.S. program to adopt a common chassis for its self-propelled artillery units. The light version, the M108 Howitzer, was phased out during the Vietnam War,and many were rebuilt as M109s.

The M109 saw its combat debut in Vietnam. Israel used the M109 against Egypt in the 1973 Yom Kippur War and in the 1982 Lebanon War and 2006 Lebanon War. Iran used the M109 in the Iran–Iraq War, in the 1980s. The M109 saw service with the British Army, the Egyptian Army and Saudi Arabian Army in the 1991 Gulf War. The M109 also saw service with the U.S. Army in the Gulf War, as well as in the Iraq War from 2003 to present.

Upgrades to the cannon, ammunition, fire control, survivability, and other electronics systems over the design's lifespan have vastly expanded the system's capabilities (see variants). Some of these capabilities include tactical nuclear projectiles, cannon launched guided projectiles (CLGP or Copperhead), Rocket Assisted Projectile (RAP), scatterable mines (FASCAM), and improved conventional munitions (the Dual-Purpose Improved Conventional Munition, DPICM).

Armament

* Primary: M126 155 mm Howitzer (M109), M126A1 155 mm Howitzer (A1), M185 155 mm Howitzer (A2/A3/A4), M284 155 mm Howitzer (A5/A6)
* Secondary: .50 caliber (12.7 mm) M2 machine gun, Mk 19 Mod 3 40 mm Automatic Grenade Launcher, or 7.62 mm M60 or M240 machine gun

Variants

M109

First produced in 1963, with 155 mm M126/A1 gun in the M127 Howitzer Mount, 28 rounds of 155 mm were carried. Also armed with a .50cal M2HB machine gun mounted, and 500 rounds of .50cal ammunition.

M109A1/A1B

Replaced M126 with longer barreled M126A1 gun for greater effective range. Same M127 mount and ammunition amounts carried. A more recent model, intended for export incorporated more recent improvements into a new production M109A1. These vehicles were designated M109A1B.

M109A2

Incorporated 27 Reliability, Availability, and Maintainability (RAM) mid-life improvements. Most notably, the long barreled 155 mm M185 cannon in the M178 gun mount, ballistic protection for the panoramic telescope, counterbalanced travel lock, and the ability to mount the M140 alignment device. Stowage increased from 28 rounds of 155 mm, to 36 rounds, .50cal ammunition amount remain 500 rounds.

M109A3/A3B

M109A1s and M109A1Bs rebuilt to M109A2 standard respectively. Some A3s feature three contact arm assemblies while all A2s have five.

M109A4

M109A2s and M109A3s improved with Nuclear, Biological, and Chemical / Reliability, Availability, and Maintainability (NBC/RAM) improvements, including air purifiers, heaters, and Mission Oriented Protective Posture (MOPP) gear.

The traversing mechanism's clutch is now hydraulic, as compared to the electric mechanism on previous M109s, and features a manual override in the event of an electrical failure. The A4 also adds an additional hydraulic filter, for a total of two. Also included, is an improvement to the engine starting equipment, greatly improving the ability to start in an emergency.

Ammunition amounts remain the same as two previous models.

M109A5

Replaces M185 cannon in M178 mount with 155 mm M284 cannon in the M182 mount, giving the A5 even greater range than before.

M109A5+

Various manufacturers have upgraded the fire control and other components of the M109A5.

M109A6 "Paladin"

Overall product improvement in the areas of Survivability, RAM, and armament. This includes increased armor, redesigned (safer) internal stowage arrangement for ammunition and equipment, engine and suspension upgrades, and product improvement of the M284 cannon and M182A1 mount. The greatest difference is the integration of an inertial navigation system, sensors detecting the weapons' lay, automation, and an encrypted digital communication system which utilizes computer controlled frequency hopping to avoid enemy electronic warfare and allow the howitzer to send grid location and altitude to the battery fire direction center (FDC). The battery FDCs in turn coordinate fires through a battalion or higher FDC. This allows the Paladin to halt from the move and fire within 30 seconds with accuracy equivalent to the previous models when properly emplaced, laid, and safed--A process that required several minutes under the best of circumstances. Tactically, this improves the systems survivability by allowing the Battery to operate dispersed by pairs across the countryside and allowing the howitzer to quickly displace between salvos, or if attacked by indirect fire, aircraft, or ground forces.

On an operational level this weapon represents a dramatic improvement in the performance of field artillery. This improvement in performance is perhaps as great as that of the first self propelled artillery over the preceding towed artillery. This is because the howitzers no longer need to occupy fixed firing positions but may now move with the advancing combat forces. They need stop only when a target is identified. After firing on a target, the Paladin is immediately able to resume movement.

Ammunition stowage is increased from 36 rounds of 155 mm, to 39 rounds, .50cal ammunition amounts remain the same.

The M109A6-PIM is the latest upgrade and is fitted with some components of the canceled Crusader. These include an autoloader, a modern electric gun drive to replace the hydraulically operated elevation and azimuth drives designed in the early 1960s, and updated fire control systems. Other major upgrades include a new chassis based on the Bradley infantry fighting vehicle.
* [http://www.fas.org/man/dod-101/sys/land/m109a6.htm M109A6 Paladin]
* [http://www.globalsecurity.org/military/library/news/2007/10/mil-071008-bae-systems03.htm M109A6 PIM]
* [http://www.armyrecognition.com/Amerique_du_nord/Etats_Unis/vehicule_artillerie/M_109/M109A6_Paladin_PIM_Partnership/LAND_M106A6-PIM_self-propelled_howitzer_001.jpgM109A6 PIM photo]

M109 "KAWEST"

This Swiss improved version produced by Ruag incorporates a new Swiss-designed L47 155 mm Gun with an increased firing range of up to 36 km. The L47 155 mm Gun is derived from the Swiss Bison fortress gun's inertial navigation system coupled with a new gun-laying system and more ammunition storage. The KAWEST requires only 6 crew members instead of 8, and is able to fire 3-round bursts within 15 seconds or maintain a constant firing rate of over one round per minute.Technical modifications:Increased firing range of up to 27 km, increased rate of fire (burst of 3 rounds in 15 sec.), increased ammunition autonomy ( 40 rounds, 64 charges).New electrical system increases reliability (better than Mil STD 1245A, higher operational readiness, increased mean time between failures, fault-finding diagnostics with test equipment.)Integrated inertial navigation and positioning system, increased mobility (gears, engine), day and night operations capabilities, effective fire suppression system installed, NEMP and EMP protection. Camouflage: paint and netting.Upgraded Swiss PzHb (Panzerhaubitze) 79 and 88 (M109A1) are known as respectively PzHb 79/95 and PzHb 88/95.

M992

The Field Artillery Ammunition Supply Vehicle (FAASV) is built on the chassis of the M109-series. It replaces the M548 supply vehicle. Unlike the M548 it is armored. This ammunition vehicle has no turret and a taller superstructure to store 93 rounds and an equivalent number of powders and primers. There is a maximum of 90 conventional rounds, 45 each in two racks, and 3 M712 Copperhead rounds. Much of the remaining internal crew space is taken up by a hydraulically powered conveyor system designed to allow the quick uploading of rounds or transfer of rounds to the M109-series howitzer. Most early models had an additional mechanism called an X-Y Conveyor to lift the rounds into the honeycomb-like storage racks in the front of the superstructure. A ceiling plate above the two racks can be unbolted and opened to allow the racks to be winched out of the vehicle. This vehicle is fitted with a Halon fire suppression system and a weapons mount similar to that on the M109 turret, usually mounting a Mk 19 40 mm grenade machinegun for local defense against infantry and light armored vehicles. The latest models have a mounting point for two secure radios.

The vehicle also contains a 2-stroke diesel powered auxiliary power unit (APU) that can power all non-automotive energy requirements on the FAASV and on the howitzer when a slave cable is used to connect the two. This reduces fuel consumption when mobility is not required.

Training Systems

The US Army uses the Fire Support Combined Arms Tactical Trainer (FSCATT) in two versions for initial and sustainment training of the M109A6 and M109A5. The system uses an actual surplus turret and a simulated ammunition system.

The Swiss Army uses a highly advanced KAWEST trainer from Van Halteren Metaal of the Netherlands.

The Dutch, Belgian, Thai, and Israeli Armies have various configurations of the Van Halteren Metaal LARIT M109 trainer.

Operators

M109A1

*DEN - 76 (upgraded to A3DK)
*ETH - 17
*GRE - 33 A1/A1B
*KUW - 5 A1B
*LBY - 18 A0
*OMA - 15 A0
*PER - 12
*SAU - 28
*TUN - 11
*IRN - 390

M109A2/A3

*BEL - 127 A2 (of which 64 upgraded to A4BE; all now decommissioned) and 40 A3 (sold to Brazil)
*GER - 570 A3GE A1/A2 (phased out by 1 July 2007, largely replaced by the PzH 2000, last service with Mountain Artillery Battalion 225)
*GRE - 132 A2
*EGY - 279 A2
*KOR - 1,040 (K55)
*MAR - 84
*NOR - 126 A3NG
*PAK - 150 A2
*POR - 6 A2
*THA - 20
*NLD - 126 A2/90 phased out, largely replaced by the PzH 2000. [Being phased out in 2007-2008 in favor of the PzH 2000 NL: cite web|url=http://www.landmacht.nl/materieel/huidig_materieel/Gevechtssteunmaterieel/m109.aspx|title=Koninklijke Landmacht - "M109" (combat support material)|language=Dutch|accessdate=2006-08-24]
*BRA - 40 A3 (former Belgian)
*ROC(Taiwan) - 225

M109A4

*BEL - 64 A4BE (decommissioned)
*CAN - 76 A4+ (decommissioned)

M109A5

*GRE - 12
*EGY - 201
*ISR - 600 "Doher"
*POR - 18
*ESP - 96
*THA - 20
*MAR - 60
*SAU - 48
*flag|Bahrain - 20

M109A5+

*AUT

M109A6 Paladin

*USA - 950

M109 KAWEST

*SUI
*CHI - 24 (former Swiss, upgraded by RUAG.)

Footnotes

See also

*M107 (projectile)
*List of artillery
*List of crew-served weapons of the U.S. Armed Forces

External links

* [http://www.qrsdc.com M109A6/M992A2 Sample Data Collection]
* [http://www.inetres.com/gp/military/cv/arty/M109.html Gary's Combat Vehicle Reference Guide]
* [http://www.fas.org/man/dod-101/sys/land/m109.htm Fas.org]
* [http://www.globalsecurity.org/military/systems/ground/m109-intro.htm Globalsecurity.org]
* [http://www.israeli-weapons.com/weapons/vehicles/self_propelled_artillery/m109/M109.html Israeli-weapons.com]
* [http://www.ruag.com/ruag/juice?pageID=84521 ruag.com]
* [http://prozny.com/_photo/_m109/8.jpgPhotos of M109 shooting] .
* [http://www.danskpanser.dk/Baeltekoretojer/M109A3.htm Danish M109 A3]