The self-propelled howitzer M110 was introduced to service in 1963. It was then the heaviest self-propelled artillery piece in US Army. It replaced in service other 203 mm howitzers, such as M43 and M55. The roots of the 203 mm cannon itself go back to the British 8 inch (exactly 203,2 mm) howitzer of World War I, which was later used and copied by Americans. During World War II it was used as a towed weapon.
In 1956 US Army began evaluation of a new design, which was required to to be air transportable. Pacific Car&Foundry presented several prototypes of self-propelled guns: 155 mm, 175 mm and 203 mm howitzer. In course of trials it was decided to standarize the 175 mm SP Gun as M107, the 203 mm SP howitzer as M110 and also the M578 armoured recovery vehicle - all sharing common chassis and many parts.
M110 is usually used by the divisional artillery. Every vehicle operates together with an ammo carrier, the M548 is commonly employed in this role. The crew of such team consists of 13 people, among them 2 drivers. Five people are carried on the howitzer itself, together with two rounds of ammo ready to use, the remainder of crew and ammo is carried on the M548.
M110 is equipped with a hydraulic-operated spade that secures the howitzer to the ground to take the gun recoil energy. The hydraulic systems of the M110 are quite extensive, used not only for traversing and elevating the gun and deploying and retracting the spade, but also for power loading and ramming the projectile.
In Vietnam the M110 howitzers enjoyed a good reputation for pin-point accuracy and heavy punch. Of great value was the option of quickly switching the gun tubes from 203 mm howitzer to 175 mm gun and vice versa, depending on current needs (accuracy and firepower versus long range).
|Length (without gun):||6459 mm|
|Length (over gun):||7479 mm|
|Service weight:||26 500 kg|
|Main armament:||8'' (203 mm) howitzer M2A2 on a M158 mount|
|Armor hull:||Welded rolled steel plate 12,7 mm|
|Propulsion:||General Motors 8V71T; 8 cylinder, 2 cycle, vee, supercharged diesel|
|Power (gross/net):||302 kW / 257,3 kW @ 2300 rpm|
|Torque:||1328,9 Nm @ 1700 rpm / 1213,6 Nm @ 1600 rpm|
|Fuel capacity:||1100 L|
|Transmission:||Allison XTG-411-2A, 4 ranges forward, 2 reverse|
|Suspension:||torsion bars, hydraulically locked for firing|
|Trench crossing:||2,1 m|
|Vertical obstacle:||1 m|
|Crew:||13 people, 8 of which in auxiliary vehicle (M548)|