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date of publication: 20-07-2013

Self-propelled mortar, 50 caliber machine gun


Armored Infantry Vehicle M59

These were DRIVE, HILLY, and reverse (REV). The transmission shifted automatically to the appropriate speed in each range. Early vehicles also had a neutral position for only the transmission in each differential range. The left and right auxiliary shifting levers were used to engage the transmission without engaging the controlled differential.

This permitted the drive shafts to rotate without moving the vehicle, providing power for the ramp hydraulic system. The could be operated on one engine in the low differential range. The drive shaft to the dead engine was removed to avoid damage to the Hydramatic transmission. However, in an extreme emergency, the vehicle could be operated by removing the cross shaft locking pin and lowering the auxiliary shifting lever to the disengaged position.

Armored Infantry Vehicle M59

The ignition for the dead engine should be turned off in all cases and the fuel shut-off valves should be closed on vehicles F7 - F786. Later vehicles did not have fuel shut-off valves. The commander's platform was adjustable in height and was attached, along with a folding seat, to the seat post under the commander's cupola on vehicles F7 -F2941.

On F7 - F1312, the cupola was the same as on the pilots with six vision blocks and an external rotating mount for a 50 caliber machine gun. On F1313 - F2941, a new cupola was installed with four M17 periscopes replacing the vision blocks. This cupola also carried a 50 caliber machine gun on an external mount with 360 degree rotation.

The cupola commander's M13

Beginning with vehicle F2942, the M13 cupola was provided for the vehicle commander. This cupola was armed with an internally mounted, turret type. 50 caliber machine gun. The weapon was elevated and the cupola rotated manually. The ammunition system consisted of a 735 round ammunition box with the commander's seat attached.

It was installed on a slip ring on the hull floor and connected to the cupola through a torque mount so that it could rotate with the cupola. An electric system fired the machine gun and powered the ammunition booster. The cupola contained four vision blocks with two in the body and two in the door. An M28 periscope sight in the cupola roof was used to aim the 50 caliber machine gun.

M59 is swimming

The was used for a number of experimental installations. The French SS-10 and SS-11 antitank missile systems were mounted on the vehicle for evaluation. A remote controlled 50 caliber machine gun also was installed experimentally over the commander's station on another M59. Other test programs included a flat track suspension eliminating the track support rollers.

The requirement still existed for a full tracked mortar carrier. In March 1953, a project was initiated to comert the armored infantry vehicle T59 () into carriers for the 81mm, 105mm, and 4.2 inch mortars. These vehicles were designated as the T82, T83, and T84 respectively.

The M59 is armed with SS-10 missiles

The initial effort was concentrated on the T84 and it was completed before work began on the T82 and T83. By this time, the requirement for the 105mm mortar had been dropped and the T83 project was terminated. Work continued on the 81mm self-propelled mortar T82, but it also was canceled in favor of a self-propelled mortar based upon the new Ml 13 .

The 4.2 inch self-propelled mortar T84 consisted of the 4.2 inch M30 mortar installed on a modified M59. The roof hatches on the personnel compartment were redesigned to include a front hatch, a center hatch, and a rear hatch. The front hatch was bolted to the hull and connected to the center hatch by a torsion hinge. The center and rear hatches also were hinged together and they could be folded up on top of the front hatch providing an open area for the mortar.()

The M59 is armed with SS-11 missiles

Hatch doors were located in the front and rear roof hatches. The escape door in the rear ramp was shifted to the right as viewed from the outside. This provided stowage space on the left rear for the base plate and rotator assembly from the M24A1 ground mount for the 4.2 inch mortar. OCM 36027, dated 25 November 1955, standardized the new vehicle as the 4.2 inch, full-tracked, self-propelled mortar M84.

Self-propelled mortar M84 Self-propelled mortar M84
Self-propelled mortar M84 Self-propelled mortar M84
Self-propelled mortar M84