The Palmaria 155mm self-propelled gun was developed as an in-house venture for interested foreign parties by the Italian concern of OTO Melara. With a long history of defense-minded developments, OTO Melara attempted to address the self-propelled artillery needs of growing or modernizing national armies and promoted their Palmaria as an alternative to more expensive Western and Soviet offerings.
Work on the vehicle began in 1977 of which the chassis was formed from the existing OF-40 Main Battle Tank, allowing both vehicles to share commonality of automotive parts in their design. The OF-40, another export-minded OTO Melara product, was itself developed in 1977 and would enter production in 1980, seeing service with the United Arab Emirates (however less than 50 would be were produced in all). It was hoped that the Palmaria would see better success than the OF-40 and a pilot vehicle was made ready for 1981.
While the OF-40 chassis was kept largely intact, a large boxy, angled turret superstructure was added that housed the 155mm main gun. The howitzer was afforded a heavy duty recoil mechanism and capped by a large double-baffle muzzle brake (a fume extractor is also identified along the middle portion of the barrel). The turret was set to the middle of the hull roof for proper balancing and defense was through a single 7.62mm machine gun mounted on the turret roof, to be used against enemy infantry or low-flying threats. The powerpack was set to the rear of the hull and incorporated an 8-cylinder diesel-fueled engine of 740 horsepower output. The vehicle was suspended atop a torsion bar arrangement and the track system made use of seven road wheels, a rear mounted drive sprocket and a front mounted track idler. Point defense for the running gear was provided through optional side skirt armor. Top road speed was 37 miles per hour with an operational range of 250 miles. The vehicle was crewed by five personnel with the driver in the front right hull and the remaining crew - commander, gunner and two loaders (further assisted by an automatic loader) - in the turret. 30 x 155mm projectiles were stowed aboard as were 1,000 x 7.62mm ammunition.
After passing the requisite trials, the vehicle was ordered by Libya (as many as 210 were delivered) to which serial production ensued in 1982. The Palmaria was also ordered by Nigeria (25) while Argentina ordered only the turrets (25) and had them installed on their existing TAM Medium Tank chassis (as the TAM VCA Palmaria) into 1987. By numbers alone, the Palmaria had already proven a better financial success than the OF-40 MBT.
In practice, the Palmaria was on par with Western offerings. The 155mm main gun could fire a plethora of cleared ammunition options including HE (High-Explosive,) Shrapnel, smoke and illumination rounds at distance (out to 24.7 kilometers, rocket-assisted out to 30 kilometers). The turret offered full 360-degree traversal and elevation of -5 to +70 degrees. An auxiliary power unit allowed for operation of critical systems without having to keep the engine running. The automatic loader provided for one 155mm projectile to be fired every 15 seconds, allowing for sustained rates.
Libyan Army Palmarias were used in anger during the 2011 revolution, several being destroyed by the air campaign sponsored by the United Nations.
The Palmaria receives its name from the island of Palmaria found in the Ligurian Sea near the Gulf of La Spezia. OTO Melara operates a location at La Spezia, Italy.