Palmaria was the result of a private development by Oto Melara after the experience gained in the development of new barrels for the M-109 self propelled howitzers in service with the Italian Army. They also produced elements for the FH-70 towed howitzer.The OF-40 tank chassis was chosen to mount the turret, and although with some minor modifications, the internal layout is the same as in the tank. The only difference is that Palmaria houses 5 crew members: commander, pointer, loader assistant, loader and driver.Palmaria‘s hull was made of welded steel plates, and the turret was constructed with an aluminum alloy. The personnel chamber is separated from the engine by an armoured bulkhead, placing the driver in the center of the frontal section of the hull.The 155mm Palmaria‘s howitzer was a development of the same installed by Oto Melara in the Italian M-109. It is a special steel monobloc tube with double outlet muzzle brake and a cylindrical gas extractor in the center of the barrel. The rifled bore has 42 riffling grooves.After each shot the barrel returns to the loading position, which can be done manually or automatically. Only the shell was reloaded automatically, then the propellant charges were introduced manually. The rate of fire was two per minute in manual mode and four per minute in automatic mode.The Palmaria‘s engine is a 8 cylinder Fiat four stroke diesel engine, supercharged by pressured air and cooled by liquid that developes 750 hp at 2,200 rpm. It also has a cooling plant with two hydrodynamic fans to cool the coolant mixture of the engine. The turret houses four crew members and has a goniometer and a telemetric viewfinder for direct aiming. It also has a roof-hatch for the commander, and two side access doors along with a rectangular hatch on the left rear where the ammunition is reloaded.Palmaria howitzer did not get many orders in the market, being only purchased by Nigeria (25), Argentina (25), which only acquired the turrets, and Libya, (160), which was the largest user, but did not fully complete the initial order of 210 vehicles.Libya is the largest user of the Palmaria having had about 160 in service, although currently its number is quite minor and there is evidence that several were destroyed by multinational forces during the Libyan Civil War in 2011.
