In 2001-2002, with foreign wars looming for the NATO nations, the subject of a potential shortfall of naval gunfire support was not only a hot topic in the United States. NATO member Germany, also possessing a navy and also deploying troops to foreign shores, was concerned about the problem.
At the time, Germany was in the process of building out a new class of frigate. As a demonstration, several German concerns (HDW, Rheinmetall and others) embarked on the MONARC project. MONARC is an acronym for MOdular Naval ARtillery Concept. In brief, MONARC set out to prove that in order to gain firepower you could mount a 155mm howitzer aboard a naval vessel, firing NATO-standard 155mm ammunition. Not only that, you could do so relatively easily and cheaply by avoiding the whole process of designing a new gun turret to house the howitzer, and instead transplanting the already-fielded turret from a PzH 2000 self-propelled artillery vehicle, gun and all, onto the ship.
Several factors made this an attractive prospect. For one, the turret was roughly the same size as the turrets already designed for the frigate in question, the F124 class Hamburg, which was under construction. For another, the PzH turret was completely self-contained, requiring only 24-volt power to operate, which the ship could of course easily supply. Finally, of course, since the German army had procured around 185 of these vehicles, the turrets were a known quantity.
There were difficulties to be overcome. The most critical was that the larger gun (the Hamburg was designed to take a 76mm naval mount) would have a larger recoil. In order to protect the structure of the ship, the turret had to be isolated from the ship by an elastic buffering system. In addition, the PzH did not boast a stabilization system for the gun, since the artillery vehicle was intended to stop before firing. To cope with normal motion of the ship at sea, however, a stabilized gun was needed.
These turned out not to be insurmountable. After modifications to the gun and test firings on land, the MONARC turret was indeed placed aboard Hamburg, and turned out to be operable. There is a Rheinmetall picture of the turret installed on the ship. Note that the MONARC retains the land camouflage pattern of its army origins. Spacing between the turret and the ship is also visible at the base, indicating that it is mounted on the recoil buffers.
Despite its successful installation and testing, the MONARC was not approved for purchase by the German Navy or any other customer. The turret was removed, and Hamburg was delivered with a standard OTO Melara Compact 76mm gun turret. Although no official reason for dropping the project was given, an article in the April 2007 issue of Marine Forum magazine explains that in addition to increased expenses for ammunition systems modification belowdecks, the cost and complexity of navalizing the complete set of systems inside the PzH turret ended up being prohibitive.
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Iron Noder 2010