Italy built six Boeing-designed, Sparviero-class ships based on Tucumcari, and the Patrol Hydrofoil Missileship (PHM) program was formed. The armed hydrofoil was developed under a joint NATO program with the United States, Germany and Italy. The first PHM (Boeing Model 928) was the USS Pegasus (PHM-1) launched in November 1974. It was the first Boeing built craft, and first hydrofoil, to be a listed as a United States Ship (USS).

Armed with a 76 mm rapid-fire cannon and eight AGM-84 Harpoon antiship missiles, the PHM could challenge much larger warships Because it could be self-sufficient for more than five days at a time and be refueled while under way, the PHM could serve as an escort for convoys or travel as part of an aircraft carrier’s battle group, but its main mission was interdicting smugglers and drug traffickers while based in Key West, Fla. In 1993, the PHMs were decommissioned due to government cutbacks.