Coastal vessel, American-built Thai corvette, modernized with a 76mm OTO-Melara, an L/70 Bofors, and other autocannons.
As part of the American Military Assistance Program, two patrol frigates were built in the 1970s for the Thai Navy. These ships were largely identical to the Bayandor-class patrol frigates built for Iran a few years prior, mainly differing with an added set of ASW torpedo tubes, and had the preliminary designations of PF 107 and PF 108. Both ships were modernized in the early 1980s, with a 76mm OTO-Melara and L/70 Bofors replacing the DP 3-inch guns, 2 Oerlikons in a new mount replacing the twin Bofors, and the old radar and sonar replaced with modern Dutch models. Both ships remain in service with the Thai Navy.
HTMS Tapi was built at the American Shipbuilding Company in Toledo, Ohio (What the heck is Toledo), and delivered to the Thai Navy in 1971. It was modernized twice in the 1980s, with the second modernization upgrading some communication systems. It is currently used for patrolling the Thai EEZ, and has participated in exercises with foreign navies. The ship is still in service today.
1x1 76mm OTO-Melara Compact
1x1 40mm Bofors L/70
2x1 20mm Oerlikon GAM-BO1
2x1 12.7mm Pk.93
2x3 324mm Mk.32 TT (Mk.46 torpedoes)
899 tons standard
1191 tons full
Propulsion: 2 Fairbanks-Morse 38TD8-1/8-9 diesel engines, 5250 hp, driving 2 shafts
Speed: 20 knots (37 km/h)
Range: 2400 nmi (at 18 knots)
Signaal WM22-61 FCR
Signaal LW04 search radar
Raytheon SPS-53E navigation radar
Atlas Elektronik DSQS-21C sonar
Gardiner, R., Chumbley, S., & Budzbon, P. (1995). Thailand. In Conway’s All the World’s Fighting Ships 1947-1995 (p. 462). Naval Institute Press.
Saunders, S., & Philpott, T. (2015). Thailand. In Jane’s Fighting Ships 2015-2016 (p. 831). IHS.
Sayers, K. (2021). U.S. Navy Patrol Vessels (pp. 440, 467). McFarland.