Radar cross section (RCS) reduction features have been incorporated into the
Formidable class design, with inclined hull sides and bulwarks as well as concealment of ship boats and replenishment-at-sea equipment behind low-RCS curtains. The
Formidable class have a significantly reduced profile than the
La Fayette class and its other derivatives, due to the smaller superstructure and the use of enclosed sensor mast technology. The frigate is also constructed entirely of steel, unlike the
La Fayette class which makes extensive use of weight-saving composite structures in its aft superstructure block. The frigates also possess better sea keeping qualities and are able to stay at sea for longer periods of time. The radar provides all-round automatic search and tracking of both air and surface targets, and is integrated with the
MBDA Aster air defence system. Utilising the DCNS
Sylver vertical launch system (VLS), each frigate is equipped with 32 cells. It is reported that the frigates have a special
surface-to-air missile configuration, combining the Thales Herakles radar with the Sylver A50 launcher and a mix of Aster 15 and 30 missiles. The
Formidable-class frigates are key nodes within the
Singapore Armed Forces' Integrated Knowledge-based Command and Control network, a concept similar to the United States Department of Defense's
network-centric warfare doctrine. The locally developed Combat Management System integrates all the sensors and weapon systems on board, and a dual
Fast Ethernet data transfer system forms the backbone of this system. This increases
battlespace awareness and allows little time for the enemy to react due to the short sensor-to-shooter loops.
Armament The frigates are equipped with 2
Sylver A43 8-cell modules
vertical launching systems (VLS) which can launch the
MBDA Aster 15 and 2
Sylver A50 8-cell modules VLS which can launch either the
MBDA Aster 15/30. Both the Aster 15 and 30 share the same warhead, active RF seeker and terminal dart providing the Formidable-class frigates with an all-round anti-missile and anti-air capability to ensure self-defence and fleet protection against swarms of anti-ship missiles and multiple aircraft. The Aster 15 is a short-to-medium range
surface-to-air missile with a range of about 30 km (16 nmi), providing the Formidable-class frigates with self and local area air defence while the Aster 30 is a short-to-long range
surface-to-air missile with a range of about 120 km (64 nmi) providing area and extended area air defence. The frigates are equipped with
Boeing Harpoon missiles and
OTO Melara 76 mm guns for surface defence. The Harpoon missile has a range of and uses active radar guidance. It is armed with a warhead. There is space for as many as 24 Harpoon missiles at the center of ship making it the most well armed ship of its class. The Harpoon missiles will be replaced with the
Blue Spear SSM co-developed by
IAI and
ST Engineering as part of the Formidable-class ongoing mid-life upgrade (MLU) programme, giving the frigates additional beyond-line-of-sight (BLOS) as well as sea and land attack capabilities. The 76 mm gun fires shells to a maximum range of at a firing rate of up to 120 rounds per minute. As part of the mid-life upgrade programme, the Formidable-class frigates' 76 mm main gun will be replaced with the OTO Melara 76 mm gun with STRALES system which uses Driven Ammunition Reduced Time of Flight (DART) projectiles that are guided by a radio beam that follows the target through a homing system to engage high-speed, maneuvering drones, missiles, and fast-moving, small, and agile vessels of ranges up to 5km. The frigates are also equipped with the
EDO Corporation active low frequency towed sonar to enable long range submarine detection and classification, as well as
EuroTorp A244/S Mod 3 lightweight torpedoes fired from two B515 triple-tube launchers hidden behind the bulwark. The frigates are equipped with
Sikorsky S-70B naval helicopters, an international derivative of the
United States Navy Sikorsky SH-60B Seahawk. The Ministry of Defence signed a contract with
Sikorsky Aircraft Corporation in January 2005 to acquire six of these helicopters, which will be organic to the frigates. Each of these naval helicopters are equipped with a Telephonics
AN/APS-143 Ocean Eye X-band maritime surveillance and tracking radar, a
L-3 Communications Helicopter Long Range Active Sonar (
HELRAS) dipping sonar, EuroTorp A244/S Mod 3 torpedoes and a
Raytheon AAS-44 electro-optic system to provide infrared detection and tracking. The naval helicopters will be raised as a squadron in the Republic of Singapore Air Force and piloted by air force pilots, but the system operators will be from the Navy. ==Mid-life upgrades==