In early 2006 the MoD started a Sustained Surface Combatant Capability (S2C2) programme which explored synergies between the FSC and other needs, for minesweepers, patrol ships and survey ships. By early 2007 this had crystallised into the three requirements; C1, C2 and C3. The C1 was to be an anti-submarine warfare task group-enabled platform and would displace around 6,000 tonnes. C2 was to be a more general purpose platform displacing somewhere in the region of 4–5,000 tonnes, and C3 was to be a Global Corvette to replace a larger number of smaller vessels in service, such as minesweepers, patrol and survey ships. The Global Corvette was to displace around 2–3,000 tonnes. The C3 concept found its roots in early 2004 when the MoD issued a Request for Information (RFI) for a smaller class of ship known as the Global Corvette. Low running costs and the ability to operate forward in shallow, coastal areas where larger ships cannot, were both important. BAE Systems, VT Group, Thales and Rolls-Royce responded in autumn 2004 with concepts ranging from a well equipped Offshore Patrol Vessel (OPV) of 1,500 tonnes to an advanced and very capable "corvette" of 3,000 tonnes, along the lines of the USN's Littoral Combat Ship programme (LCS).