The Ada class (also known as the MILGEM project), is a Turkish national warship program, the purpose of which was to build a modern littoral combat ship with indigenous anti-submarine warfare and high-seas patrol capabilities, extensively using the principles of stealth technology in its design. Three Ada-class corvettes have already been commissioned by the Turkish Navy and more are scheduled to enter into service in due course. The corvettes of the MİLGEM project are named the Ada class (ada means island in Turkish). The lead ship of the class, TCG Heybeliada is named after Heybeliada Island, where the Turkish Naval High School is located. The project covers the construction of four corvettes (Ada class), eight frigates which four (TF-100 class) and four (TF-2000 class) for the Turkish Navy, with possible exports to other countries. The first three ships of the class, TCG Heybeliada, TCG Büyükada and TCG Burgazada were built by the Istanbul Naval Shipyard Command.

The project is generally described as the subclasses of multi-purpose warships capable of sustaining a sea war in a littoral combat environment. MİLGEM Project Office (MPO) of the Istanbul Naval Shipyard Command designed and developed the vessel platform. MİLGEM’s design concept covers a multipurpose patrol warship, which can be deployed in a range of missions, including reconnaissance, surveillance, target identification, early warning, anti-submarine warfare, surface-to-surface and surface-to-air warfare, and amphibious operations. It features a steel hull and fragmentation resistant composite superstructure. Fore and aft masts and the funnel have been constructed with sea resistant aluminium alloys. The warships of the MİLGEM project are designed to fully operate at sea state 5 and partially operate at sea state 6. Reduction and management of the ship signatures was taken as the major input during the whole design phase. Many classified precautions were taken in order to reduce hydrodynamic, acoustic, magnetic, IR, radar signatures, and therefore, to achieve the specified level of stealth feature. Locally designed degaussing system minimizes the magnetic signature for protection against the magnetic mines.

The ships are driven by a RENK CODAG Cross Connect propulsion plant. It consists of a gas turbine rated at 23,000 kilowatts (31,000 hp) and two diesel engines rated at 4,320 kW (5,790 hp). Each diesel engine drives one controllable pitch propeller via a two speed main reduction gear. The cross connect gear splits the power from the gas turbine via both main reduction gears to the two shafts. The ship can be operated in Diesel mode, in single gas turbine mode or in CODAG mode where diesel and gas turbine are providing a combined power of 27,640 kW (37,070 hp). The design concept and mission profile of the Ada-class corvette bears similarities with the Freedom-class littoral combat ship developed by Lockheed Martin as the first member of the next generation of U.S. Navy warships; though the Ada-class corvettes are more heavily armed and are equipped with more capable radar and sonar systems, while the Freedom class has a higher speed and variable mission modules.

GENESIS (Gemi Entegre Savaş İdare Sistemi, i.e. Ship Integrated Combat Management System), a network-centric combat management system developed by Havelsan and originally used in the upgraded G-class frigates of the Turkish Navy, was contracted for the first two Ada-class corvettes on May 23, 2007. The MİLGEM project warships have an indigenous hull mounted sonar developed by the Scientific and Technological Research Foundation of Turkey. Sonar dome has been developed and produced by STM’s subcontractor ONUK-BG Defence Systems, extensively employing nano-enhanced Fiber Reinforced Polymer.[13] The Ada class features a electronic chart precise integrated navigation system (ECPINS) supplied by OSI Geospatial.[14] Integrated Platform Management System (IPMS), delivered by STM’s subcontractor Yaltes JV, monitors and controls machinery, auxiliary systems, electrical power generation and distribution. The main systems integrated in IPMS include a power management system, fire detection system, fire fighting and damage control system, CCTV system and stability control system.