TCB Marlin SİDA (TCB-1101) is a Turkish unmanned combat surface vessel (UCSV) of the Turkish Naval Forces, commissioned in January 2024.
The UCSV (Turkish: Silahlı İnsansız Deniz Aracı, SİDA) was projected by the Defence Industry Agency of the Ministry of Defense, and built in the Sefine Shipyard at Altınova, Yalova Province in cooperation with the state-owned defence systems company Aselsan for the needs of the Turkish Naval Forces.
Marlin SİDA took part at the "NATO Dynamic Messenger 2022" Exercise held at Tróia Peninsula, Portugal, and displayed her electronic warfare abilities.
On 6 January 2023, a solid-propellant rocket-powered missile Kuzgun-KY, developed by TÜBİTAK-SAGE, was test fired from the UCSV.
At a ceremony held on 9 January 2024, she entered service in the Turkish Naval Forces as the first unmanned surface vessel with the hull number TCB-1101 and name Marlin SİDA.
The vessel features autonomous navigation capability and high maneuverability. She is long, has a beam of, a displacement tonnage of and payload capacity of . She can cruise at a speed up to within a range of with an endurance of 72 hours. The vessel is powered by two Diesel engines. She features dynamic positioning system KARETTA, anti-jam system GNSS and active stabilization system. She is armed with a 12.7 mm remote controlled weapon station, long range guided missiles, light torpedo, and is equipped with Electronic warfare support system and Sonobuoy.