TAIS shipyards’ role in the Istif-class frigates
Quick answer: The İstif-class frigates are the frigate leg of the MİLGEM program, derived from the Ada-class corvettes, and TAIS Shipyards is directly involved in the class’s serial production. Ships two to four — TCG İzmir (F-516), TCG İzmit (F-517) and TCG İçel (F-518) — were built simultaneously at TAIS partners Anadolu, Sedef and Sefine under a model with STM as prime contractor. The first ship, TCG İstanbul (F-515), entered service with the Turkish Naval Forces in January 2024.
What is the İstif class?
The İstif (İ) class is an enlarged-hull evolution of the MİLGEM design lineage. According to open data compiled by the Turkish-language Wikipedia, the class stands out against the Ada class through higher tonnage, greater guided-missile capacity and a 16-cell vertical launching system (MİDLAS). A series of eight ships in total is planned. Figures reported by The Defense Post put the ships at 113.2 meters in length, 14.4 meters in beam and 3,150 tons displacement; speed exceeds 29 knots, and the main weapons load includes ATMACA anti-ship missiles.
Production model: simultaneous construction at three yards
For ships two to four, the Presidency of Defence Industries appointed STM as prime contractor, with block construction and outfitting work distributed to the three private yards of the TAIS partnership. According to a Defense News report of January 2023, each of the three frigates was assigned to one yard, with simultaneous construction planned on a 36-month schedule. Instead of serial production tied to a single slipway, this model aims to compress the timeline through parallel building.
| Ship | Pennant number | Building yard | Status (per sources) |
|---|---|---|---|
| TCG İstanbul | F-515 | Istanbul Naval Shipyard | Commissioned January 2024 |
| TCG İzmir | F-516 | Anadolu Shipyard (ADİK) | Launched; fitting out |
| TCG İzmit | F-517 | Sedef Shipyard | Launched; fitting out |
| TCG İçel | F-518 | Sefine Shipyard | Under construction/outfitting |
| TCG Karadeniz | F-520 | Sedef Shipyard | Launched in 2026 |
A distinction matters here: the first ship of the class, TCG İstanbul, was built at the Istanbul Naval Shipyard — a military yard — and the TAIS partners’ role began with the second ship. According to Army Recognition, TCG Karadeniz (F-520), one of the follow-on ships in the series, was launched at Sedef Shipyard in 2026. The table shows that the private-yard leg of serial production runs through the consortium partners.
MİLGEM heritage and design lineage
The first four ships of the Ada class, the corvette leg of the MİLGEM program, were built at the Istanbul Naval Shipyard. The İstif class was developed on a stretched version of that hull, with the air-defense load increased through a vertical launching system. Export versions of the same design family are being built for the Pakistani and Ukrainian navies by different contractors; the work share in those programs is separated out with sources in the export file.
Within TAIS’s own catalog, the product closest to the İstif class is the Frigate-115 version of the BORA corvette and frigate family; the official website lists it at 115 meters in length and 3,000 tons displacement. For the consortium’s overall structure, see the What is TAIS Shipyards file.
What the program means for the Turkish Navy
The İstif class is the Turkish Naval Forces’ program for renewing its frigate inventory with a national design. Once the series is complete, eight ships are planned to join the fleet. The program also stands as the first large serial-production experience gained by private yards in major combatant construction; three yards building the same class in parallel established a new work model for Turkey’s naval shipbuilding industry.
Frequently asked questions
Who is building the İstif class?
The first ship was built at the Istanbul Naval Shipyard. Ships two to four were built at TAIS partners Anadolu, Sedef and Sefine with STM as prime contractor.
What is TAIS’s role in the İstif program?
The consortium partners took on the block construction, launch and outfitting of the ships; each yard was assigned one vessel, with construction carried out simultaneously.
How many ships will the İstif class comprise?
Open sources state that a series of eight ships in total is planned. The first ship entered service in 2024; the follow-on ships are in construction and outfitting.
What weapons does the İstif class carry?
According to open sources, ATMACA anti-ship missiles and a 16-cell MİDLAS vertical launching system. Parts of the detailed configuration were not officially disclosed.
Has the İstif class been exported?
In January 2026, TAIS and Barzan Holding signed an agreement worth roughly 1 billion dollars covering two İstanbul-class frigates for Indonesia.
Sources and verification note
Ship-to-yard assignments and numerical data rely on the sources below; where details do not appear in these sources, the phrase “not officially disclosed” is used. Accessed: August 13, 2026.
- Turkish Wikipedia, “İstif sınıfı fırkateyn”: https://tr.wikipedia.org/wiki/%C4%B0stif_s%C4%B1n%C4%B1f%C4%B1_f%C4%B1rkateyn
- STM, “MİLGEM İstif Sınıfı Projesi / TCG İstanbul (F-515)”: https://www.stm.com.tr/en/tcg-istanbul-f-515
- Defense News, “Turkey chooses local shipyards to build three frigates” (24.01.2023): https://www.defensenews.com/industry/2023/01/24/turkey-chooses-four-shipyards-to-build-three-frigates/
- Army Recognition, “Türkiye launches sixth Istanbul-class frigate TCG Karadeniz at Sedef Shipyard”: https://www.armyrecognition.com/news/navy-news/2026/tcg-karadeniz-f520-istif-class-frigate-launch-turkey-milgem
- The Defense Post, “Turkey’s TAIS Signs $1B Frigate Agreement With Qatar’s Barzan for Indonesia” (21.01.2026): https://thedefensepost.com/2026/01/21/tais-frigate-agreement-indonesia/
- TAIS official website, Frigate-115 BORA: https://www.taisshipyards.com/en/frigate-115-bora
