Twin Ships

İkiz Gemiler (Çağrı Bey and Yıldırım) refer to the seventh-generation ultra-deepwater drilling vessels, completed in 2024 in South Korea and equipped with the most advanced technology.

Çağrı Bey and Yıldırım vessels have been incorporated under the Turkish Petroleum Corporation (TPAO) to elevate Türkiye's hydrocarbon exploration and production capacity in its maritime zones to a strategic level. These two new platforms, possessing identical high technical capabilities, are designed to operate both in national waters and international waters in line with Türkiye's energy independence goals. Indeed, seventh-generation drilling vessels are highly advanced floating platforms used to access oil and natural gas reserves located thousands of meters beneath the seabed. The "İkiz Gemiler", now part of Türkiye's energy fleet, belong to the class of "seventh-generation ultra-deepwater drilling vessels." This classification reflects their advanced automation systems, safety equipment, and ability to maintain stable operations at depths of thousands of meters even under harsh sea conditions. Çağrı Bey and Yıldırım are defined as critical technological components of Türkiye's "Mavi Vatan" strategy, aimed at ensuring energy supply security and reducing external dependency.^【1】

^{The Newly Added to the Energy Fleet "Yıldırım" and "Çağrı Bey" Vessels (}Anadolu Agency⁾

The Oruç Reis Seismic Research Vessel played a pioneering role in collecting the scientific and technical data underpinning drilling operations. In October 2024, the vessel departed from Istanbul's Dolmabahçe and undertook a continuous and intensive nine-month mission in Somali maritime areas under an intercontinental mandate, covering a licensed area of 4,465 square kilometers.^【2】

Equipped with modern seismic instrumentation, the Oruç Reis employed three-dimensional (3D) seismic data acquisition techniques to produce detailed subsurface geological imaging of the seabed. The vast volumes of digital data collected during this precise survey in three distinct maritime blocks off Somalia were transmitted to data processing centers in Ankara for analysis.

Following the successful completion of the Oruç Reis seismic data collection phase, and in accordance with the state strategy announced by President Recep Tayyip Erdoğan, the first drilling operations in Somali maritime areas are planned to commence within 2026.

According to the operational schedule, the Çağrı Bey Drilling Vessel, which will play the central role in this initiative, is undergoing a comprehensive preparation process at Mersin Taşucu Port. The goal is to complete all preparations by the end of January 2026 and set sail for the first drilling site in Somalia. This transition marks the stage where theoretical data is transformed into tangible discoveries. Technically, the objective of these drills is not only to detect the presence of hydrocarbons but also to determine the commercial scale and fluid properties of the reservoir. Starting from early 2026, the energy potential in ocean depths will be tested using technological capabilities capable of reaching depths of up to 12,000 meters.^【3】

The quartet of vessels — Fatih, Yavuz, Kanuni, and Abdülhamid Han — which played critical roles in the discovery and development of the Sakarya Gas Field, has been strengthened into a powerful fleet with the addition of two new "twin vessels" in 2024 and 2025. With the total number of drilling vessels rising to six, Türkiye has secured the fourth position globally in terms of deepwater energy fleet size and technological capability.^【4】

The newly added vessels, "Çağrı Bey" and "Yıldırım," are equipped with seventh-generation ultra-deepwater drilling technology and possess the capability to operate under the most challenging oceanic conditions. Turkey Petroleum Corporation (TPAO) can now simultaneously conduct production enhancement activities in the Black Sea and exploration operations elsewhere.

The expansion of the fleet has become a key element in extending Türkiye's "Mavi Vatan" doctrine to international waters and fostering intercontinental cooperation. Supported by 11 support vessels, seismic research ships, and floating production units (FPUs), this fleet forms a "fully independent" ecosystem for unlocking the nation's wealth hidden thousands of meters beneath the seas.^【5】

The two newest seventh-generation drilling vessels added to the fleet are named "Çağrı Bey" and "Yıldırım." Announced by President Erdoğan, these vessels are the new vanguards of Türkiye's energy fleet. Arriving in Türkiye on September 28 and December 4, 2024, respectively, both vessels have entered an operational preparation phase at Mersin Taşucu Port. Each is assigned to achieve Türkiye's strategic objectives across different maritime zones with their advanced technological capabilities.

^{Seventh-Generation Ultra-Deepwater Drilling Vessels Yıldırım and Çağrı Bey (}Anadolu Agency⁾

The Çağrı Bey and Yıldırım vessels, now part of Türkiye's energy fleet, belong to the globally recognized "technological marvel" class of seventh-generation ultra-deepwater drilling vessels. Completed in South Korea in 2024, these twin vessels feature hulls measuring 228 meters in length and 42 meters in width, designed specifically for offshore engineering operations.^【6】 Their most distinguishing feature compared to previous generations is their high levels of automation and digital control systems. The vessels' standout technical capability is their ability to drill to a depth of 12,000 meters (approximately 40,000 feet) below sea level.^【7】

To sustain multi-month offshore operations, the vessels are equipped with living quarters capable of accommodating approximately 200 personnel.^【8】 The onboard helicopter deck enables uninterrupted air bridges for crew rotations and emergency logistical support. Additionally, advanced laboratory facilities allow for real-time analysis of extracted samples, providing engineers with immediate scientific data on the subsurface resource's characteristics.

The Çağrı Bey Drilling Vessel represents a concrete and strategic step in Türkiye's "intercontinental energy vision," extending its successes in the Mediterranean and Black Seas to international waters. Tasked under the hydrocarbon exploration and production agreement signed between Türkiye and Somalia, the vessel will fly Türkiye's flag off the East African coast and extend Türkiye's deepwater exploration capabilities to an oceanic scale.

Currently stationed at Mersin Taşucu Port, Çağrı Bey is undergoing a comprehensive operational preparation and technical maintenance process to adapt to Somalia's oceanic conditions. During this phase, the vessel's drilling equipment, dynamic positioning systems, and deepwater well control units are being modernized. According to plans, all preparations are scheduled to be completed by the end of January 2026, after which the vessel will depart for Somalia. A support fleet will accompany Çağrı Bey during this long voyage and drilling operation to ensure logistical support and security.

Çağrı Bey's mission in Somalia is not a random exploration effort but the direct result of the 4,465 square kilometers of data collected by the Oruç Reis Seismic Research Vessel and processed in Ankara. The vessel will drill at specific coordinates identified by seismic data as having high hydrocarbon potential.

^{Seventh-Generation Ultra-Deepwater Drilling Vessel (}Anadolu Agency⁾

The sixth vessel added to Türkiye's deepwater drilling fleet, Yıldırım, has assumed a critical role in the Sakarya Gas Field Development Project, the strategic arena of Türkiye's journey toward energy independence in the Black Sea. Yıldırım will join ongoing operations with the Fatih, Yavuz, Kanuni, and Abdülhamid Han vessels to elevate production capacity to a higher level.

Expected to relocate to Filyos Port, the logistical hub of the Black Sea, in January, the vessel will undergo reassembly of its crane, dismantled for passage through the Turkish Straits, and enter its operational preparation phase. This technical preparation stage involves calibrating Yıldırım's "seventh-generation" technological systems to the Black Sea's deepwater conditions.

Yıldırım's primary mission is to directly support natural gas production in the Sakarya field by commencing its first well completion operations by the end of March 2026. In this capacity, the vessel will carry out "well completion" processes including installation of subsea wellhead systems, connection of subsea pipelines, and preparation of newly drilled wells for integration into the production line.

The arrival of Yıldırım accelerates the second phase of operations aimed at increasing daily production in the Sakarya Gas Field from 10 million to 20 million cubic meters. The vessel will not only drill new wells but also serve as a technological bridge connecting the subsea wells to the Osman Gazi Floating Production Unit (FPU) deployed in the Black Sea. These efforts aim to supply natural gas to eight million households and minimize Türkiye's energy import bill.^【9】

^{Türkiye's Current Energy Fleet (}Anadolu Agency⁾

Türkiye's deepwater energy strategy is not limited to drilling vessels but is built upon an integrated "National Energy Fleet" capable of managing the entire process from exploration to final production. The fleet forms an end-to-end operational ecosystem under the Turkish Petroleum Corporation (TPAO), spanning seismic surveys to well completion, subsea construction to floating platform operations, ensuring full operational independence.

The core of the fleet consists of the Fatih, Yavuz, Kanuni, and Abdülhamid Han drilling vessels, which simultaneously conduct exploration and well completion operations in the Sakarya Gas Field in the Black Sea. These vessels are guided by the Oruç Reis and Barbaros Hayrettin Paşa seismic research vessels, which map the seabed's geology. Oruç Reis, having completed its historic mission in Somalia, has begun preparing for data collection in new areas of the Black Sea, while Barbaros Hayrettin Paşa continues uninterrupted 3D data acquisition across different blocks of the Black Sea.

A critical element distinguishing Türkiye's energy fleet is the "Osman Gazi" Floating Production Unit (FPU), which will manage production from the Sakarya field. This facility processes raw gas extracted from the seabed and transports it to shore, representing the fleet's newest and most sophisticated component. Scheduled to commence full operations in mid-2026, Osman Gazi is central to the goal of increasing daily production capacity in the Black Sea to 20 million cubic meters.^【10】 To support this process, the fleet also includes one high-tech subsea construction vessel.

The continuity of deepwater operations is ensured by 11 modern support vessels in the fleet. These vessels transport critical materials such as fuel, drinking water, cement, and drilling mud to the drilling platforms, while also assuming responsibilities for maritime security and emergency response, including firefighting and oil spill containment. Thanks to this comprehensive structure, Türkiye does not merely discover resources in the deep sea but also constructs the entire engineering infrastructure required to install subsea wellhead systems and pump gas to terminal facilities using its own capabilities.