The Preveze-class submarines form a critical component of the Turkish Navy’s undersea warfare capability. Commissioned in the 1990s, these platforms are based on the German Type 209/1400 Mod design and have long provided effective anti-surface and anti-submarine capabilities. However, the evolution of naval warfare — including network-centric operations, advanced sensor fusion, low-signature threats, and increased electronic warfare activity — necessitated a structured mid-life modernization.

This program is not merely a system replacement effort; it represents a doctrinal and digital transformation aimed at maintaining operational relevance into the 2030s.

Operational Purpose and Role

The modernization ensures that the Preveze-class submarines can continue to perform:

Anti-submarine warfare

• Anti-surface warfare
• Strategic deterrence patrols
• Intelligence, surveillance and reconnaissance missions
• Special forces deployment

The focus areas include enhanced fire control, improved navigation accuracy, secure communications, and integration into network-enabled operational structures.

Doctrine and Concept of Operations

The upgraded submarines are intended to operate within a network-centric framework alongside surface combatants, maritime patrol aircraft, and other naval assets. The integration of satellite communication masts and floating antenna systems enables data exchange with reduced exposure, enhancing survivability and mission endurance.

This capability supports:

• Joint maritime operations
• Extended submerged endurance with communication capability
• Integrated battlespace awareness

Platform Architecture

The modernization scope includes upgrades or replacements of:

• Inertial Navigation System
• Attack and search periscope systems
• Satellite communication mast
• Floating antenna system
• Emergency underwater communication system
• Salinity–Depth–Density measurement system
• Chilled water system
• Static converter
• Air refresh system

These upgrades are designed to function within an integrated combat management architecture, with emphasis on indigenous system development and engineering autonomy.

Survivability and Protection Approach

Although hull structure and primary propulsion remain unchanged, survivability improvements include:

• Increased navigation precision
• Secure and low-probability-of-intercept communication
• Updated sensor capabilities
• Enhanced system reliability through upgraded power and cooling systems

Detailed electronic warfare resistance parameters are not publicly disclosed.

Integration Ecosystem

The modernized submarines are expected to operate in conjunction with:

• National torpedo systems
• Integrated naval command-and-control networks
• Maritime patrol platforms
• Surface combatants

Indigenous weapon integration is a strategic objective of the program.

Advantages and Limitations in Modern Threat Environment

Advantages:

• Digitally upgraded architecture
• Indigenous system integration
• Improved navigation accuracy
• Enhanced communication capability

Limitations:

• No Air-Independent Propulsion system
• Original 1990s hull design
• Conventional diesel-electric propulsion

The program upgrades existing capabilities rather than transforming the submarines into a next-generation design.

Detailed Technical Information

Dimensions and Displacement

• Class: Type 209/1400 Mod derivative
• Displacement: Approximately 1,400 tons (surfaced; higher when submerged)
• Length: Approximately 62 meters

Exact platform-specific values may vary.

Propulsion System

• Diesel-electric propulsion
• No Air-Independent Propulsion

Detailed engine and generator specifications are not publicly disclosed.

Performance

• Maximum submerged speed: Approximately 21 knots
• Operational diving depth: Not publicly disclosed
• Endurance and range: Mission-dependent

Sensors and Detection

Modernization includes:

• Upgraded inertial navigation system
• Enhanced periscope and electro-optical systems
• Oceanographic measurement systems

Detailed sonar specifications are not publicly disclosed.

Engagement and Weapons

• 533 mm torpedo tubes
• Heavyweight torpedo capability
• Potential integration of indigenous torpedoes

Fire control modernization details remain limited in public sources.

Command and Control

• Integrated combat management system
• Satellite communication mast
• Floating antenna for underwater communications

Specific data link standards are not publicly disclosed.

Logistics and Shipyard Activities

Modernization is conducted in Turkish naval shipyards under national industrial leadership. Structural inspections, maintenance and system upgrades are performed concurrently, contributing to domestic submarine sustainment expertise.

Frequently Asked Questions

What is the purpose of the Preveze modernization?

• It extends operational life, upgrades combat systems, improves communication capabilities, and enhances compatibility with network-centric naval operations.

Does the modernization include Air-Independent Propulsion?

• No. According to publicly available information, AIP integration is not part of the program.

Which systems are being upgraded?

• Navigation systems, periscopes, satellite communication masts, floating antennas, power conversion units, and various auxiliary systems.

How many submarines are included?

• Four submarines: TCG PREVEZE, TCG SAKARYA, TCG 18 MART and TCG ANAFARTALAR.

How long will the submarines remain in service?

• Mid-life upgrades typically extend service life by 10–15 years, though exact timelines are not publicly disclosed.

Is indigenous weapon integration planned?

• Yes, integration of domestically developed weapon systems is one of the strategic objectives, though technical details remain limited in open sources.

Sources

• Official statements by STM
• ASELSAN project announcements
• HAVELSAN defense project releases
• ASFAT official communications
• Public Turkish Navy inventory information