Portugal Makes Waves in Arctic: First Under-Ice Submarine Operation Highlights NATO's Strategic Needs

Introduction

The Portuguese Navy has marked a significant milestone with its first-ever deployment of a submarine to the Arctic, showcasing the importance of conventional submarine operations for NATO.

Deployment Overview

The Type 209PN Tridente-class SSK NRP Arpão undertook a 70-day mission under Operation ‘ARCTIC 2024’. This mission aimed to operationally explore the submarine's capabilities in the Arctic region. Admiral Henrique Gouveia e Melo, Portugal’s Chief of Navy, emphasized the deployment's role in reinforcing NATO's deterrence and defense strategies.

Arpão crew members are pictured onboard during the deployment, along with Admiral Henrique Gouveia e Melo, Portugal’s Chief of Navy (second left). Pre-deployment training for the crew encompassed safe operation of the submarine, optimising the boat’s tactical positioning, and maximising effective use of its sensors. Source: Portuguese Navy.

Mission Phases

The deployment was split into two phases:

• Phase 1: 22 days supporting NATO's Operation ‘Brilliant Shield’, aimed at reinforcing alliance defense.
• Phase 2: Operating within the Arctic Circle, including the marginal ice zone (MIZ) and under the ice shelf.

A key stop was in Nuuk, Greenland, for maintenance and mission planning, highlighting the logistical challenges of operating in remote regions.

Preparation and Training

Prior to the mission, Arpão underwent extensive preparations, including:

• Enhanced maintenance for the Arctic environment.
• Installation of protective barriers and high-frequency sonar for ice detection.
• Seven months of crew training to adapt to new operational procedures in icy conditions.

Navigational Challenges

Operating in the Arctic presented various challenges:

• Ice coverage complicates navigation and sonar operation.
• The MIZ features a mix of ice types, requiring constant monitoring of ice conditions.
• Climate change has altered underwater acoustics, affecting sonar efficiency due to changing salinity and temperature.

Operational Impact

The deployment demonstrated that conventional submarines like Arpão provide a strategic advantage in Arctic warfare, particularly as a counter to nuclear-powered submarines, which can hide under ice. NATO's Allied Maritime Command confirmed that the mission successfully monitored non-NATO military platforms in the area, achieving all surveillance objectives.

NRP Arpão (Credit: Danish Arctic Command)