Malfunction on UK Nuclear-Armed Submarine Raises Safety Concerns

 24. 11. 2023      Category: Naval forces

Four days ago, the BBC reported a significant incident involving a Royal Navy nuclear submarine, highlighting potential safety concerns in the UK's nuclear deterrent fleet. The malfunction occurred over a year ago on an unnamed Vanguard class submarine, which is part of the fleet carrying the UK's Trident nuclear missiles.

The Incident Details

According to a defence source, the submarine experienced a "concerning" malfunction while preparing for patrol. The main depth gauge failed during a dive, although a secondary system continued to function. This failure is particularly alarming as submarines must withstand extreme ocean pressures, and accurate depth measurement is crucial for safe operation. The incident was serious enough that the submarine was reportedly diving towards its "crush depth" before the crew was alerted to the problem.

Safety Measures and Redundancy Systems

The Royal Navy has emphasized that its submarines are equipped with redundancy systems to prevent such malfunctions from escalating into disasters. These systems appeared to have functioned correctly in this instance, preventing a potentially catastrophic situation.

Official Response and Investigation

Following the incident, the Royal Navy conducted an investigation, the details of which have not been publicly disclosed. The Ministry of Defence (MoD) typically does not comment on submarine operations, maintaining a policy of secrecy. However, in response to this incident, the Royal Navy assured that the safety of its personnel remains its highest priority and that its submarines continue to meet operational commitments.

Previous Issues with HMS Vanguard

This is not the first time concerns have been raised about the Vanguard class submarines. In January of this year, a "defect" was discovered and subsequently repaired on HMS Vanguard, the lead boat of the class, during maintenance work. This defect was reportedly related to previous work done on the vessel, which had just completed a seven-and-a-half-year refit at Devonport dockyard.

Picture: HMS Victorious - the Vanguard class submarine in the Clyde estuary - 2003 | LA(phot) Mez Merrill/MOD

Implications for Naval Safety and Security

The recent malfunction, coupled with the earlier reported defect on HMS Vanguard, raises questions about the overall safety and reliability of the UK's nuclear-armed submarine fleet. These submarines, normally manned by a crew of 132 officers and men, play a critical role in the UK's national security strategy. Incidents like these underscore the importance of rigorous maintenance, continuous monitoring, and transparent reporting to ensure the safety and operational readiness of these strategic assets.


While the Royal Navy has systems in place to handle such malfunctions, and the recent incident was contained without any reported injuries or broader safety compromises, it nonetheless serves as a reminder of the inherent risks associated with nuclear submarines. As these vessels continue to be a cornerstone of national defense, maintaining their safety and reliability remains a top priority for the Royal Navy and the Ministry of Defence.

 Author: Michal Fencl