British army forced to halt use of Ajax tanks after soldiers get sick during drills

The UK Ministry of Defence (MoD) has suspended the use of the British Army’s Ajax armoured vehicles after soldiers reported troubling symptoms linked to excessive noise and vibration during a recent training exercise.

The decision comes at a sensitive moment for the programme—just days after officials announced the vehicles had finally reached initial operating capability (IOC) following years of delays, redesigns and cost overruns, as reported by the Army Technology publication.

An MoD spokesperson confirmed that a “small number of soldiers” participating in an exercise on Salisbury Plain in Wiltshire reported symptoms of noise and vibration exposure. The exercise was immediately halted, and all personnel underwent medical checks. According to the ministry, 30 soldiers presented symptoms, with some reportedly emerging from the vehicles vomiting and others visibly shaking after the drill.

UK Minister for Defence Readiness and Industry Luke Pollard ordered the immediate suspension. Under the temporary halt, the Ajax fleet cannot be used in training or exercises for at least two weeks while a formal safety investigation is carried out. Limited controlled testing will continue in order to determine the root cause of the symptoms.

The timing of the setback is particularly damaging, not only for the MoD but for the British Army’s broader modernisation effort. Ajax is intended to be a cornerstone of the Army’s future combat structure, delivering a family of advanced armoured reconnaissance vehicles equipped with cutting-edge sensors and communications systems.

Callum Kaye, defence analyst at GlobalData, is cited to have said that the system is of “critical importance” to British Army doctrine, designed to serve as the armoured cavalry element within the 3rd Deep Strike Reconnaissance Strike Brigade.

Kaye noted that although “at least an interim form of soundproofing could be implemented relatively quickly,” persistent problems risk undermining the brigade’s ability to carry out reconnaissance-in-force missions—one of its central operational roles.

Manufactured by the American defence manufacturer General Dynamics in Merthyr Tydfil, the multi-million-pound Ajax vehicles were originally expected to enter service in 2019. The MoD’s £5.56 billion order covers 589 vehicles across six variants, intended to perform roles ranging from reconnaissance to joint fires coordination.

Yet the programme has been mired in technical issues for years, particularly vibration and noise levels that exceed acceptable limits for safe operation.

These problems have caused multiple pauses in testing and development since the late 2010s. Previous safety advisories instructed crew members to wear double ear protection and follow other precautionary measures while operating the vehicles. Dozens of personnel have required medical assessments over the course of the programme’s development.

The latest suspension is seen as a major blow for the government, which has been attempting to restore confidence in the UK’s defence readiness amid concerns about the Army’s declining capabilities.

Analysts have repeatedly warned that the Army suffers from critical equipment gaps, including shortages of 155mm artillery, outdated armoured fleets and insufficient stockpiles across several key systems. The Ajax issues add to the impression of a force struggling to modernise at a time of heightened global instability.

The programme’s troubled history dates back more than a decade. Originally conceived in the late 2000s as the Scout SV programme—a supposed “military-off-the-shelf” procurement—the project has since undergone extensive redesign and modification. The first prototype was unveiled in 2015, but technical problems emerged almost immediately during testing. By 2021, an official report found that soldiers had suffered hearing loss, nausea and joint pain linked to the platform’s vibration levels, prompting a lengthy pause and renewed scrutiny.

Although earlier rounds of corrective work allowed the MoD to declare initial operating capability in late 2024, the sudden resurgence of health concerns now casts doubt over the durability of those fixes. Investigators will focus on whether the recent symptoms stem from previously known flaws, newly introduced problems or operational conditions specific to the Salisbury Plain exercise.

The MoD has said that the safety of personnel remains its primary concern and emphasised that the temporary pause is part of a precautionary approach. Further updates are expected once the formal investigation concludes.

By Nazrin Sadigova