GDLS UK: Ajax is among the ‘most tested’ combat vehicles produced

With several investigations into the Ajax armoured vehicle coming to an end, it remains unclear where the blame for enduring issues with the platform lie.

Contradictions have crept into public discussions about the stagnant programme.

Addressing the UK Public Accounts Committee on 23 March, Lieutenant General Anna-Lee Reilly, director general for core delivery at Defence Equipment & Support, the procurement arm of the Ministry of Defence, recounted the findings of the British Army’s safety investigation team.

Here, Reilly said personnel failed to operate and maintain the platform to specification during the month-long Titan Storm exercise in November 2025, when complaints of excessive internal noise and vibration levels arose once again.

The problem was not the “wilful ignorance” of soldiers “but part of operating on armour,” Reilly detailed, citing a tangible technical defect, namely the alteration of track tension over time.

Rigorous testing

However, Army Technology has since approached GDLS UK, the manufacturer, which assembles, integrates and tests units at its Merthyr Tydfil plant in Wales.

While the company did not directly address this specific problem intimated to Committee members, it did maintain confidence in platform performance based on their rigorous testing procedures.

The vehicle has completed over 42,000 kilometres of instrumented trials and 30,000 live-fire rounds with military crews, generating a dataset that exceeds global benchmarks and under the most demanding conditions.

“Ajax now holds the most comprehensive safety case of any armoured platform worldwide, covering vibration, acoustics, ergonomics, and crew health,” the company said in a statement. “This is the one of the most tested combat vehicles ever produced.”

Likewise, testing is approved by every party with an interest in the programme.

Since early 2023, GDLS UK has conducted Reliability Growth Trials that demonstrate the reliability of the platform with Army crews. Each vehicle involved is equipped with comprehensive monitoring systems for noise and vibration.

Throughout the trials crews are continually assessed for health and feedback on the vehicle by DE&S, British Army, GDLS UK, and independent experts. At all times, the company concluded, these trials have “evidenced demonstrably safe operation.”

Checks every time the vehicle stops

Looking ahead, the director general continued, commanders will instruct Ajax operators to “do checks every time they stop the vehicle.”

This is absurd for a sovereign programme which is estimated to cost £6.2bn. If the UK Government opt for this solution, then it could detract from the platform’s exportability – a Government priority laid out in the Defence Industrial Strategy.

Ajax has already garnered attention from abroad, with active conversations with multiple potential customers underway.

There are technical solutions too, which Reilly said alterations to include automatic track tensioners. One solution is to add composite rubber tracks, for which, Reilly said, trials will take place at the end of this year to discover whether it is “value for money” and “makes a sustained difference” to the platform. 

However, a leading Ajax trials engineer first referred to such a trial of composite rubber tracks in November, when he said that such a system will be integrated onto the BLACKJAX testbed platform and demonstrated in early December 2025.