Almost 200 more personnel involved in the British Army's delayed £5.5bn Ajax armoured fighting vehicle programme have been contacted for an urgent hearing assessment.
Defence Procurement Minister Jeremy Quin wrote in an update to Parliament that 121 personnel had initially been identified as requiring hearing assessments due to noise exposure on Ajax.
"Subsequently, the MOD [Ministry of Defence] broadened the scope of those who should be tested to all those who had been exposed to noise on Ajax," he added.
"To date, a further 189 individuals have been identified that should be offered an assessment, giving a total number of 310 personnel."
Mr Quin said 304 of those had been contacted and the remaining six, who have recently left the service, are being traced.
However, Ben Barry, Senior Fellow for Land Warfare at IISS, told Forces News if you read Mr Quin's statement, "you will see that these problems were known about two or three years ago".
"And there is therefore a question about whether enough was done two or three years ago to resolve them," he said.
"It's quite clear that the programme, if you like, is being put into special measures."
However, he said he blames the MOD and Defence Procurement rather than the Army for an ill-defined defence industrial strategy and a loss of home-grown design expertise in armoured vehicles.
Mr Barry added he found it "difficult to understand" by the length of time it’s taking to resolve the issues with Ajax.
Trials of the Ajax vehicle family have been on hold at Millbrook Proving Ground since June due to noise concerns but Mr Quin said the trials are expected to resume "imminently".
Tests of the programme were previously "paused as a precautionary measure" between November 2020 and March 2021.
Watch: Ajax manufacturers: 'The vehicles do work'.
Mr Quin said the British Army had been aware of the vibration issue as early as 2018.
He said a report from the MOD’s director of health and safety is expected to detail an "overlapping" of the demonstration and manufacturing phases within the programme.
Other themes could include the "equal status" of safety alongside cost and schedule, and the importance of "independent certification" in proving capability, he added.
Chris Evans MP, Labour's shadow defence procurement minister, said: "The Ajax programme is in chaos.
"It is now clear the problems have been known about for years and nothing was done. With ministers admitting the delivery of Ajax is entirely in doubt, this is another nail in the coffin for the Government’s defence and foreign policy strategy, published just six months ago."
Dr Jack Watling, research fellow for land warfare at the Royal United Services Institute, compared the management of vibration in an armoured vehicle to "conducting an orchestra".
"It is clear that the systems engineering has resulted in the vibration peaking at cruising speeds, leading to crew feeling the prolonged effect, and that it is excessively concentrated on certain components like the idlers," he wrote on Twitter.
Watch: Trials of Ajax were suspended in June.
The Ajax programme consists of seven vehicle models, with six variants having been due to enter service in 2020.
But Mr Quin said a long-term fix is needed for the noise and vibration problems before the vehicle's initial operating capability can be declared.
He said it was not possible to give a "realistic timescale" for when the vehicle would be ready, as there is still "considerable work" to be done.
"Until a suitable suite of design modifications has been identified, tested and demonstrated, it is not possible to determine a realistic timescale for the introduction of Ajax vehicles into operational service with the Army," Mr Quin said.
"We will not accept a vehicle that is not fit for purpose."
He added: "Ajax is an important capability for the Army and we are committed to working with General Dynamics for its delivery."
The manufacturers at General Dynamics will stick to the original £5.5bn contract terms, he continued.
Cover image: File photo of an Ajax armoured vehicle (Picture: MOD).