$45bn Hunter-class Frigates have no set speed, range requirements

Defence officials also reveal that if the Hunter-class program is further delayed, it will be recommended as a ‘project of concern’.

An artist's impression of the BAE Systems SEA 5000 Future Frigate. Picture: Supplied

Defence officials have revealed the nation’s $45bn Hunter-class frigate program has no set speed or range requirements, and if the program is further delayed, they will recommend it to be listed as a “project of concern”.

The admissions in a Senate estimates hearing came as independent Senator Rex Patrick accused a Defence official of lying in previous evidence suggesting the ship had no weight or propulsion problems.

Defence officials were interrogated over a bombshell internal engineering report, revealed exclusively by The Australian, that the frigates would be “substantially” slower, have a shorter range than originally intended, and could be vulnerable to detection by enemy vessels.

But Defence’s national shipbuilding program manager Tony Dalton said the ship was not failing to meet Defence’s requirements, because those were not set in stone.

He said the Hunter-class frigate’s performance benchmarks would be determined by those of the yet-to-be-completed British Type-26.

“The specifications that we have are derived specifications, so we don’t have a number for some of these things in the contract because it is a derived specification,” Mr Dalton said.

Last July, Defence Minister Peter Dutton approved a delay in commencement of construction on the first boat, from December 2022 to June 2024, but the report said this deadline was now tight.

Mr Dalton said he would also not hesitate to recommend the program for listing on Defence’s “projects of concern” list should it experience further slippage.

“From my perspective if we were to experience further delay we would absolutely be looking at discussing with government about adding this project to the projects of concern list,” he said.

The System Design Review Exit report revealed weight concerns with the ship, due to modifications of the original Type-26 design under construction for the British Navy, would place huge strain on the propulsion and generating systems, leaving it underpowered.

Under questioning from Labor’s Kimberley Kitching, Hunter-class program manager Sheryl Lutz agreed the ship’s “weight is a problem”, and that the report revealed serious concerns that shipbuilder BAE Systems was struggling to cope with design changes.

“That was the engineering team’s assessment, and we asked them to do that assessment,” she said.

Senator Patrick said this conflicted with evidence Ms Lutz gave about the program in June last year.

“I will read back what you said: ‘All of the modelling has been done, there is no impact on the propulsion chain … We are still meeting the same performance requirements in terms of range and speed’,” he said.

“That report says that is not correct. That report tells me you lied to this committee.”

Senator Patrick refused to withdraw the comment when challenged by committee chair Eric Abetz, saying he was considering referring Ms Lutz to the privileges committee based on her previous evidence.

Ms Lutz said the concerns were not evident last June.

Defence Minister Peter Dutton previously described the report as a “low level” internal document.

But Mr Dalton agreed with Senator Kitching that it was “absolutely” important, revealing “absolute risks which we need to concentrate on”.

The officials confirmed there were no “Plan B” alternatives under consideration for the frigates, as there was for the now-cancelled Attack-class submarines, which have been dumped for planned nuclear boats.

Labor Defence spokesman Brendan O’Connor said it was reckless for the government not to have a back-up plan.