LONDON – British Ministry of Defence officials have confirmed the military will buy more than the 48 F-35B combat jets already on order, but they were reluctant to be drawn on exactly when and how many aircraft may eventually be involved when they gave evidence to the parliamentary Defence committee Dec 8.

The number and profile of a future order will in part be decided by the outcome of assessment work the British are doing on their future combat air strategy, Air Marshal Richard Knighton, the deputy chief of the defense staff for capability, told the committee hearing.

“We know we need to increase the  number of F-35Bs to support the [Royal Navy] carrier through to its out-of-service date. The precise number will dependent a bit on the work we do and the investment we are making  on the FCAS,” he said, referring to the UK-led Tempest program. “We expect to make a definitive judgement around the total future fleet in the 2025 timeframe,” Knighton added.

Britain originally committed to buy 138 of the Lockheed Martin short take-off vertical landing combat jets to equip a joint force of Royal Navy/Royal Air Force aircraft. The F-35Bs are principally scheduled to equip two new 65,000 tonne aircraft carriers.

Knighton said the final number could be up to the 138 commitment, or less. “We need to do the analysis  and work to ensure we get the right number,” he told the committee.

To date the British have ordered 48 of the jets. So far 21 have been delivered, with the remaining aircraft under contract due to be delivered by 2025.

The first of the carriers, HMS Queen Elizabeth, is scheduled to make its first operational deployment next year to the Indian Ocean with a mix of British and U.S. Marine Corps F-35Bs onboard.

The British plan to only deploy one carrier at any given time due to a lack of resources. Some 24 jets are expected to be the full complement of fighters on board even though senior Royal Navy officers have said the ships could operate with up to 72 jets at a squeeze.

Knighton said the British “will be able to operate up to 24 aircaft from 2023 onwards, that’s been the milestone for some time. If we want to order aircraft to be delivered in the later part of the decade we will need to allocate some of the funding that we anticipate [being available] to do that. That is part of the analysis and thinking that we are doing with ministers at the moment.”

Defence committee chairman Tobias Ellwood commented on the small number of jets the British plan to operate from the carriers, saying: “We are going to end up with a fantastic looking aircraft carrier, very bespoke aircraft, but not many of them onboard.”

Sir Stephen Lovegrove, the permanent secretary at the MoD, told the committee that while it was certain Britain would order more jets it wouldn’t be anytime soon.

“It’s inevitable we are going to buy more than 48 jets, otherwise we won’t be able to operate the carriers probably. Not for the next four years, though, it’s about the 48 [jets on order].”

“There are certainly plans and conversation with Lockheed Martin about the future purchases, we just haven’t got to the stage of contract yet,” said Lovegrove.

The permanent secretary, the MoD’s top civil servant, suggested the aircraft wouldn’t be available quickly even if Britain had the funds to buy them.

“Even if tomorrow we discover the magic money tree and we decided we wanted to buy 200 F-35B we couldn’t get them just like that anyway. They take forever to manufacture, we will make our orders when they are available,” he said.

Other take-aways from the committee hearings included MoD permanent secretary Sir Stephen revealing that Defence Secretary Ben Wallace is to make a statement soon outlining program cuts ahead of publication of the government’s integrated strategy review set for publication in late January.

The government recently announced a £16 billion increase in MoD funding over the four years starting in April 2021, much of that will go to equipment and other capital programs.

Despite that, Lovegrove signaled there were some painful cuts coming to programs that don’t support the government’s swing towards cyber, space , underwater and other high-tech programs and away from legacy platforms.

Lovegrove said the time for “sentimentality” was over on legacy programs. There were some “difficult decisions to be made” in what he termed “disinvestment.”

Pentagon officials who had been kept informed of British intentions were said to have approved of the British moves.

Knighton said a program to update the British Army’s Challenger 2 fleet is due to go the MoD’s investment approvals board in the next few days. The program was in good shape, he said.

A reduction in Challenger 2 numbers has been touted by analysts and media as being in the government sights for months.

Andrew Chuter is the United Kingdom correspondent for Defense News.

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