One source described the situation as a "general collapse" in the flow of new recruits into the service, but the navy rejected this characterisation, while conceding there was a challenge.

An emergency navy board was held last month to discuss the crisis, Sky News understands.

Seeking ways to reverse the decline, navy chiefs are considering options to accelerate recruits into training, including potentially inviting some forward on to initial courses before they have passed all their security checks, one source said.

"Previously, the navy has used this for one or two [recruits] - not the hundreds they need now," the source said.

"It's risky!"

In the past, such a move was only for a limited period in exceptional circumstances before security checks were finalised.

'Perfect storm' of negative factors

The recruitment woes are thought to have been triggered over the past 18 months by what the defence sources described as a "perfect storm" of negative factors, including:

• A shortage of up to 35% of recruitment staff in some areas of the UK as navy reservists who fill the role have quit "in droves" because of concerns about job security amid a plan to bring in a new recruitment scheme

• Alleged problems with internal efforts to use data analytics to help with recruitment after the expiry of a contract provided by a private consultancy that had worked well

• A wider failure by the government to ensure armed forces pay keeps up with inflation, making the offer to join the navy, army, and RAF less competitive

• An increasing number of sailors quitting the service. Poor retention has put more pressure on the need to recruit because "outflow" is outstripping "inflow".

"The Royal Navy is witnessing the general collapse of recruitment," the defence source said, speaking on condition of anonymity to discuss the topic frankly.

"In some areas, the Royal Navy teams tasked with recruitment have shortages of up to 35% in their workforce - for instance in Greater London, one of the biggest recruitment areas. This is making it difficult to service all applications in an efficient manner."

The source said: "As the smallest service - workforce wise, with some truly unique trades, connected mainly to submarines - failure in recruitment will have strategic implications at some point in the near future."

Recruitment service 'a mess'

Gaps in recruitment teams are also being experienced in Scotland - a key recruiting ground for submariners who are vital to operate the UK's four nuclear-armed submarines.

These boats deliver the nuclear deterrent - a cornerstone of UK security - with one submarine always at sea 24 hours a day, 365 days a year.

"It's a mess," a second defence source said, also speaking anonymously. "An exceptional recruitment service has been driven to the wall. They need to get a grip of it really quickly."

Admiral Sir Ben Key, the First Sea Lord, took the unusual step last month of admitting in a magazine interview that the Submarine Service was not "awash with people".

He also said the navy was in a "war for talent" as it sought to regrow its ranks after decades of cuts.

Recruitment figures 'frankly desperate'

Official Ministry of Defence data, released last month, showed all three services were struggling with recruitment, but the navy - with a full-time force of just over 29,000 personnel - performed the worst.

Intake in the 12 months to March 2023 plunged 22.1% for the Royal Navy and the Royal Marines compared with a year earlier. For the army, it was down 14.6% year-on-year, and it dropped 16.6% for the Royal Air Force.

Sky News has separately seen unofficial figures that paint an even grimmer picture for both enlisted sailors, who start basic training at HMS Raleigh, in Cornwall, and trainee officers, who are put through their paces at the Britannia Royal Navy College in Dartmouth.

In May, Raleigh saw a mere 109 recruits out of a capacity of 375, with only 10 recruits showing up one week, from a maximum weekly capacity of 75, according to the first source.

A year earlier, the weekly average intake at Raleigh had been about 60 recruits, the source said.

For officers, they can join at three intervals a year - in January, May, and September.

Read more:
Navy boss reveals fears over staffing of UK's nuclear deterrent
Navy's experimental ship carries out first trial of quantum navigation system
Why spectre of British military becoming a 'hollow force' is now a reality

Uncertainty across navy, army, and RAF

This May's intake saw a mere 55 officers signing up at Dartmouth out of a capacity of 175. The course ended up being bulked up by recruits who had failed in the previous term and some international students.

"It's frankly desperate," said a third defence source.

The exodus of recruiters is from a workforce called the Naval Careers Service, which typically comprises specialists who work full-time as reservists on short-term contracts.

They perform the crucial task of helping potential candidates navigate the recruitment process, which includes aptitude, fitness and medical tests as well as security checks.

But recruitment teams have been experiencing a period of uncertainty as the navy, army and RAF prepare to evolve their respective operations into a planned new scheme called the Armed Forces Recruitment Programme - a move that has been beset by delays.

"This programme and its changing timelines is really disruptive for the Naval Careers Service, they have no job security or understanding of where their future lies," the first source said.

"They are therefore leaving in droves, this means the Royal Navy doesn't have sufficient people to process the applications they're getting."

In a bid to fill vacancies in recruitment, navy chiefs are rushing in dozens of regular sailors, but they will need specialist training before they will be fully effective, sources said.

"Ultimately you're robbing the frontline to support backline operations, not the best idea," the third source said.

As well as the impact of a shortage of specialists, navy recruitment has been affected by a change in the way the service uses analytical tools, the sources said.

A management consultancy firm had performed this data and analytics task to assist with better understanding the recruitment picture, but navy chiefs last year brought it in-house after the contract expired.

"This has failed to deliver any analytics after a year of trying - mainly because they don't have the required skill set", the first source said.

"So, the organisation isn't able to understand what is going on and how to respond."

A Royal Navy source rejected this claim, saying the data tools have a high level of accuracy.

In the 'eye of the storm'

Away from these navy-specific issues, the military is simultaneously having to deal with the impact of a delay in the announcement of this year's pay settlement, which should have been agreed before the start of the financial year.

Expectations are - yet again - for a below-inflation pay rise, which equates to a real-terms pay cut and makes a career in the navy, army, or RAF less attractive, defence sources said.

This is a factor prompting more serving sailors to leave, making the need for a healthy recruitment stream all the more urgent.

"We're in the eye of the storm," one of the sources said.

The sources said they feared the navy - under pressure - might rush to bring people on to their books regardless of what trade they want to join, from warfare ratings and aviators to chefs and logisticians.

"My greatest concern is that we just go for the 'numbers' and not specific roles and branches," the first source said.

"This will make our statistics look better in the near future - and stop awkward questions. Yet it will create gaps in key areas like submariners and engineers - where we struggle to recruit."

Responding to the allegations about recruitment, a Royal Navy spokesperson said: "The Royal Navy has enough trained personnel to meet all of its operational commitments, and it is untrue to say there is a collapse in recruitment.

"We are experiencing the same challenges as every employer in the UK and are competing for people against a national shortage. Recruitment is one of our top priorities, and we are working across the navy to continue to deliver success: including the recent launch of our new Royal Marines recruitment campaign."

Former navy officers expressed concern. They said recruitment difficulties were a global trend among navies - with young people less willing to listen to authority, work in a hierarchical environment and - particularly in the case of submariners - be disconnected from technology and the internet for long periods of time.

"I'm really worried because I think it takes such a long time to fix," said former commander Tom Sharpe. "There is no easy fix, otherwise it would probably have been fixed by now."