It was a freezing, overcast day when I entered the Royal Navy’s Defence Diving School on Horsea Island.
Wind was whipping over the grey-brown surface of the training lake, which plays home to one of the UK’s most elite units – the Fleet Diving Squadron.
I was there to meet new recruits preparing to tackle the notoriously gruelling training course every diver needs to pass.
As I arrive, two of the latest intake – Fraser Malek and Andrew Gibson – are already practising their drills, stripping down to their boxer shorts as quickly as possible and strapping themselves into the dry suits. It’s one of the very first exercises all divers tackle.
Known as ‘awkward’, it simulates the sudden call-up any operator can face when out on deployment.
The pair have just two minutes to strip from their clothes and into their diving equipment. The sense of urgency is tangible as they check one another over to make sure their dry suits are all zipped up and secure.
‘You never feel like you’ve got enough time to do it,’ 26-year-old Andrew tells me, breathlessly.
The pair are already experienced in what it takes to pass out of military training; Andrew was a former Lance Corporal in the Royal Marines while Fraser has been in the navy for five years.
But they tell me nothing could have prepared them for the harsh realities of attempting one of the Royal Navy’s toughest courses.
‘I joined the navy to travel the world but honestly, I’d never thought about becoming a navy diver,’ 22-year-old AB Malek adds.
‘It’s only when I saw them while on deployment that I thought about it. There was something different about the way they acted.
‘It inspired me. It’s now this or nothing. I absolutely want this. I’m either going to go for this or leave the navy.’
The training simply to become a diver is punishing.
Recruits need to endure a relentless regime of exercises which push them to their physical and mental limits, from hours of non-stop swimming and training in the 1,000m-long training lake, to completing a 10km ‘warm-up’ which can see recruits being forced to crawl on their bellies through energy-sapping mud – all while wearing their cumbersome dry suits.
During the 24-week course, they will also tackle the nightmarish Live-in Week.
Recruits spend an entire week living on the island, where instructors will deprive them of sleep and force them to undertake exercises which push many recruits to breaking point.
The process is similar to the US Navy SEALs’ ‘Hell Week’ – it’s designed to show who has the grit to push through the pain and become a Royal Navy diver.
‘At the end of Live-in Week you know that they have got the determination and that they are the right person we want,’ says Leading Diver Kev McBride.
As Lieutenant Commander Mick Beale adds, the training is fundamental in preparing the divers for the harsh realities of combat.
‘In times of conflict you could be working incredibly long hours,’ he tells me.
‘It doesn’t matter what time it is, if you’re diving you dive.’
It’s not just about being physically fit though.
Divers have to have the mental robustness to deal calmly with deadly explosives, which, if they make one wrong move, could kill them in the blink of an eye.
If trainees are successful and graduate from the course, they will become mine clearance divers, based either on shore or on board a mine countermeasures (MCM) vessel.
The main role will be to identify mines and other explosives, whether in shallow water or attached to the hull of a ship, and get rid of them, which might mean blowing them up.
As well as modern technology, they could be called on to dispose of old mines from the Second World War dragged up in a trawler’s nets.
They have also been trained to use hydraulic and pneumatic tools and shoot video, while working at a maximum depth of 60 metres.
Leading Diver Luke Palmer, 26, who was born in Portsmouth, completed the course in 2010. Reflecting on it, he said: ‘The training is just honking. It’s something that, psychologically, you can’t prepare for. It’s one of the hardest things I’ve ever done.’
But he says he has no regrets.
He is part of Fleet Diving Unit 2 which specialises in shallow water operations.
In 2013 he was deployed on exercise in Albania where he had to recce a beach to make sure it was clear for a raiding party to land on it.
‘It’s a real rush of adrenaline,’ he tells me.
‘You swim out with just a pistol and a knife for two and a half hours. There are Marines trying to spot you while you’re on the beach, and the last thing you want to do is mess up.’
Any British national aged between 18 to 33 can apply to join the service. They must first complete a pre-entry diving course and pass the diver physical fitness test.
Following basic training at HMS Raleigh, there is a special medical examination and a one-week selection test at Horsea Island that must be passed.
Those keen to find out more can call 08456 075555 or visit royalnavy.mod.uk/careers