Royal Navy submariner reveals what really happens when you spend 200 days underwater and what the biggest danger is when you finally come up for air

On August 29, 2023, as HMS Vengeance slipped beneath the waves, her crew of 130 prepared for a marathon patrol in a classified location. 

As part of Britain’s continuous nuclear deterrent the Vanguard Class nuclear submarines have a single mission, to await a call that nobody onboard ever wants to receive. Within 15 minutes of taking that call the world will change beyond recognition. The Trident nuclear missiles on board the submarine are able to hit a target 7,000 miles away.  

Earlier this month, after more than 200 days at sea, HMS Vengeance returned Faslane on the River Clyde. Only a handful of those on board will have known where in the world they had been. Though, each of the crew will have received a bonus of £25-a-day – some £5,000 – as recompense for missing Christmas, birthdays, anniversaries and even funerals.  

For that bonus, the crew are unable to contact their families or the outside world. They are also sealed into a 461ft metal tube for more than 4,800 hours, deprived of fresh air and oxygen. 

One Cold War veteran who served on nuclear deterrent boats told MailOnline: ”The guys who are going down for at least seven months, I don’t know how I would have handled that.’

A nuclear submarine can create its own water and oxygen to sustain the life of the crew. 

In theory, the submarine can patrol for years without needing refuelling. The crew, however, are different. They need food which is supplied in great abundance.

It is grilled rather than fried bacon and sausages for breakfast; dishes like Toad in the Hole, to sweet chili chicken and corn beef hash for lunch and a range of curries, fajitas and fish and chips for dinner. 

Phil’s service was as a navigator on the first nuclear submarines in the British fleet at the start of Operation Relentless – the start of the UK’s Continuous at Sea Deterrent

Pete, left, was on diesel electric boats during most of the Cold War, finally breathing continuous fresh air in 2000

Operation Relentless – the UK’s Continuous at Sea Deterrent has seen at least one ‘bomber’ submarine on patrol carrying Britain’s nuclear deterrent since 1969. 

Submarine crews have traditionally earned a ‘knowledge bonus’ while at sea because they have to be able to operate systems in an emergency or identify valves to prevent flooding in all areas of the boat. If the boat was sealed, a crew member would be expected to solve the problem without relying on outside help. 

Before nuclear power, submarines had to regularly surface, to replenish their oxygen supplies or run their diesel engines to recharge their electric batteries. 

At the Royal Navy’s Submarine Museum in Gosport, Hampshire, HMS Alliance is the last surviving WWII-era British submarine. 

However, by the time she was launched she was quickly prepared for the Cold War, undergoing a major refit to make her more silent. 

The UK’s nuclear deterrent is currently being carried by the four Vanguard-class submarines, pictured here HMS Vengeance, the fourth and final boat in the fleet

One of the four nuclear boats is always at sea. One is undergoing refit, while the remaining two are used for training and are available for rapid deployment

In the late 1960s, Philip Luxton and Pete Hobson joined the Royal Navy. 

Mr Luxton spent much of his submarine career on Polaris nuclear submarines. The Resolution-class submarines were the first ‘Bombers’ in the fleet capable of extended periods of patrol. He was part of the first crews involved in Operation Relentless which continues to this day. 

Somewhere in the ocean there is a Vanguard Class submarine at more than 1,000ft moving at three knots. Less than 20 of the crew will ever know where they are or have been. 

His friend, Pete Hobson, joined the Royal Navy in 1965 aged 15. He said he was being trained on the use of sonar when he saw on of these ‘black sleek messengers of death’ slip into Portsmouth when he thought: ‘That’s for me. The hairs on the back of my neck stood up.’ 

However, unlike he was on diesel electric attack boats until the turn of the century. 

Both have spent extended periods away from home, hundreds of feet below the surface – either looking for or trying to avoid hostile vessels.

Phil and Pete bring visitors to the museum around HMS Alliance – a World War II era diesel electric boat which was rapidly reconfigured to operate in the Cold War as a ‘sneaky boat’

On one patrol, Pete, left, was onboard a submarine which caught fire while they were directly below ‘an interesting boat’ which they were having a ‘sneaky’ look at

The two types of submarines have completely different missions and tactics. The bomber will travel to its assigned patrol area and move slowly – possibly down to three knots – creating as little noise as possible so it cannot be observed by electronic or physical surveillance. 

The attack boat – or ‘sneaky boat’ – will be seeking out other submarines and ships to gather intelligence. They are also used to deploy Royal Marine Commandos or members of the Special Boat Service on dangerous secret missions. 

When Mr Luxton was onboard the nuclear deterrent boats in the 1970s, the average patrol was two months. Now it is more than six. 

Speaking to MailOnline, he said: ‘The guys who are going down for at least seven months, I don’t know how I would have handled that. When I was going on patrol for two months, there was always so much going on. 

‘You are either on watch or when you come off watch you are eating, sleeping or watching a movie. 

‘We had plenty of activities, we did. They even had a gym situation with a rowing machine and a running machine down with the torpedos. 

‘There were plenty of things to do. There were competitions. There is Ludo – but in the navy it is Uckers – it is a very vicious game of Ludo as it is very complicated. It can last for hours and is played in teams of two. All sorts of banter goes on with it. It is not the type of thing that you play at Christmas with your kids. 

Life on board a submarine is cramped – even on a modern Vanguard class sub. According to Phil, who has been on patrols for two months, the most serious thing you notice returning to land is the ‘loss of depth perception’ as while on board you can never see more than 30-feet away

According to Phil, during his two-month patrols he earned an extra £1-a-day which could buy six pints when back on shore. Today submariners receive £25, which he says sounds like more money, but it wouldn’t buy six pints

‘These guys doing this seven month patrol, we would do two months. The time does go fairly quickly. You all get on with each other because you’re one big family. 

‘There’s the banter going on between the different sections – the stokers and the seamen. I worked in the Nav Centre and we were always known as Nav Queens. Probably one of the cushiest jobs on board. That’s why we got that nickname, I suppose.

‘The Alliance has only got one deck. The one I was on had three decks and I think the new deterrence is very much the same. They are nearly twice as long and twice as wide. Weight wise, the Polaris was six times the size and the Valliant are 12 times the size. 

‘There is a lot more space on board a modern sub than in the old boats.’ 

Spending extended time at sea on board a submarine can give you ‘nose blindness’ which affects your sense of smell. 

On a nuclear boat, the air is ‘scrubbed’ clean to remove the carbon monoxide. But there is a more serious issue for returning submariners after a long deployment. 

According to Mr Luxton: ‘There is another problem. When you’re in that close confinement, it can affect your distance perception. The maximum you can see is about 30 feet. When you get back you’ve got to be very aware that when you are driving and you get into a car, your distance perception is not right, you’ve got to really get used to it again. That’s the only problem.

‘Only rarely on the patrols I was on would we be at periscope depth and we would never surface. When you are at the top you are very vulnerable. You want to know what is there. They can’t see you so you want to see what’s up there for your own safety. There are no lookouts – because we are down below. 

‘For most of the crew, they will know where Scotland is, and that’s about it.’

He said in the mess, other members of the crew would speculate as to their location, claiming to be able to figure it out. Philip knew the answer but could not reveal the position, laughing inwardly about how wrong some of his comrades were. 

‘I never had a problem and I never saw anybody with a problem with any of the guys I was with. You hear about stories about people “throwing wobblies” and that, but I never came across it at all. 

‘You are there for a purpose. You are watchkeeping and have a job to do. You are working all the time. You carry on Sunday to Saturday. 

Three four-hour shifts to cover the day and two six hour shifts to cover at night. 

‘In the control room at night time we use “black lighting” where everything goes red.

‘There are two reasons. The first is for your eyes to adjust in case you have to surface and need to do a look out and also to give a sense of body clock. 

‘Also, at night, if using a periscope – if unlucky – the light could make its way up the periscope and give your position away.’

Today, the need for constant contact with the outside world is an issue for recruiting people for the Submarine Service. 

‘One of main reasons the young lads do not want to become a submariner is because they don’t have the contact with the outside world on the internet. 

But the next generation submarines will not have a periscope that goes through the hull – instead. 

Mr Luxton: ‘I was on patrol on one of the Polaris submarines when they stopped “the tot”. 

‘We had quite a ceremony on board. We built a coffin and the rum fanny – as we called it – the barrel – that was placed on top and we paraded it through the submarine… it was a sad day.’ 

A Royal Navy spokesperson said: ‘Our continuous at sea deterrent protects us and our NATO Allies every moment of every day.

‘We are immensely grateful to the submariners onboard, and their loved ones, for their commitment and dedication.

‘While we do not comment on patrol lengths, we take safety very seriously and all submarines go through rigorous safety checks before any patrol.’