On 12 February 2018, a second world war bomb was found in the King George V Dock, near City Airport. Lt Cdr Sean Heaton RN writes about his job as a diver in the Royal Navy, his team's efforts to diffuse this bomb — and the many others found in London.
"It's like swimming in Guinness"
Being dragged out of bed at any time of night is part of the job. The Royal Navy's Southern Diving Group, which I command, has a team of divers ready to go, around the clock, at just 10 minutes' notice.
When a second world war bomb was found in King George V Dock — just 150m from the terminal building at London City Airport — flights were cancelled and homes were evacuated to keep people safe. Our priority was to minimise the danger and disruption to Londoners as much as possible.
Clearance Diving Units in the Royal Navy work to protect the waters around the UK, from the Channel Islands to Shetland. We're also trained to support ships on operations around the globe, whether that means diving in sub-zero temperatures of the Antarctic or in 50-degree heat in the Middle East. But the Thames is a world of its own.
Once you're at the bottom of the Thames, visibility is close to zero. You can barely see further than half a metre in front of your face, and the slightest movement kicks up the soft sediment on the bottom and envelopes you in a cloud of mud. It's like swimming in Guinness, and it's a challenge to keep your head and not get disorientated.
Diving is not our job; it's just the commute. The real work starts once we're underwater and in contact with the bomb. Because visibility is so poor, we’re trained to memorise key measurements like the length of our arms and fingers and the span of our chest. That way, we can use what's in front of us to get an idea of the size of the bomb and relay accurate estimates to the surface.
"One of the biggest dangers is the unknown"
To minimise the number of people at risk, we often dive alone. Our only communication with the surface is a single line of thin rope, which we can pull a specific number of times to relay a specific message. Although we have the equipment to communicate electronically from seabed to surface, we can't risk the electronic signals triggering an explosive device.
One of the biggest dangers is the unknown. Why didn't this bomb go bang 70 years ago like it should have? What might set it off now? As soon as we could, we towed the bomb out of the dock and into the middle of the Thames, to reduce the impact on the airport and people's homes should the worst happen. That allowed the police to lift the cordon and let Londoners' lives get back to normal.
One of the biggest dangers is the unknown. Why didn't this bomb go bang 70 years ago like it should have?
By this time, we had been working on the operation for 15 hours straight. Now that we were in the centre of the Thames, we brought the bomb really close to the boat so we could keep it under control. With the help of the Port of London Authority and the Marine Policing Unit, we towed the bomb along the Thames, far out of London and out to the Essex coast.
"The adrenalin rush turns to relief"
Then we detonated it. The weight of the sea water dampened the worst of the blast, but the photos show the impact of the explosion and just how destructive the bomb could have been in the middle of London. Once the bomb is disposed of, the adrenalin rush turns to relief. You feel good after a successful operation, but just 12 hours later we were on the road again responding to the next explosive device.
It can be tiring and relentless — my team gets called out every 18 hours on average — but my experiences as a Royal Navy Diver have far exceeded all my expectations. I used to watch divers on TV as a child and hoped I could one day do an adventurous job like them. After 31 years in the Royal Navy, I still get a thrill from diving and protecting the public under pressure.
Armed Forces Day 2018 takes place on Saturday 30 June.