What lies beneath: the German sub sunk off the coast of Fujairah

U-533 was hit in 1943 by an RAF squadron from Sharjah

Deep sea diver Simon Nadim at his XR Hub Dive Centre in Fujairah. Mr Nadim has completed dozens of dives to the wreck. Antonie Robertson / The National

Related: Missing diver's gas tank found near submarine wreck off UAE coast

On October 16, 1943, a British Royal Air Force bomber took off from Sharjah on a routine patrol of the coast.

The Bleinheim Mark V veered east, across the Hajjar Mountains and out into the Gulf of Oman. But this day was going to be anything but routine.

The crew, piloted by Lewis Chapman, soon spotted Nazi submarine U-533 about 46 kilometres off the coast of Fujairah.

It dropped four depth charges. The U-boat made a desperate but futile attempt to dive. Of the crew of 53 sailors, only one survived. Gunther Schmidt was taken to Sharjah where he remained as a prisoner of war until 1945, while Chapman was killed a year later as a passenger on another flight.

"It was the only German submarine that we know of to be sunk in the Gulf of Oman during the Second World War," said Dubai resident Ali Iqbal, who co-wrote a paper on the submarine with historian, Peter Hellyer, for Tribulus, the journal of the Emirates Natural History Group. It was part of the Monsun Gruppe (Monsoon Group) wolfpack targeting Allied ships in the Indian Ocean.

It was the only German submarine that we know of to be sunk in the Gulf of Oman during the Second World War

The story of the U-boat was forgotten for decades: the details of its sinking buried in archives, while the wreck became a haven for fish 110 metres down on the seabed. But divers based out of Dubai discovered the wreck in the late 2000s and it has now become an increasingly popular dive site.

Simon Nadim, a Lebanese instructor who operates out of Fujairah, has completed dozens of dives to U-533.

He recently recovered a discarded gas tank of a Jordanian diver who disappeared on April 15 last year while exploring the wreck.

He said the submarine is still in pristine condition on the sandy seabed. Video footage taken during his dives shows the U-boat emerging from the blue gloom, with its cannon and conning tower — a type of turret used to command the vessel while on the surface — still intact.

“You can see damage at the stern around the propeller,” said Mr Nadim, 40, who runs the XR Hub Diving Centre.

“It doesn’t seem to have been a clear hit and it is all in one piece. And it is crowded with marine life.”

The interest in the German wreck has coincided with an increased awareness of the effect that the Second World War had on the region.

Modern-day UAE was not an active theatre of war but the RAF at Sharjah played an important role in patrolling the coast from U-boats trying to disrupt oil tankers for the Allied war effort.

Divers have not been able to penetrate the interior of the sub, which is also a graveyard for dozens of sailors. “It is a moment frozen in time,” said Mr Nadim.

“It reminds you of the history and also to remember the people who fought, for not a good cause, but they were far away from their country. It feels like a time machine.”

Through his dives and the work of others, divers from across the world have now heard about the wreck. “The submarine is many divers’ ultimate dream. A lot of people consider it a big achievement because of the technicality of it.”

The depth is compounded by the strong currents and web of fishing lines that are snagged around the area. A Jordanian diver became entangled in one of these lines a year ago and his body has never been found.

Safety is paramount for Mr Nadim: divers are highly trained, reserve divers wait on-board with extra tanks in case of an emergency and divers carry reserve amounts of gas with them. They use lines to reach the submarine, battery-powered scooters to shuttle around and then ascend with breaks to avoid decompression sickness, which he compares to shaking a can of Pepsi and opening it.

“This diving is a type of science,” said Mr Nadim. “It is like going to the moon. So we need to follow the rules.”