A century on from some of the world's first successful submarine rescues, dangers still abound despite massive advances in technology and international co-operation. In this timeline, Dr. Gareth Evans explores how far we've co me and how far there still is to go.

The Defence Academy of the United Kingdom delivers higher education for members of the Armed Forces and government representatives. Visiting its campus in Shrivenham, southwest Oxfordshire, on a brisk winter’s day leaves no doubt of its military associations. Once admitted through a secure entrance, acres of low-lying buildings jostle behind high wire fences, and at least half the personnel walking between them wear camouflage.

What might be more surprising is that the site also hosts a branch of Cranfield University, 70 miles from its main campus. Cranfield Defence and Security (CDS) delivers defence and security education, research and consultancy, and a significant part of this is the Centre for Defence Chemistry (CDC), which has been working on propellants, explosives and pyrotechnic research for decades. CDC works on all aspects of defence manufacturing, vulnerability, combustion, and life assessment of energetic materials, or explosives as they’re more commonly known. 

The icy waters of Gareloch in Argyll and Bute, Scotland, saw one of the world’s first successful submarine rescues in January 1917 when HMS K13 sank during sea trials, with an 80-strong assorted complement of crew, Royal Navy dignitaries and civilians aboard.

By 22.00hrs on the night of the 29^th – roughly ten hours after the K13 went down, the first rescue vessel arrived, and divers were sent down at daybreak, who managed to establish communication with the survivors using Morse code tapped out on the hull. Later that afternoon, an airline was attached to the vessel, enabling the ballast tanks to be blown and, by noon on the 31^st, with the aid of a hawser, the K13’s bows were brought above the surface, and supported by a barge on either side. A hole was then cut in her, and by 22.00hrs – 57 hours after she sank – the last of the 48 survivors had been safely rescued.

In 2017, a ceremony was held at Faslane Cemetery in Garelochhead to mark the centenary.

“Another part of increasing our skills was giving young students coming in meaningful projects, and keeping them interested.”

In the early days of submarines, rescuing the crew aboard a stricken vessel tended to focus more on self-escape than external assistance, with a number of systems and devices being developed to help, based on the kind of breathing apparatus then available for use in coal mines.

One of the earliest types was the Davis Submerged Escape Apparatus (DSEA), which was invented by Sir Robert Davis in 1910, and adopted 19 years later by the Royal Navy, after a period of further development. DSEAs remained in service until a comprehensive 1946 Royal Navy inquiry found that there was no difference in the survival rates between those who escaped stricken subs with or without them. The DSEA, arguably the first re-breather escape system to be mass produced, was subsequently dropped in favour of the so-called ‘blow and go’ technique.

“Another part of increasing our skills was giving young students coming in meaningful projects, and keeping them interested.”

On the morning of the 23^rd of May 1939, the Sargo-class submarine USS Squalus – the newest in the fleet – began a routine test dive off the coast of Portsmouth, New Hampshire, that was ultimately to turn into the first successful deep-water rescue in history.

Within minutes, she began flooding uncontrollably as the engine room filled with water through the main induction valve, and sank in over 240 feet of water. Twenty-six of the crew, located aft, drowned immediately; the remaining 33, in the forward section, were located alive some hours later by her sister-sub, the Sculpin.

The next day, US Navy divers led by Charles ‘Swede’ Momsen – inventor of the Momsen Lung escape breathing device – successfully used a rescue chamber, also largely of his own devising, to free the trapped submariners. It took four separate trips, with the last of the survivors reaching the surface a little after  midnight on the 25^th.

“Another part of increasing our skills was giving young students coming in meaningful projects, and keeping them interested.”

Test dives were to be at the centre of yet another incident, and one which still retains the dubious distinction of being the single highest death toll in submarine history.

On the 10^th of April, the USS Thresher was engaged in a series of post-overhaul tests some 220 miles off the coast of Boston, Massachusetts, accompanied by the submarine rescue ship Skylark. As Thresher began to dive, travelling in circles beneath Skylark to maintain communications as the submarine moved towards her deep-diving test depth, the rescue vessel picked up garbled messages reporting “minor difficulties” and then heard no more.

An extensive underwater search later revealed the wreckage of the hull, broken into six sections and lying in 8,400 feet of water. The first nuclear submarine lost at sea, the sinking of the Thresher claimed the lives of all 129 aboard, but their deaths were to prove a defining moment for the US Navy that led to the new and rigorous submarine safety initiative, SUBSAFE.

“Another part of increasing our skills was giving young students coming in meaningful projects, and keeping them interested.”

The loss of the Thresher also kick-started the development of deep submergence rescue vehicles (DSRVs), with the US Navy instigating the Deep Submergence Systems Project in 1964. By the early 1970s, it had yielded two advanced and highly capable submersibles named Mystic and Avalon, which attained operational status in 1977 after extensive sea trials and formed the backbone of the US Navy’s submarine rescue capability through to 2008.

Today, the DSRV has become a familiar and essential asset for submarine operators around the globe – perhaps a fitting legacy for those 129 lost in the dark waters off Boston in 1963.

“Another part of increasing our skills was giving young students coming in meaningful projects, and keeping them interested.”

The sinking of the Kursk during Russia’s first major maritime exercise for over a decade came as an abrupt wake-up call to the Russian Navy, and a timely reminder to the rest of the 40 or so nations who operate submarines of just how badly things can go wrong.

On the 12^th of  August 2000, two explosions, two minutes and 15 seconds apart, sank the Oscar-class submarine in the Barents Sea. Despite being registered by nearby ships, the Russian Navy remained unaware that the sub was in trouble for some hours and vital time was lost both in mounting a search and locating the downed vessel. Over the next four days, attempts were made to reach the Kursk using submersibles and diving bells, while overly-optimistic official ‘misinformation’ was circulated at home and abroad about the rescue operation.

On day five, having previously refused international offers of help, President Putin capitulated and accepted the assistance of Britain and Norway. However, by the time Norwegian divers reached where the survivors were thought to be located, it was already too late.

“Another part of increasing our skills was giving young students coming in meaningful projects, and keeping them interested.”

There were many developments in the wake of the Kursk tragedy amongst the submarine-operating countries of the world, but arguably none more globally important than the establishment in 2003 of ISMERLO – the International Submarine Escape and Rescue Liaison Office. Initially set up by NATO and the Submarine Escape and Rescue Working Group  and housed in Norfolk, USA, its permanent HQ is now at Northwood UK.

Consisting of a multi-national expert team of submarine escape and rescue specialists, ISMERLO’s goal is to help prevent accidents, establish agreed procedures to form the basis of an international standard for peacetime submarine rescue, and facilitate the rapid call-out of appropriate rescue resources as required. The organisation has now become an intrinsic part of global submarine rescue.

“Another part of increasing our skills was giving young students coming in meaningful projects, and keeping them interested.”

Five years on from the Kursk disaster, which saw Moscow heavily criticised for refusing foreign help, lessons had obviously been learnt.

On the 4^th of August, a Russian Priz AS-28 mini-submarine became caught up in sub-sea cables off the coast of the Kamchatka peninsula. Held fast in 190m of water and unable to surface, she issued a mayday, and this time assistance was swiftly sought from the UK, US and Japan. Three days after the Priz was first entangled, and with concern growing over how much oxygen was left, a British-owned-and-operated rescue submarine arrived and successfully freed the Russian sub, saving all seven on board.

“Another part of increasing our skills was giving young students coming in meaningful projects, and keeping them interested.”

The disappearance of the San Juan at the end of 2017 stands as a stark reminder that despite a century of advances in rescue technologies, and massive multi-national cooperation, submarines do still sink and lives will be lost.

The Argentine vessel was last heard from on 15^th November, while on patrol in the South Atlantic, and her disappearance sparked a truly international search and rescue operation involving more than a dozen countries, which ran for a fortnight. Ultimately, however, it was abandoned after failing to locate the sub, which in any case only carried enough oxygen for seven to ten days when submerged, and all 44 on board, including Argentina’s first woman submarine officer, were declared lost.

Seismic listening posts on Ascension Island and Crozet Islands detected an ‘acoustic anomaly’ near to the sub’s last known position a few hours after she last made contact. This was close to the edge of the continental shelf, leading to some speculation that the sound might have been the San Juan imploding under pressure.

“Another part of increasing our skills was giving young students coming in meaningful projects, and keeping them interested.”