How to escape a sinking submarine

Submarines are arguably among the most complex naval vessels to operate, and when accidents happen, the dangers are more acute than on any other platform. Alexander Love learns about the safety systems in place and checks out the simulators that help sailors prepare for accidents and emergencies.

Submarines face more operational hazards than other naval vessels, with crews working in enclosed environments where space is noticeably restricted. Should an emergency happen, and submariners need to escape when submerged, options are far more limited hundreds of metres underwater than for ships operating up at the surface.

The recent sinking of an Indonesian Navy submarine was a tragic reminder of the dangers for submarine crews. All 53 crew members died on the KRI Nanggala when the vessel sank in the Bali Sea. The cause of the incident is still being investigated, but the numerous possibilities – from mechanical failure to being hit by an underwater wave – highlight just how many risks there are for submariners.

Should a submarine get into trouble underwater and the crew are able to react, there are potential escape measures available in the right set of circumstances. One of these involves deploying a submarine rescue vehicle, which docks with a submarine’s hatch to allow crews to board and then travel to safety. However, it is not always possible for a submarine rescue vehicle to reach a stricken vessel. For such incidents, another option is available to help increase submariners’ survival chances.

Survival suit

Submarine Escape Immersion Equipment (SEIE) are full-body suits that effectively function as an individual life raft and are used by navies around the world. The solution was originally designed by British company RFD Beaufort as far back as the 1950s, and it has undergone several upgrades and refinements in the subsequent decades.

SEIE can be safely deployed at maximum depths of 600ft and push submariners to the surface at speeds of more than two metres a second. Up to eight crew members an hour can escape the vessel wearing SEIE. The suit has been designed to keep submariners dry and its insulation protects against the risk of hypothermia from the surrounding waters. It also helps to stop decompression sickness and prevents personnel from feeling the effects of extreme changes in body temperature caused by moving from the warm conditions on board the submarine to the cold, murky waters outside.

Crew members can wear the suits for up to 24 hours, which should be enough time for them to be rescued. Each SEIE unit also contains emergency supplies of water and rations, heat packs and signalling equipment such as whistles. The SEIE’s distinctive shade of orange ensures visibility on the surface for search-and-rescue vessels.

Yet submariners need to know how to deploy the SEIE safely and training is essential for this.

Training facilities

The UK Royal Navy has a highly respected international record when it comes to submarine safety. Given the specific environments where submarines operate, personnel require a specialist training facility to simulate the underwater depths and the potential operational scenarios.

Recently, the Royal Navy opened a new dedicated state-of-the-art facility at HM Naval Base Clyde at Faslane in Scotland to ensure that naval personnel receive the most up-to-date safety training for operating on submarines.

The Submarine Escape, Rescue, Abandonment and Survival (SMERAS) building is the result of a three-year design and construction process. The UK Government’s Defence Infrastructure Organisation (DIO) oversaw the development of the £34m facility, working alongside contractor Kier Graham Defence throughout construction.

Similar drills and exercises previously took place at the Submarine Escape Training Tank (SETT) at Fort Blockhouse in Gosport, Hampshire. The fact that SETT originally opened in 1953 gives a clear indication of just how long the Royal Navy has been training personnel to escape from submarines. During the Gosport site’s 66 years of service, the 100ft water tank was used for ascent training on more than 150,000 occasions. At the facility’s busiest period in the 1960s and 1970s, approximately 4,500 submariners performed this vital training there every year.

At the new SMERAS building in Scotland, Royal Navy personnel will undergo training within a controlled environment. This training will mean that by the time that personnel set foot on a submarine, they will be prepared for what could await them.

// SMERAS features an accurate replica of a submarine hatch and ladder for training personnel. Credit: Crown Copyright/MOD 2020.

Vital experience

The SMERAS facility’s training pool can simulate waves, winds and rain, as well as various sea states. The site also features an accurate replica of a naval submarine’s hatch and a ladder that submariners can climb wearing full SEIE to gain vital experience in how it feels to move around the suit and become familiar with the physical constraints. Personnel can also learn the correct techniques to deploy when using SEIE underwater as they ascend to the surface and then board a life raft.

“The SMERAS Training Facility is a fantastic new and world-leading escape and surface abandonment capability that enhances the training benefit for Royal Navy submariners,” said Royal Navy commander D McClement, fleet operational sea training (submarines) at HMNB Clyde, when the facility was completed in November 2020.

“The facility fulfils a significant gap for the Royal Navy in delivering realistic experiential training for surface abandonment in addition to submarine escape.

“The Royal Navy’s reputation for submarine escape training has been significantly enhanced by this impressive capability that combines both escape and surface abandonment training.”

SMERAS is a key element in the development of HM Naval Base Clyde.

Other organisations involved in building the site include the MoD’s Defence Equipment & Support and Babcock Marine Training, which played a crucial role in delivering training equipment for the building. Babcock was involved in the design of training solutions such as specialist submarine hardware and training courseware. The company can also provide training instructors if required by the Royal Navy.

“The facility provides class-specific high-fidelity escape towers and escape compartments, a training pool capable of replicating the environmental conditions that submarine escapes may need to be carried out in and supporting classrooms, offices, workshops, plant rooms and changing areas,” commented John Thomson, Royal Navy Command assistant head of infrastructure, when the facility opened.

“SMERAS is a key element in the development of HM Naval Base Clyde as the Royal Navy Submarine Centre of Specialisation and base port for all UK submarines.”

DIO has announced that it will invest £1.6bn in the further development of HMNB Clyde. The aim is to make it a centre of excellence for submariners’ training.

// Main image: At the SMERAS training facility, sailors can gain experience wearing SEIE in the training pool. Credit: Crown Copyright/MOD 2020