Submarine Rescue Systems

Providing support for the subsea Defence industry: SRVs, ROVs & UUVs

Forum Energy Technologies is a world-leading designer and manufacturer of submarine rescue systems and equipment. FET has reliably supported military organizations and naval forces for more than 45 years.

Encompassing two of the leading brands in the design and build of remote intervention vehicles – Perry Slingsby Systems and Sub-Atlantic, Forum has supplied over 800 manned and unmanned underwater vehicles.

Building upon a wealth of experience, and utilizing the latest technologies available, todays submarine rescue vehicles (SRV’s) operate without tether utilizing battery power and are capable of diving in depths over 600 metres and rescuing 17 submariners per dive.

Previously delivered systems include NSRS (NATO Submarine Rescue System) which entered service in 2008 and “remains the benchmark” according to many of her team – NSRS is on constant standby for rescue operation in any part of the world and is specifically packaged for rapid deployment by air transport with all other surface elements of NSRS.

The latest SRV system was completed in November 2020 for a foreign navy in the Asia-Pacific region and was built to the latest Lloyds design codes to facilitate full class certification. The system was also supplied with a Launch & Recovery System and a complete training & aftersales support package as well as an ROV System, Simulator, ELSS Pod Skid & Mating Target.

Forum also has a long history of supplying ROV’s to the global military market including Intervention ROV’s which are designed to be deployed rapidly to minimize the time taken until first Intervention – these incorporate the latest technologies to facilitate advanced ‘AUTO’ functionalities.

Forum’s operational base in Kirkbymoorside, Yorkshire (UK) operates Europe’s most advanced subsea manufacturing and vehicle testing facility. Secure and confidential, it boasts one of the world’s largest horizontal pressure test tanks for hyperbaric pressure testing, and a deep tank for full ROV and rescue submersible systems certification.

With a proven track record in the defense market, we are proud to deliver cutting-edge technologies which are at the forefront of the subsea industry and remain the systems of choice by many of the world’s military and naval forces.

Whatever the mission, Forum Subsea Vehicles has the solution.

Rescue Vehicle (SRV)

The SRV is a manned submersible and was developed from previous rescue vehicles. It is operated by a three-man crew and capable of rescuing 18 crew.


  • 10m long, 28,000kg
  • Q1N Submarine steel, single-piece hull
  • Operating at depths above 600 meters
  • Can mate with distressed submarine at angles of up to 60 degrees
  • Utilizes the latest Sensor and Battery technologies available

Much of the technology developed by Perry Slingsby Systems for the oil and gas sector has been further developed for applications for the defense market, such as:

  • Intervention Class ROV (IROV) for locating and surveying distressed submarines (DISSUB) and delivering emergency life-support stores (ELSS)
  • Deck located control rooms
  • Launch and recovery systems
  • Manipulator arms for torpedo recovery
  • Suction foot
LR Class Command Module
LR11 Harbor Trials
LR Manipulator


The Forum Perry® Emergency Life Support Stores (ELSS) containers are pressure-tight pods used by navies as part of a distressed submarine rescue system. In the event that a submarine becomes stranded on the seabed, ELSS containers are posted into the submarine’s hatches to deliver life-preserving stores to the crew until a full rescue can be mounted.

The ELSS pod is designed to be nominally 10 kg negatively buoyant in seawater, which enables it to be delivered to the Submarine by a swimmer, an Atmospheric Diving Suit (ADS), a Remotely Operated Vehicle (ROV) or the Rescue Submersible itself.

Each ELSS container comprises a cylindrical pressure vessel with a removable end cap fitted with a lifting handle. The payload of the container can be varied using a combination of ballast weights, which keep the weight in water of the container constant.

The cylindrical pressure vessel is manufactured from aluminum and coated with yellow Xylan, which is both tough and resilient to impact during deck handling and deployment.

The removable end cap is manufactured from aluminum alloy and is fitted with a stainless-steel lifting handle. A pressure equalizing valve ensures that the cylinder is not under or over-pressurized before being opened.

The ELSS pod is compliant with ANEP-85 “Material Interoperability Requirements For Submarine Escape And Rescue.”


The FET Perry® Emergency Life Support Stores (ELSS) container Capture System is individually designed to suit the escape tower / escape hatches of navy submarines throughout the world.

The Capture System allows the safe receipt of ELSS pods by a distressed submarine (DISSUB). In the event that a submarine becomes stranded on the seabed, ELSS containers are posted into the submarine’s hatches, by a diver or ROV (remotely operated vehicle) to deliver life-preserving stores to the crew until a full rescue can be mounted.

The Capture System is comprised of four main components. The Support Ring Assembly, Capture Net and Rope Anchor Brackets. Each system is also supplied with two off Rope Bags for easy storage.

The ELSS Pod Capture System has been designed in accordance with ANEP/MNEP-85. A system load test is performed, and the system is certified to allow the receipt of a fully flooded ELSS pod. The support ring assembly and capture net frame are made from marine-grade stainless steel.


SRV Mating Target

Regular submarine rescue exercises are important to ensure personnel and equipment are ready to respond in the event of an incident. Forum’s submarine rescue system mating target is designed as a training aid for submersible operators.

  • Replicating the submarine’s escape hatch, the target is designed to be used at depths of up to 600 metres, and in currents up to 2.5 knots, with safe deployment up to a Sea State 4.
  • It weighs approximately 6,500 kg and has integrated lifting features allowing it to be deployed and retrieved from a ship-mounted crane.
  • Under these operating conditions, a soft and hard seal can be created between the SRV’s Dry Mating Skirt (DMS) and the Mating Target Disc.
  • The Target Disk angle is adjustable from 0° horizontal to 40°.
  • The Mating Target can be disassembled and stored in a standard 20ft shipping container with the leg extensions and lifting beams removed.
  • Fully pressure tested and load tested.
  • The Target Disk is painted with the ‘bullseye’ dimensions defined in NATO STANAG 1297 “Requirements for a NATO Common Rescue Seat” providing the SRV pilot enhanced visibility when mating.

Sticky Foot

  • The 300 diameter suction foot can hold an ROV to smooth surfaces such as ship hulls & submarines
  • The attachment arm is a three-function manipulator consisting of shoulder pitch, jaw and extend

Torpedo Detection & Recovery Grab

  • Deployed by crane, positioned and secured by ROV
  • Controlled contact pressure on torpedo
  • Incorporates torque limiter and back-up release handle
  • Flags indicate clamp status
  • Torpedo recovered to surface by slings and crane

Ventilation and Depressurization System (VDS) Connection Tool

  • Tool that allows VDS systems to be installed by an ROV (instead of a diver)
  • Bespoke tools can be supplied to fit any VDS system to any submarine

VMAX Simulation Solutions

Forum’s VMAX Product Line offers a range of applications that provide 3D simulation of subsea operations in the commercial offshore and defense sectors. VMAX uses a rigid body physics engine to provide realistic modeling of subsea vehicles, equipment, and structures and the ability to apply a variety of environmental parameters to the simulated operation, or scenarios. It has been successfully used by militaries and navies for many years to run simulations of complex situations, such as pod posting.

To learn more about VMAX, click here.