Environmental Parameters* Operational sea state
In air operating -5 to +45°C
In water operating up to 32°C
Operating humidity range up to 90%
Storage -10 to 60°C
*Latest code (or equivalent) used at contract award. Governed by suitability of the handling and recovery system, and by the ability to deploy divers. Design is based on Sea State 5-6 Significant Wave Height 3.9m as per Lloyd’s Rules Lifting Appliance Marine Environment 2017 (Table 4.4.1)
Design Guides & Classification*
Classification of Submersible and Underwater Systems
Lloyd’s Register: Code for Lifting Appliances In A Marine Environment
PD5500 Specification for Unfired Fusion Welded Pressure Vessels
The ASME Code for Pressure Vessels for Human Occupancy (used for design of acrylic view ports) *Latest code used at time of contract award
9.7m +/- 0.5m
3.2m +/- 0.25m
3.4m +/- 0.25m – including mating skirt
Total maximum weight in air
28,000kg +/- 5% (S.G. 1.000 - 1.03)
Rescue chamber capacity
18 total (17 rescues plus 1 attendant), dependant on life support requirements
Command module capacity
2 total (pilot and co-pilot)
Max operating depth
The submersible will be designed, tested and certified by Lloyds to a maximum dive depth of 500m. All functions and systems will operate as per specification
600m (60 bar)
Pressure hull test depth
840m (84 bar) – Witnessed by Lloyds Register
1000m (100 bar)
Sea water ballast tank
Internal (RC and CM)
Air buoyancy tanks
External tanks (forward, mid & aft)
Air storage tanks
2 external bottles (port & starboard)
Oxygen storage tanks
4 external bottles (port & starboard)
Trim weight (Pitch)
Adjustable pitch control via internal water tanks
Trim weight (Roll)
Adjustable roll via hydraulic port/starboard movement
Can be jettisoned in an emergency
Pitch trim capacity
Roll trim capacity
Note: To achieve greater angles, please consult
Speed (with mating skirt fitted)
Forward 3.0 +/- 0.2 knots
Reverse 2.0 +/- 0.2 knots
**Cruise 1.5 +/- 0.2 knots @ 8 hours duration **Depending upon sea conditions
2 off electric powered propulsors inc. vertical swivel axis (forward/reverse thrust)
Propulsors can be swivelled by +/- 20 degrees
2 off hydraulically powered side thrusters inc. swivel from 0° to 90° (vertical & horizontal direction thrust) 2 hydraulically powered thrusters, fixed, mounted forward and aft (lateral direction thrust)
Manual and autopilot
Navigation and communication
North seeking gyro compass, flasher/strobe, Pinger locator. DVL, altimeter, obstacle avoidance sonar CM and RC intercom system
Deck Comms, VHF radio
Under water telephone consisting of SRV transducer(s) and top side unit. Note – ship transducer supplied by shipyard (TBC)
instrumentation and control
Battery modules housed in port & starboard battery pods. Includes traction modules and instrumentation module.
Can be jettisoned in an emergency
Battery - Emergency
Lead acid batteries
Life Support consisting of:
Life support - oxygen normal
*Approx. 12 hours for 20 persons
Life support - oxygen emergency
*Approx. 96 hours for 20 persons
CO2 absorbent - Normal
*Approx. 12 hours for 20 persons*
Life Support Kits
Individual kits, containing CO2 absorbent, rations, life Jacket, space blanket, light stick and goggles
Lift point (normal)
Main single point lift (for LARS) Double lift point (crane lift)
Main lift – manual or hydraulic detachment during deployment. Manual assisted during recovery to interface with LARS / crane
Lift Point (emergency)
Soft strops for emergency recovery from sea bed to surface only
Forward & aft tow point. Aft with hydraulic detachment during deployment. Fwd manual
360° view acrylic hemispherical window
Attached to reinforced ring in pressure hull Self-weight hinged and locking mechanism
The control functions are contained in and operated from panels sited on the port and starboard walls of the compartment.
Air and oxygen controls system are contained The control equipment includes steering, ballast controls, environmental controls, sonar, auto-pilot, gyro, underwater telephone, VHF radio, echo sounder, intercom, video system.
Pilot and Co-pilot
During transfer under pressure between the rescue chamber and the DISSUB, hatch#3 between the two chambers is closed so that the two crew in the command module are not subjected to the higher pressure.
18 persons. Quantity of accommodated people in one mission: (1 RC operator plus 17 rescues).
Quantity of rescues: 17
Transfer under pressure
Mating to TUP from rear of RC (aft hatches)
Rear Annulus (TUP interface)
To provide access for the attendant and rescues to and from the RC and to provide the interface with the deck reception chamber on the mother ship enabling the rescues access to the de-compression chamber.
Rescue Chamber Hatches
Quantity of hatches: 4
Command Module Hatches
Quantity of hatches: 2
Hatch#3 (bulkhead hatch) is shared between both chambers therefore total hatches is 5
The dry mating (DMS) skirt provides a structural link between the pressure hull of LR11 and the disabled submarine.
Fairings are fitted to provide the submersible with an external surface that is clean in order to perform the following:
To protect externally-mounted equipment against impact and sagging.
To provide a flat and level upper surface to aid diver access during launch and recovery and to aid maintenance access.
To provide an externally smooth surface to aid the vehicles hydrodynamic profile and minimise drag.
There are multiple separate buoyancy modules on the vehicle assembly
Battery Pod Assemblies
Battery pod contain the traction battery modules and instrumentation module.
Each of the battery pods can be jettisoned individually should one of them become flooded or entangled
The main propulsion consists of two aft mounted, electrically-driven thrusters and port and starboard bow planes.
The port and starboard bow planes are actuated together using the main hydraulic circuit. Speed control of the two electric thruster motors is provided by variable speed drives.
The propulsors are mounted on vertical pivots allowing them to be swivelled approximately 20° port and starboard.
The auxiliary propulsion system consists of four hydraulic thruster units
Each midships thruster is mounted onto a shaft which pivots on bearings.
The transverse thrusters are fixed to the vehicle frames and do not tilt.
The two hydraulic power packs (port & starboard) are mounted externally to the main pressure hull.
Trim Weight System (Pitch)
The pitch trim weight system consists of internal ballast tanks located inside the RC and CM. Water ballast is used to adjust trim.
Trim Buoyancy System (Roll)
The roll trim weight system consists of a fixed mass which can be moved laterally. This is achieved by moving the mass port/starboard using a hydraulic actuator.
The air system is divided into two - the main and reserve systems.
Main Hydraulic System
The functions driven from the main hydraulic system are as follows:
Main propulsion swivel controls
Bow planes control
Side auxiliary thruster tilt
Skirt water ejector motive pump
Skirt flood valve
Lift line release
Tow line release
Camera pan and tilt
Main Hydraulic System Power Packs The power packs convert electrical energy from the batteries into hydraulic power for the main hydraulic system.
Two identical power packs are provided. Each power pack is divided into two parts, the electric motor and the hydraulic pump and reservoir enclosure.
General Function Valve Packs
The general functions valve packs provide control of all functions except the thrusters, which are controlled
from the thruster valve pack, and the manipulators which has its own separate valve pack.
Thruster Valve Pack
The thruster valve pack provides control for the auxiliary thrusters and isolation of the manipulator valve pack.
Emergency Hydraulic System
The system consists of a hand pump, fitted with an inbuilt pressure relief valve, this is used to pressurise a simple control system. Control is by operation of ball valves to select function.
The system controls:
Ejection of the battery pods
Release of the emergency buoy
Ejection of the drop weight
Emergency control of the main propulsion swivels Emergency control of dive planes
Emergency control of dry transfer flood valve
Electrical energy is provided by two sets of batteries, one set in each of the port and starboard battery pods. Each pod set comprising a set of batteries for traction power and one for control, instrumentation and life support power.
The battery system provides electrical power for all on board systems.
The battery system is provided with a battery management interface to monitor status (current, voltage, capacity etc.) and performance at all times. A full graphical display of battery condition is provided inside the command module.
In addition to the primary batteries, an additional pair of sealed lead acid batteries is connected in series to provide a 24V emergency supply. This is incorporated into the 24V distribution system.
Additional power can be provided as an option. Please contact us for details.
Insulation Resistance Monitoring
This monitors the integrity of the main and emergency systems and displays values of insulation resistance between these supplies and earth.
Electrical Penetration System
An extensive series of penetrators and cables is provided to interconnect the internal control and power distribution system with the external equipment sensors etc. Penetrators are also provided to transfer power and signals across the command module/rescue chamber bulkhead.
The alarms system detects alarm conditions from a number of sensors
The following alarms are provided:
a) Water Detectors
• Command Module
• Rescue Chamber
• Port and Starboard Battery Pods
• Propulsion Control Pods
b) Temperature Switches
• Propulsion Motors & Pods
c) Pressure Switches
• Maximum Depth
• Hydraulic Reservoir
The following temperatures are monitored and displayed
a) HPU’s oil temperature
b) Seawater temperature
A Sonar System will be provided comprising of a sonar processor in the command module and a Sonar Head externally mounted above the bow thruster at the forward end of the submersible.
Autopilot and Steering Control
Steering of the submersible may be performed in either manual, or automatic (autopilot) modes.
The Gyro System consists of a North Seeking fibre optic gyro unit with integral pitch and roll measurement. The output from this gyro is used to provide the autopilot heading reference.
Typical Video Cameras and Monitors
Low light cameras
Colour zoom cameras
Colour video monitors
Digital Video Recorder
A series of external lights are provided, arranged to provide good all round illumination. Each are strategically sized and positioned to assist in docking manoeuvres and personnel transfer.
An underwater telephone system will be provided complete with frequency transducers, one for upward communications the second for communications below the submersible. The up
transducer is mounted near the conning tower of the submersible the down-transducer on the underside of the pressure hull between the battery pods.
The VHF radio provides communications between the submersible and the support vessel (on deck) during launch and recovery operations
The oxygen system provides breathing oxygen for the vehicle occupants. The system is divided into the main and reserve sections. Each has its own storage cylinders, charge point and entry into the hull.
Carbon Dioxide Removal
The vehicle’s CM and RC are provided with electrically driven scrubbers to remove the carbon dioxide via an absorbent.
Each rescue is also equipped with a kit in the event of failure of the powered scrubber units or in an emergency.
Air Built In Breathing System (BIBS)
The BIBS system allows for three users in the command module and eighteen users in the rescue chamber. Thus providing for one man in addition in the command module
Each station is provided with a shut-off ball-valve in case of failure of the regulator. Each BIBS unit consists of a regulator feeding a face mask via a flexible hose.
7 function rate-controlled manipulator provides a dextrous arm capable of performing external manipulative tasks. The Manipulator system comprises a hand controller, a valve pack and a robot arm.
Low Pressure Water Jet Pump
Cutter and Pressure Intensifier
Cut wire rope up to 38mm diameter.
Provision is made for lifting LR11 off the seabed and near to the surface of the sea in the event of major submersible malfunctions. The emergency lifting capability is provided by two soft lift strops.
Fire Detection and Extinguishers
Fire extinguishers are provided both in the rescue chamber and the command module