Submarine Manufacturing and Products Ltd (SMP), a leading UK based manufacturer and…
Houlder’s Innovative Naval Architecture: Designing Mothership for SMP’s Submarine Rescue System for Indonesian Navy

Submarine Manufacturing and Products Ltd (SMP), a leading UK based manufacturer and supplier of diving and subsea rescue equipment, will provide its new Submarine Rescue System (SRS) to the Indonesian Navy. The SRS will be hosted on a mothership designed by naval architecture and ship design firm Houlder and delivered by our Indonesian strategic partner, BTI Defence.
Over the last year, we have developed the technical requirement outlining the vessel role, performance and endurance, as well as specify the main equipment required. We have extensively investigated different options across the whole design and produced a concept design package including specification, general arrangement drawing, main structure, CFD powering analysis and full intact and damage stability assessment.
The vessel’s operational requirements are different from many current rescue vessels. To fully understand its systems and their use we held in-depth discussions with the SMP team which is vastly experienced in submarine rescue. As a result, we were able to clearly identify the key drivers for the ship design.
We have developed an inventive concept that meets the needs of the SRS and Indonesian Navy, including maximising safety and efficient deployment. With the SRS requiring a bespoke dedicated rescue vessel, it allowed us to design and incorporate specific features that enhance the ship’s rescue capabilities, operability and safety.
The vessel includes an optimised aft working deck arrangement and a large, dedicated operations room with an attached communications suite, which has a clear view over the working deck to support rescue operations. The design also incorporates multiple small boats for rescue duties and a helipad that takes the appropriate medium-to-large sized rescue helicopters.
The ship will have a large permanent hyperbaric chamber and a dedicated 10 berth hospital. Permanent onboard accommodation for up to 90 people is also incorporated. This allows for total numbers to swell beyond the normal crew as required during a rescue operation. There are over 30 spare berths available and separate accommodation for rescued personnel, with up to 50 berths.
The vessel arrangement is heavily focused on function and the flow of personnel. For example, we are able to minimise the time that rescued personnel are transferred to the appropriate medical facilities on the vessel from their point of entry onto the ship. The hyperbaric chamber is located next to the hospital, and this in turn is just a single compartment away from the accommodation for medical staff, all of which are on the same deck. There is direct access from the small boat rescue zone to the medical facilities.
The vessel will feature a dedicated closed hangar with climate control for rescue equipment. This ensures the equipment is protected from the environment and remains in optimal condition. It can also be maintained more easily and ensures crew comfort is maximised whilst conducting rescue tasks – an important consideration for equatorial operations.
It is imperative that the vessel is highly reliable. The ship provides for heightened redundancy – providing for multiple rescue systems, multiple launch and recovery methods, and multiple options for emergency power. Maximising the ship’s capabilities has been paramount for our team – especially having been inspired by passionate accounts from those involved in rescue attempts. The space demands that this generates were a key challenge to overcome within in a smaller platform package, all at the right cost.
We have drawn on our hydrodynamics expertise to design a vessel that maximises speed whilst without compromising seakeeping performance to increase the operational envelope – both key capabilities for successful rescue missions. The iterative hull form optimisation process, for example, will continue to find every percentage gain, as for this ship time will be of the essence. In tandem with the hull design, we investigated many different power and propulsion options to achieve maximum speed while maintaining reliability.
The next phase will be to develop the concept into a basic design pack to a level where the shipyard will develop this into a fabrication ready design. During this detailed design phase, we will provide technical support and plan approval to BTI Defence leading up to the vessel construction.
At Houlder, we take pride in operating in truly global markets and tackling specialist naval architecture challenges like this. Read about an interesting research vessel design here.