The Sea Class 15 officer training boat (OTB) is used by the Royal Navy for cadet training. Credit: Royal Navy.
The Sea Class 15 boat is highly modular and can be reconfigured for different roles according to requirements. Credit: Royal Navy.
The OTB features on-board training and accommodation facilities. Credit: Royal Navy.

The Sea Class 15 Officer Training Boat has been designed and developed by Atlas Elektronik UK for naval cadet officer training purposes. It features in-house training facilities and accommodation units.

The UK Royal Navy’s Britannia Royal Naval College (BRNC), Dartmouth, inducted eight new Sea Class 15 OTBs in January 2022, replacing the ageing fleet of P1000 class picket training boats.

The old training boats were retired at the end of 2021. The new Sea Class 15 boats were procured as a part of Project Vahana, which aims to replace a range of craft and workboats across the fleet with a small flotilla that will provide modern and reliable training.

The boats under the project will have a modular design, as well as standard maintenance and spare parts. The missions of the project’s new boats range from diving and survey operations to training, passenger transfer for aircraft carriers, and general duties.

Orders and deliveries

Atlas Elektronik UK received a six-year contract worth £48m ($62.5m) for the supply and support of up to 38 workboats for the UK Ministry of Defence (MoD) in August 2017.

It delivered the first Sea Class 15 OTB under the contract to BRNC in November 2020.

Sea Class 15 boat design and features

The Sea Class boat, which is a Category 2 vessel, can be easily reconfigured based on the mission role, enabling it to be used for a range of tasks.

The twin-hull design of the OTB provides more stability and allows it to carry heavy payloads at high speed. The hulls are made of glass-reinforced plastic.

The high commonality of components enables simplified maintenance and minimal training requirement.

The boats can be used for training activities, including traditional basic seamanship and advanced navigation skills.

Equipped with classrooms and accommodation facilities, such as bunks, shower, and galley with boiler and microwave, the boat can be used to train up to 16 cadets. It also features networked workstations and shock mitigation seating.

The network capability allows cadets to develop basic planning and command of a task group. A briefing area on board the boat is installed with a large screen that displays charts and real-time navigational data.

The Sea Class 15 boat has a length of 15m, beam of 4.4m and maximum draft of 0.85m. The overall height with its mast lowered is 3.44m, while height with the mast raised is 5.74m.

The OTB has a nominal lightship displacement of 20,400kg and full load displacement of 23,150kg. It can carry a payload of up to 7,000kg.

Navigation and control

The boats are fitted with a navigation suite that complies with International Maritime Organization (IMO) standards and is compatible with the Royal Navy’s surface fleet.

The engines are operated electronically for ultimate control and manoeuvrability.

Propulsion and performance

The cadet training boat is equipped with a twin-engine propulsion system integrating HamiltonJet waterjets. It is equipped with a HamiltonJet waterjet control system called Blue Arrow.

The Blue Arrow electronic control package features single or twin waterjet units along with interfaces for control of the throttle and gearbox. It also includes ahead/astern and steering controls, which enable the operator to have complete control over vessel manoeuvring.

The boat can operate at a speed of more than 25kt. It is transportable by road or by sea.