+49 2641 3703 – 0 +49 2641 3703 – 199 info@moench-group.com

On board HMS Mersey

At DSEI MONS visited HMS Mersey and had an introduction of the equipment key to its missions.

The Royal Navy’s HMS Mersey is one of three ‘River’ class patrol vessels tasked to carry out exclusive economic zone (EEZ) patrolling. MONS took the opportunity offered during DSEI to do a tour visit of the ship and speak to Lieutenant (Lt) Tristan Bell, ship’s Navigating Officer, and Lieutenant Commander (Lt Cdr) George Storton, Commanding Officer.

We are a crew of 48, but only ever two thirds of the crew are on the ship at one time while the rest is on leave,” says Lt Bell. The crew spends two weeks at sea, then two days back at a port for crew rotation and other logistical needs: “This allows the ship to be at sea 320 days per year, which means that with our sister ships we are constantly patrolling UK waters,” says Lt Cdr Storton.

HMS Mersey’s key capability for its EEZ missions is its new BAE Systems 24 Pacific craft, which it received in the summer of 2017. “The new ship is heavier, which means it can support higher sea states (sea state 5 for launching and sea state 4 for boarding), it is bigger, thus fitting more people on board, it is faster and it allows us to launch the boat with the crew on it, making the launching and recovery of the boat much more efficient,” continues Lt Cdr Storton. The new craft is used on a day-to-day basis for a wide variety of operations, ranging from routine inspections of fishing vessels to delivering humanitarian aid and recovering man overboard. The ability of carrying out such different missions is a result of the modular design that allows HMS Mersey’s crew to easily remove two seats at the front and either keep that space to allow a person to lie down (if in recovery mode) or carry out supplies for a humanitarian mission, or mount a General Purpose Machine Gun (GPMG) in the event of a non-compliant boarding.

Going up to the bridge, Lt Bell indicates that there are always at least two crew working there at any one time, and that when the ship is coming into a port or into much more confined areas like the Thames on the way to London, the crew increases in order to monitor all sides of the ship and make sure to avoid collision.

Preventing accidents at sea is a major priority for us and we are constantly training to make sure that we are capable of respecting International Regulations for Preventing Collisions at Sea (COLREGS),” says Lt Bell. “As such, all crew working on the bridge have to take a monthly exam on COLREGS, with a 95% pass mandatory for all officers and 100% for the Navigating Officers and the Commanding Officers.”

In addition to the regular examination on COLREGS,” Lt Bell adds, “all crew working on the bridge have to be able to use traditional means of navigation, such as a gyro and a sextant, to be able to navigate in the event that the electronic navigation system fails.” The electronic navigation system collects and analyses all the data received from the different sensors and systems on the ship, including Kelvin Hughes radar, which works on X-band (8.5-10.6 giga hertz (GHz)) and S-band (2.3-2.5 and 2.7-3.7 GHz).

Although HMS Mersey’s missions rarely require it to open fire on other ships, it is nonetheless equipped with three main weapon systems. These include a 20mm standalone anti-surface gun located at the fore and a 7.62mm GPMG located portside, which are used to fire warning shots, as well as a 5.56mm rifle, also located at portside, which is used for protecting the ship. The officer discussing the weapons, however, noted that since he has been working on HMS Mersey these weapons have not been fired. “We do nevertheless use them for training regularly, to make sure that if there is a need one day to fire warning shots or protect the ship the crew will know what to do,” indicates Lt Bell.

Back on the bridge, Lt Cdr Storton gives a brief overview of the missions of the ship: “We spend 320 days at sea per year, and are involved in a wide variety of missions that are not limited to monitoring fishing boats but also include working with European partners on migration missions and escorting foreign vessels. However, monitoring fishing vessels does constitute a significant part of our duties and is very important for us because fishermen out at sea are also our eyes and ears out there and can inform us of anything that appears abnormal. This can include sighting of suspicious vessels but also decreasing fish stocks in certain areas. Building a relationship with fishing boats is key to our ability to provide a complete picture of what goes on in UK EEZ.”

MONS also enquired, in conclusion, on the number of women that were present in the crew: “Currently there are six women in our crew, but this varies significantly every year. Last year, for instance, we had over ten women on board, and maybe next year we will have closer to twenty. Generally speaking, in any case, the Royal Navy does have a good female representation,” Lt Cdr Storton concluded.




Related Posts

Publish date


Sign up to our newsletter and stay up to date.




Components / Systems


Defence Business

Homeland Security

International Security


Latin America (Spanish)



Training & Simulation


Special Forces



Contact Us

Contact Info

Mönch Verlagsgesellschaft mbH
Christine-Demmer-Straße 7
53474 Bad Neuenahr – Ahrweiler

+49 2641 3703 – 0

+49 2641 3703 - 199

Follow On