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Shannon Sea Trials – Part 3

Shannon Sea Trials case study this covers the rigorous testing and Sea trials carried out by Berthon and the RNLI before the boat can be presented for acceptance.

The sea trials are split into several different areas to maintain focus for each individual trial:

Initial sea trial

  • Representatives from both Scania and Hamilton Jet are onboard to ensure correct operation of engines and jets.
  • A slow and controlled ramp up of engine RPMs is carried out over the course of an hour with regular visual inspections in the machinery spaces.
  • Once the trials team is happy with the machinery some full speed runs are carried out so that Scania can obtain engine data for their records.
  • After a few hours running the jets are tested at various engine revs and loads to ensure correct operation occurs with no alarms.



RNLI Shannon 13-13 Sea Trials

With the boat back alongside our work berth at the yard, the trials engineer and Coxswain carry out a full inspection of the boat to ensure that all the boat is ready for its next trial.

Machinery and Vibration trial

  • A series of vibration readings are taken from engine and gearbox mounts to ensure that the engines and drivetrain are within the vibration tolerances.
  • A number of noise readings are also taken throughout the boat and compared to previous craft to ensure build consistency and that the operators are not exposed to too much noise.

Electronics and SIMs trial; the Shannon class lifeboat has an enormous amount of technology packed into a relatively small space. This trial tests each individual piece of electronics equipment and ensures that there is no interference between them. The following equipment is tested with set procedures during the trail:

  • Radar.
  • 2 fixed VHF radios.
  • 1 portable VHF radio.
  • Direction finding equipment (VHF and EPIRB).
  • MF radio set.
  • AIS – Automatic Identification System.
  • SIMs – System and information management system.
  • Intercom and talkback system.

RNLI Shannon 13-13 Sea Trials

Speed and Endurance Trial;
This is to ensure consistency across the Shannon build, speed trials are carried out at full speed and various other intermediary engine speeds. After the speed trials are completed, the Endurance trial begins. The boat is run at full speed for at least 4 hours to ensure that all the machinery operates with no faults at full load.

With the ‘Yard’ trials completed, the RNLI then send in a team from the operations staff for the ‘Proving trial’. The proving trial is 5 days long and is primarily looking for any build defects and mechanical failures. The Berthons trials Coxswain is also onboard for the proving trial as a yard representative and to facilitate any repairs if any mechanical failures should occur.

The last trials in the Shannon program take place on the acceptance week. This is split into 2 different trials the first of which is called a Hull and Equipment trial. This is carried out by RNLI operations and engineering staff and is a very thorough examination of both the build records and the boat itself, with a sea trial taking place to carry out some spot checks on different pieces of equipment.

The proving trials crew –

  • Oliver Phillips – Berthon Trial Coxswain
  • Martin Phillips – Fleet Staff Coxswain
  • Nicholas Rigler – Technician Mechanic – ALC RNLI HQ
  • Andy Williams – Mechanic Exmouth Lifeboat (RNLI Shannon 13-03)
  • Stephen Lowe (Aka Teeny) – Mechanic Tenby Lifeboat

RNLI Shannon 13-13 Sea Trials

The second trial is called the Acceptance trial; this is the final sign off on the boat with senior RNLI personnel attending to carry out an inspection followed by a sea trial. If this all goes well, they officially accept the boat into the RNLI fleet.

Dominic May, Berthon, Charles Hunter-Pease RNLI Chairman - 13-13 Acceptance DayCharles Hunter-Pease RNLI Chairman accepts an aneroid barometer from Berthon Director, Dominic May. The barometer was given by the RNLI to the Kingsdown Lifeboat station in the 1840s and we hope it’s found a good home, now that it has found it’s way home!

This entire process is designed by the RNLI and facilitated by Berthon to allow the best boat possible to enter the RNLI fleet so that the volunteers around the UK and Irish coasts can continue to carry out lifesaving rescues at a moment’s notice and have complete trust in their lifeboats.


Berthon will be pleased to answer any questions or request for information on this case study.

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View the rest of this series of case studies.

Part 1 – The commissioning, trials and acceptance of Shannon class lifeboat

Part 2 – Shannon Launch and Commissioning