She initially served in St Peter Port on evaluation trials, and from 1974 was based at Barry Dock Lifeboat Station.

[1] The second Arun lifeboat was the Sir William Arnold, which had a lower freeboard aft and had a redesigned wheelhouse.

[2][3] During her time in service, the Sir William Arnold embarked on more than 500 rescue missions and saved 224 lives.

[3] Her most famous rescue was of 29 crew and members of their families from the MV Bonita on 19 December 1981 in hurricane conditions.

[4] After being sold in 1997, the Sir William Arnold was fitted out as a leisure craft and renamed Our Lady and then Theocrat.