McLachlan-class lifeboat

The McLachlan-class lifeboat was an A-class lifeboat operated by the Royal National Lifeboat Institution (RNLI) of the United Kingdom and Ireland from 1967 to 1988. It was replaced by the B-class (Atlantic 21).^[1]

A-504 is preserved at Chatham
Class overview
Name	McLachlan class
Builders	William Osborne, Littlehampton
Operators	Royal National Lifeboat Institution
Preceded by	Hatch
Succeeded by	Atlantic 21
Built	1967–1973
In service	1967–1988
Completed	10
Retired	10
General characteristics
Length	18 ft 6 in (5.64 m)
Beam	8 ft (2.4 m)
Propulsion	2 x 60 hp inboard engines with sterndrives
Speed	22 knots (25 mph; 41 km/h)
Complement	2-3

History

The McLachlan-class lifeboat was the second type of the 1960s fast Inshore lifeboat in service with the RNLI. It was designed by J. Allen McLachlan MRINA, a naval architect, former RNLI chief draughtsman and partner at longtime yacht and lifeboat designers G. L. Watson & Co. of Glasgow.^[2]

The first trial boat, numbered 18-02 by the RNLI, was built by W. A. Souter of Cowes. The boat was constructed from 3 layers of mahogany with foam-filled watertight compartments, and was noted by its use of a 'ragged chine hull', with nine chines that cushioned the hull and reduced pounding. The helm was in a standing position, in a sunken bridge deck, with a weathershield in front of the controls. A 90 hp. Evinrude engine gave a speed of 20.9 knots.^[3]

in September 1969, following successful trials, the RNLI placed an order for 4 boats with boat-builder William Osbourne of Littlehampton, to be constructed with GRP hulls, fitted with twin sterndrive Ford 60 hp marinised petrol engines, and each costing £3,400. 18-02 would later be fitted with twin 47 hp Perkins diesel engines. William Osborne built a further five McLachlan lifeboats in the 1970s. Most remained afloat, but two were kept on carriages. The one at Weston-super-Mare being launched down a long slipway and that at Peel IOM was launched with the aid of a tractor.^[3][4][5]

McLachlan lifeboat stern view

In the early 1970s, it was decided to reclassify the 17 and 18-foot boats as A-class lifeboats, and their numbers were changed according; 18-004 becoming A-504, 18-007 becoming A-507 etc.^[6]

Although not classed as lifeboats, two further McLachlan designed boats were constructed for use as Boarding boats at Humber Lifeboat Station, (BB-239) and (BB-240).^[6]

A-504 (formerly 18-004) at Weston-super-Mare, was launched at 10:30pm on the 13 September 1975 into an easterly gale, to a motor-boat stranded on the rocks. In difficult conditions, 5 people were rescued. Julian Morris was awarded the RNLI Bronze Medal, and crew members Bernard Watts and Ian Watts both received the Thanks of the Institution inscribed on Vellum. The boat is now on display in the RNLI Historic Lifeboat Collection at Chatham Historic Dockyard.^[6][7]

All the McLachlan lifeboats had been retired by the late 1980s, with the exception of the prototype boat, which went on to be a boarding boat at Humber until 1994.^[6]

Fleet

Op. No.[a]	Old Op. No.[a]	Built	In Service[6]	Station	Comments[6]
A-503	18-02	1967	1967–1970 1971 1971 1971–1972 1975–1994	Eastney Poole Weston-super-Mare Pill Humber Boarding Boat	Prototype
A-504	18-004	1970	1970–1983	Weston-super-Mare	On display at the RNLI Historic Lifeboat Collection within Chatham Historic Dockyard.
A-505	18-005	1970	1970–1971 1972–1974 1975 1975–1987	Eastney Oban Eastney Humber (Boarding boat)	2018, At RW Davies, Saul Junction Marina undergoing restoration
A-506	18-006	1972	1972 1972–1979 1979–1980	Peel Relief fleet Plymouth
A-507	18-007	1972	1973–1976 1977–1979 1979–1980 1980–1983	Peel Plymouth Relief fleet Plymouth	2024, Undergoing Restoration In Exmouth, Devon
A-508	18-008	1971	1971–1974 1976–1979 1980–1988	Eastney Invergordon Falmouth
A-509	18-009	1972	1972–1976 1978 1978–1988	Plymouth Brighton Relief fleet
A-510	18-010	1973	1973–1974 1975–1984 1984–1987	Pill Ramsgate (Boarding Boat)	August 2020, Private ownership, Bristol
A-511	18-011	1973	1973–1982 1984–1985	Oban Relief fleet	Sold. 1985. Renamed Kim O. December 2023, for sale at Stokesley, N Yorks. (Ebay)
A-512	18-012	1973	1975–1987 1988	Torbay Falmouth

1. Op. No. is the RNLI's Operational Number of the boat carried on the hull.