The 35ft 6in Self-righting motor-class was a 35feet displacement hull lifeboat built in single engine form between 1929 and 1940 and in twin-engined form between 1947 and 1950. The boats were operated by the Royal National Lifeboat Institution between 1929 and 1965.
The need to provide motor lifeboats at stations using carriage launching had first been addressed with the 35abbr=onNaNabbr=on Self-righting motor type of 1921. Three of these boats were built and were to all intents and purposes pulling and sailing boats with an auxiliary engine. The definitive boat for production appeared in 1929, 6inches longer and with the same 8feet beam as the second and third 35ft types. After the first two boats had been put on station, a crash programme of production was instituted in 1931 and twelve boats were produced that year. These gave many stations their first motor lifeboats, but experience proved that stability was lacking and from ON 763 beam was increased by 5inches. The final two single engine boats saw further beam increases, to 9feet and 9feet respectively. In common with the similar but non self-righting Liverpool-class, post war production switched to twin-engined versions, but only five were built. The RNLI was increasingly switching to more stable non self-righting lifeboats and the single engine 35ft 6in Self-righting motors were replaced at most stations by Liverpool-class boats in the early 1950s after only around twenty years service. The twin-engined boats had even shorter lives, being replaced at three stations by Liverpools and at the other two by 37abbr=onNaNabbr=on s after less than fifteen years service.
The challenge of producing a motor lifeboat light enough to be manhandled for carriage launching resulted in a boat weighing around NaNLT. The single RNLI-designed, Weyburn Engineering built AE6 6-cylinder petrol engine produced 35 bhp and sat in a watertight engine room beneath pent roof access hatches ahead of an aft cockpit shelter from which the mechanic operated the engine controls. Apart from a small shelter forward the boats were open. As described above, beam was increased during production in an attempt to improve stability. After World War II, five twin engined boats were built which had a beam of 10abbr=onNaNabbr=on and a larger shelter covering the engine room and very similar to the contemporary twin engined Liverpools. The first two of these boats were powered by two 18bhp Weyburn AE4 4-cylinder petrol engines, but the final three had 20bhp Ferry FKR3 3 cylinder diesels.
| ON | Name | Built | In service | Stations | Comments[1] | |
|---|---|---|---|---|---|---|
| 726 | City of Nottingham | 1929 Saunders-Roe, Cowes | 1936–1949 | Sold in 1950. August 2021, Restored to original at Lawrenny Quay, Daugleddau estuary. | ||
| 727 | Westmorland | 1930 Saunders-Roe, Cowes | 1930–1940 1940–1951 | Sold June 1951. Renamed Swallow. Owned by Northern Shipbreakers, Peterhead in 1961 | ||
| 737 | Louisa Polden | 1931 Saunders-Roe, Cowes | 1931–1951 | Sold in 1951. Broken up at Stockton-on-Tees in the 1980's | ||
| 738 | J.H.W. | 1931 J. Samuel White, Cowes | 1931–1939 1939–1947 | Padstow No.2 | Sold April 1948. Renamed Navette. Last seen, Thames area, 1990's | |
| 739 | Lily Glen - Glasgow | 1931 Saunders-Roe, Cowes | 1931–1952 | Sold May 1952. Renamed Seeker II. June 2014, derelict in a field off Harbour Road, Rye | ||
| 740 | Cyril and Lilian Bishop | 1931 J. Samuel White, Cowes | 1931–1950 | December 2022, on permanent display, Old London Road, Hastings. | ||
| 741 | Morison Watson | 1931 Saunders-Roe, Cowes | 1931–1953 | Sold in 1953. Renamed Scauronian. Broken up at Terregles, Dumfries, August 1998. | ||
| 742 | Herbert Joy II | 1931 J. Samuel White, Cowes | 1931–1951 | Sold in 1951. Renamed Viking Raumur. Broken up at Acaster Boatyard, York in the 1980's. | ||
| 743 | John and Sarah Eliza Stych | 1931 Saunders-Roe, Cowes | 1931–1938 1938–1939 | Padstow No.1 | Wrecked on service 23 Jan 1939, seven crew lost. | |
| 744 | Laurana Sarah Blunt | 1931 J. Samuel White, Cowes | 1931–1952 | Sold in 1952. Renamed Laurana (UL3), broken up west of Ullapool, 2005 | ||
| 745 | Lady Harrison | 1931 Saunders-Roe, Cowes | 1931–1948 1949–1951 | Sold in 1952. Burnt at site of Husbands Shipyard, Marchwood, Southampton, April 2005. | ||
| 746 | William Maynard | 1931 J. Samuel White, Cowes | 1931–1939 1939–1941 1941–1948 1948–1949 1949–1953 | Relief fleet Whitehills Relief fleet | Sold February 1953. Renamed Endura. Lost in Channel off Dungeness, December 1970. | |
| 747 | Stanhope Smart | 1931 Saunders-Roe, Cowes | 1931–1947 1947–1951 | Padstow No.2 | Sold in 1951 to Liberia. | |
| 748 | Mary Ann Blunt | 1931 J. Samuel White, Cowes | 1931–1950 | Sold in 1951. With Balbriggan Sea Scouts, 1951 | ||
| 752 | John and William Mudie | 1932 Thorneycroft, Chiswick | 1932–1950 | Sold June 1951. Renamed Sharon. July 2022, ashore at Kingholm Quay, Dumfries. | ||
| 756 | Civil Service No.4 | 1932 J. Samuel White, Cowes | 1932–1948 | Damaged beyond repair on service 16 June 1948, although last reported as a yacht in Newfoundland in the 1970's | ||
| 757 | Frederick Angus | 1932 J. Samuel White, Cowes | 1932–1949 | Sold August 1949. Renamed Yr Ystwyth. August 2015, Last reported damaged, at Oakford, Nr Aberaeron. | ||
| 763 | Caroline Parsons | 1933 J. Samuel White, Cowes | 1933–1938 | Wrecked on service 31 January 1938 | ||
| 767 | Catherine Harriet Eaton | 1933 J. Samuel White, Cowes | 1933–1953 | Sold in 1953. Renamed Sharan, wrecked in Martins Haven Bay, Pembrokeshire, 1976. | ||
| 768 | Thomas and Annie Wade Richards | 1933 J. Samuel White, Cowes | 1933–1953 | Sold in 1953. Renamed Dolphin (AB6), believe broken up at Tranmere 2003/04 | ||
| 785 | Sir Heath Harrison | 1936 J. Samuel White, Cowes | 1936–1949 1949–1955 | Relief fleet | Sold January 1956. Renamed King John III. December 1979, last reported as Pilot Boat, Western Dock, Dover in the 1970's | |
| 826 | Guide of Dunkirk | 1940 Rowhedge Ironworks, Rowhedge | 1941–1963 | Lizard-Cadgwith | Sold in 1963. December 2022, privately owned at Mevagissey Harbour. |
| ON | Name | Built | In service | Stations | Comments | |
|---|---|---|---|---|---|---|
| 851 | Tillie Morrison, Sheffield | 1947 J. Samuel White, Cowes | 1953–1959 | Capsized on service at Bridlington 19/8/1952, one crew lost. Sold November 1959 | ||
| 878 | M.T.C. | 1950 Groves & Guttridge, Cowes | 1950–1963 | Sold in 1964 | ||
| 879 | E.C.J.R. | 1950 Groves & Guttridge, Cowes | 1951–1956 1956–1963 | Relief fleet | Capsized on service 8/12/1954, three crew lost. Sold March 1963 | |
| 880 | Isaac and Mary Bolton | 1950 Groves & Guttridge, Cowes | 1951–1963 | Sold in 1964 | ||
| 881 | City of Leeds | 1950 Groves & Guttridge, Cowes | 1951–1965 | Sold March 1965 |