Update: 01-03-2025
David Alan was born on 7 February 1891 as 1st child of Charles Alexander Stevenson and his wife, Jessie Maclellan. He was named after his uncle, David Alan Stevenson but was generally called Alan. The family lived at 9 Manor Place in Edinburgh's West End.
David Alan was educated at Edinburgh Academy (1899 - 1903) and then studied Civil Engineering at Edinburgh University where he graduated as Bachelor of Science in 1914.
David Alan joined in 1912 the family business designing lighthouses. After the First World War, he was taken into partner in 1919 of the business. In the First World War he served in the Royal Marines as an Engineer.
In 1919 he was elected a Fellow of the Royal Society of Edinburgh. His proposers were Charles Alexander Stevenson (his father), David Alan Stevenson (his uncle), William A. P. Tait, James Simpson Pirie, Sir Thomas Hudson Beare and Harry Rainy.
By the 1920’s the great days of lighthouse building in Scotland had ended and the firm was increasingly involved in the maintenance of lighthouse stations and the modernization of the equipment in these lighthouses.
In 1925–26 he surveyed over 100 lighthouses from Siam to Aden for a report to Government of India, while in the 1930s, he superintended the deepening of the Clyde from Port Glasgow westwards, to allow the passage of the Queen Mary after her launch.
By 1936 David Alan Stevenson had grown impatient with the uncertainty of obtaining the post of engineer to the Northern Lighthouse Board which David Stevenson, then aged eighty-one still held. The resulting disagreement resulted in David Stevenson's withdrawal from D. and C. Stevenson, thereby ending the firm's long-standing association with the NLB. The firm D. and C. Stevenson was reformed in 1936, as A. and C. Stevenson, at 90A George Street, Edinburgh.
The new firm's workload was much reduced, relying principally on commissions as joint engineers to the Clyde Lighthouses Trust. In 1940 Charles Stevenson retired, after which Alan Stevenson continued to act solely as the trust's engineer until his own retirement in 1952.
By the time of his retirement Alan Stevenson had become increasingly involved in researching his various historical interests. In 1949 he published an account of Robert Stevenson's English Lighthouse Tours, 1801, 1813, 1818. This was followed in 1950 by The Triangular Stamps of Cape of Good Hope, for which he was awarded the Crawford medal of the Royal Philatelic Society and, in 1959, by his authoritative The World's Lighthouses before 1820.David Alan was great grand-son of Robert Stevenson FRSE 1797-1842, grand-son of David Stevenson FRSE 1853-85 and nephew of David Alan Stevenson FRSE 1885-1938. He married Jessie Laura Margaret MacLellan (1897–1975) on 5 June 1923. They had one son and two daughters.
In 1951, Stevenson was awarded the Crawford Medal by the Royal Philatelic Society London for his work The Triangular Stamps of Cape of Good Hope.
He died on 22 December 1971 and was buried in the first northern extension to Dean Cemetery in western Edinburgh. The grave lies immediately alongside his parents.