John I. Thornycroft & Company

John I. Thornycroft & Company Limited, usually known simply as Thornycroft was a British shipbuilding firm started by John Isaac Thornycroft in the 19th century.

History
The 16-year-old Thornycroft, helped only by his younger sister, began to build his first small steam launch in 1859 in his father's back garden at Chiswick on the River Thames. He returned from an apprenticeship in Glasgow in 1864 and began to build more steam launches.

Thornycroft first began shipbuilding at Church Wharf in Chiswick in 1866, when the plot of land which became the nucleus of the shipyard was purchased. Here, the first instance was built of what would become the torpedo boat, the Rap for Norway in 1873. This was followed by HMS Lightning for the Royal Navy in 1877.

In June 1904 the company decided to relocate to Woolston, Hampshire, where it acquired the shipyard owned there by Mordey, Carney & Company, and in 1908 they also set up the Hampton Launch Works on Platts Eyot, an island on the Thames at Hampton, Middlesex. The former yard at Chiswick closed in August 1909. The first ship built by Thornycrofts for the Royal Navy at the Woolston Yard was the Tribal-class destroyer HMS Tartar.

John Isaac Thornycroft died in June 1928, but his role as chairman of the company had been taken by his son, John Edward Thornycroft in 1908.

Woolston built the ferry SS Robert Coryndon for Uganda in 1930. She also survives, but as a half-submerged wreck on the shore of Lake Albert.

Thornycroft continued to build civilian vessels. The Hampton Launch Works built yachts including Enola (1928), Estrellita (1934) (now called Rake's Retreat), Aberdonia (1935),  and Moonyeen (1937). The pre-war motor yacht Prunella may also have been built at Hampton. These four have survived and are now recorded on National Historic Ships' National Register.

The first seaworthy Assault Landing Craft (ALC), later renamed LCA, Landing Craft Assault, ordered built for the British Navy were by Thornycroft. The first prototype ALC No 1 was built by J. Samuel White of Cowes to a design by Fleming Jenkin, but it was not very successful. Thornycroft's design was much closer to what the navy wanted, with its low silhouette, silenced engines and shallow draught. Designated ALC No 2, it was 41 ft 6 in long over all and driven by two Ford V8 engines of 65 bhp each. The design was slightly modified by the Admiralty and some 1,929 were built during the World War II. In 1944 sixty were being built each month. The LCA was reasonably seaworthy, so long as waves were less than 5 ft high. In heavy seas the situation could become critical and a number of LCAs converted to support craft disappeared in the choppy seas of D-Day, 6 June 1944. In 1944 267 were lost (out of 371 losses during the whole war).

In 1955, the company built Scillonian, a passenger ferry built for the Isles of Scilly Steamship Company.

In July 1960 John Ward Thornycroft, John Edward Thornycroft's son, replaced his father as chairman of the company.

In 1962, John I. Thornycroft and Sons was building wooden yachts in Singapore.

Thornycrofts merged in 1966 with Vosper & Co., part of the David Brown Group, to form one organisation, although the formal merger to create Vosper Thornycroft took place in June 1970. The company now trades as VT Group.

Royal Navy classes built by Thornycroft

 * D class destroyer (1913)
 * Coastal Motor Boats
 * Thornycroft type leader
 * Thornycroft M class destroyer
 * Type IV Hunt class destroyer
 * Landing Craft Assault