J.I. Thornycroft Ltd

Please note that the history of Vosper Thornycroft can be found elsewhere on this website.

JI Thornycroft
JI Thornycroft
Often simply known as Thornycroft, the company was founded on a strip of riverside land in Chiswick, London in 1866.
John Isaac Thornycroft had displayed his early talent by building a steam-powered vessel called ‘Nautilus’, when aged just 16 years.  It proved robust enough to allow his family to follow the University Boat Race along the Thames and so impressed was his sculptor father, Thomas Thornycroft, that he purchased a riverside workshop for John to create his company.
This was followed in 1877, by an order for HMS Lightning for the Royal Navy. HMS Lightning was the first sea-going steam vessel to carry torpedoes and it was later re-designated as Torpedo Boat No1.  Torpedo boats soon became the ‘weapon of the future’ and through this design, John Thornycroft developed into a major supplier to the navies all around the world.
Whilst Thornycroft himself concentrated on the design work, it was his brother-in-law John Donaldson who managed the business side and generated the cash flow needed to undertake the growing number of contracts.
Upon Donaldson’s death in 1899, a group of wealthy businessmen invested into the company and through their various concerns Thornycroft forged links with other ship yards and boat-builders such as John Brown at Govan, WG Armstrong on Tyneside and Vickers in Barrow.
One notable new Board Member (and later Chairman) was William Beardmore, who provided the necessary capital to create the public company known as John I Thornycroft & Company Limited. Beardmore also sat on the board of many companies throughout the UK involved in numerous branches of engineering from munitions and armaments to aeroplane engines and motor cars.
Chiswick in late 19th Century
Thornycroft Shipyard in Chiswick in late 19th Century
The growth of the order book and the overall size of the vessels being created on the Thames continued to cause difficulties and it soon proved to be a difficulty for Thornycroft as many could only just scrape under Chiswick and Hammersmith Bridges. 
A solution emerged in 1904, when the Oscar Mordaunt Yard at Woolston (Southampton) became available. The site was quickly acquired by Thornycroft who steadily migrated the majority of the business to the south coast. At its peak Chiswick had employed over 1,700 men and gradually, those that could, transferred to the new yard.
William Beardmore resigned as Chairman in 1907, making way for a new board led by Thornycroft’s son John Edward Thornycroft. He managed the company working alongside his cousin, the confusingly named Thornycroft Donaldson.
The first ship built by the new company was HMS Tartar, a ‘Tribal Class’ Destroyer which led to the yard creating a further 37 Destroyers for the Royal Navy (and several more for export) before the outbreak of World War 1. 
During the conflict, the company built another 26 Destroyers and 3 Submarines for the Royal Navy. In addition, they designed and built a multitude of smaller vessels including the Coastal and Motor Torpedo Boats designed by Thornycroft Senior. John Thornycroft had bu now retired from the company and lived on the Isle of Wight, where sadly he passed away on 28th June 1928.
Throughout the war, J.I. Thornycroft Limited continued with the production of small yachts and vessels from Platt’s Eyot, an small island on the Thames, near Hampton Court. The company had been resident on the island since 1904 and from where it continued small bespoke vessels until the 1966 merger with Vosper. Even today, Platt's Eyot has a healthy boating community where the Thornycroft traditions are still upheld. 
HMS Mohawk
HMS Mohawk, one of 27 Tribal-class destroyers (16 were built for the Royal Navy) during the 1930s
After World War 1, the company continued to build destroyer-sized warships both for the Admiralty and for export customers, and it profited greatly from the subsidised shipbuilding programmes of the late 1930’s. The inter-war years also saw a concentration on a range of civilian ships such as SS Robert Coryndon, a passenger and cargo ship for service on Lake Albert, Uganda from 1930.
With the coming of World War 2, the Woolston Shipyard was bombed several times during the Blitz, predominantly because the Supermarine Spitfire Works was the next industrial facility upriver. Spitfire historians often tell the reverse story although both seem to ignore that nearby Southampton was a major cargo port for the movement of vital supplies.
J.I. Thornycroft built a vast number of ships during the war years, ranging from Minelayers, Destroyers and Corvettes to Landing Craft and RAF Rescue Launches.
Additionally, they also managed to produce the Fast Mine-layer HMS Latona (M76) which, at 2,600 tonnes, was the largest Royal Naval ship of the time. Sadly, HMS Latona met her fate just a year after her launch when she sunk off Libya in 1941.
One of the greatest achievements by J.I. Thornycroft Ltd during the war years was the production of the first successful Landing Assault Craft (LAC) for the Royal Navy. There had been a few previously unsuccessful designs by smaller shipbuilders but it was the Thornycroft design which was the closest to the  Navy specification, which called for a low silhouette, silenced engines and shallow draught. The Thornycroft design became the benchmark of all future designs and their name is now forever linked with this category of vessel.
With the run-down of the Royal Navy after 1945, J.I.Thornycroft Ltd reverted to what can only be called ‘lean production’, with work being confined to the building tugs, ferries, launches and barges, alongside the occasional naval order.
Soon after however, things started to look up and the company built and had launched the Weapons Class Destroyers HMS Crossbow (G96/D96) and HMS Culverin (D28) by 1946.  
In 1951, these were then joined by the Daring Class Destroyer HMS Duchess (D154) although, of the 16 planned Daring Class Destroyers, only 1 of the 8 finally completed vessels was built at Woolston. 
Commandant Quere.
Commandant Quere (1948) for the Marseille-Corsica service, the first postwar delivery to the Mediterranean fleet.
The Korean War provided a welcome respite in the famine of orders on the south coast with the construction of 10 x Ton Class Wooden Minesweepers and 3 x Frigates at Woolston.
At the very start of the 1960s, a third in the line of those named John Thornycroft took charge of the company. The founders grandson, John Ward Thornycroft, led the company into the opening a new yard for the building of yachts, utility craft and motor launches in Singapore. This business was known as Vosper Thornycroft Uniteers is covered elsewhere on the website.
Also during 1960, the Type 12 Frigate HMNZS Otago (F111) was delivered to the Royal New Zealand Navy although by this time new naval orders were once again very, very scarce.
One of the biggest problems that J.I. Thornycroft Ltd experienced was a real lack of weapons expertise and they found that all new orders (which also included weapons provision) were going to Vickers Shipbuilding at Newcastle or Barrow, both of whom were competing in the same market for a falling numbers of orders.
The Tribal Class General Purpose Frigate HMS Gurkha (F122) was delivered and commissioned to the Royal Navy by Thornycroft in 1963 although again, only one order in the class was awarded to the Woolston Yard, the others being constructed just a few miles away at the HM Dockyard, Portsmouth.
The Leander Class Frigate HMS Juno (F52) was finally laid down in 1964, as part of a major program for 26 vessels. Yet again, the orders for these were spread throughout the UK Dockyards, in order to maintain a failing industrial reliance on business from the MoD.
The Minelayer HMS Abdiel (N21) was laid down in the final days of J.I. Thornycroft Ltd in 1965, along with two 78ft patrol boats for Kuwait.  All 3 were finally completed under the new name of Vosper Thornycroft.
Soon after the merger in 1966, both the Thornycroft Woolston Yard and the Vosper Portchester Yard received an enormous amount of investment and underwent massive improvements whist sadly, the Thames Yard at Platt’s Eyot finally closed its doors.


1866         John I Thornycroft & Company                                                    
1966 Vosper Thornycroft
1977 British Shipbuilders
1985 Vosper Thornycroft
2002 VT Group
2008 BVT Surface Fleet
2009 BVT Surface Ships Limited
2011 BAE Systems Maritime


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