# Ricardo PLC

Ricardo PLC is a British firm that provides engineering, environmental and strategic consultancy services. Founded by Sir Harry Ricardo, it based at Shoreham-by-Sea, West Sussex. It is listed on the London Stock Exchange.

## History
### Early history

The company was founded by Sir Harry Ricardo as Engine Patents Limited in February 1915. Later in 1915, during the First World War, the company helped develop a 600 brake horsepower (450 kW) engine for a flying boat. In spring 1916, it helped with the design of a device to manoeuvre 25 tonnes (28 tons) battle tanks into position aboard railway wagons. Later in 1916, it designed a 4-stroke crosshead-type engine for the Mark V tank which produced 150 brake horsepower (110 kW) but emitted no visible smoke detectable by the enemy.
After the war, the company developed a side-valve engine, which minimised the clearance between the piston and cylinder head thereby achieving all the advantages of overhead-valve engines without the cost. This new type of engine, known as the turbulent head, was patented in 1932. The company went on to design a 6-cylinder diesel engine producing 130 brake horsepower (97 kW) which was manufactured by AEC for use in London bus fleets. This type of engine, branded as The Comet, was taken up by Berliet and Citroën of France, MAN of Germany, and Fiat and Breda of Italy, among others.
In the 1930s, the company undertook work to convert a Kestrel V12 to diesel operation using single sleeve valve technology: Captain George Eyston used the new engine in the Flying Spray, which, at 159 miles per hour (256 km/h), broke the world diesel speed record at Bonneville in May 1936.
Also in the 1930s, Sir Henry Tizard, Chairman of the Aeronautical Research Committee, who was a proponent of a high-powered "sprint" engine for fighter aircraft and who had foreseen the need for such a powerplant with the threat of German air power looming, encouraged Ricardo to develop what eventually became the Rolls-Royce Crecy engine. In 1931, Harry Ricardo gave a lecture to the Royal Society of Arts, in which he invited his audience to "accompany me inside the cylinder of a diesel engine", passionately describing the process of diesel combustion, in great detail.
In 1938, the company developed the V-16 engine for the Alfa Romeo Tipo 162, a car with highly streamlined bodywork. In 1941, the company developed a relief valve subsequently named "Barostat", which automatically reduced the pressure in the fuel lines as the aircraft gained altitude, thereby avoiding the risk of the engine overspeeding: the Gloster E.28/39, designed by Frank Whittle, used this device.

### Post-war

In the 1950s, the company worked with the railway locomotive designer, Lieutenant Colonel Louis Frederick Rudston Fell, to develop an engine for the 4-8-4 Fell locomotive. The United States Navy placed a contract with the company, in 1968, to develop a diesel power unit capable of running for extended periods at ocean depths of up to 600 feet (180 m); the concept was known as "recycle diesel" and involved blending a proportion of exhaust gas with fresh oxygen.
In the 1970s, Opel used Ricardo combustion-chamber technology for the Opel 2100D engine which was installed in the Opel Rekord Series D. General Motors used the same technology in the Chevrolet Suburban in the 1980s. In 1990, the company undertook the development of an automatic layshaft transmission as part of an integrated power-train control system. Then, in 1994, the company acquired a major developer of four-wheel drive technology, FF Developments; this business formed the basis of the company's driveline operations in the UK.
In the early 21st century, the company undertook work to improve the BMW K1200 series motorcycle engines which were subsequently fitted to the BMW Motorrad K1300S, K1300GT and K1300R models. In August 2006, Wing Commander Andy Green successfully achieved a new diesel speed record of 350.092 miles per hour (563.418 km/h) at Bonneville Salt Flats in Utah, in the JCB Dieselmax with the aid of a diesel engine designed with Ricardo combustion-chamber technology.
The company went on, in around 2008, to develop an engine capable of switching between two-stroke and four-stroke cycles in collaboration with Denso, Jaguar Land Rover and the Centre for Automotive Engineering at the University of Brighton: it was claimed that the engine could improve fuel economy by up to 25%. The company collaborated with Xtrac by assisting with some parts manufacture for the 1044 gearbox, supplied in 2010 to three Formula One teams: Lotus, Virgin and HRT. This gearbox was mated to the Cosworth CA2010 engine.
In 2009, McLaren Automotive selected Ricardo to develop a new engine, a 3.8 litre twin-turbo V8, which became known as the McLaren M838T, for its supercars. At around the same time, the company working in collaboration with Israel Aerospace Industries, developed a semi-robotic tug, Taxibot, which clamped around the aircraft's nosewheel and was controlled remotely by the pilot; the product was intended to reduce aviation fuel consumption.
The Ministry of Defence selected a vehicle developed by Ricardo and Force Protection, known as Ocelot, to replace the Snatch Land Rover in 2010.
In 2011, Ricardo developed a carbon-fibre flywheel with a magnetic coupling and gearing system for energy-storage purposes: the product was known as "TorqStor".
In April 2015, the company acquired Lloyd's Register Rail for £42.5 million, with the intention of developing the company's rail expertise.