Napier & Son

Napier & Son was a British engine manufacturer and one of the most important aircraft engine manufacturers in the early to mid 20th Century. Their post-World War I Lion was the most powerful engine in the world for some time in the 1920s and into the 1930s, and their Sabre design of the early 1940s holds the title for the most powerful piston aircraft engine produced to this day, delivering 3,500 hp (2,600 kW) in its later versions.

Early History

David Napier founded the company in Soho, London in 1808, and made a wide variety of products including steam-powered printing presses and a centrifuge for sugar manufacturing. They moved to Lambeth, South London in 1830. After his father's death in 1873, his son James Napier specialised in beautifully-crafted precision machinery for making coins and printing stamps and banknotes.

His son Montague Napier inherited the business in 1895 and took on a job improving the Panhard car of his friend S F Edge. Edge was sufficiently impressed to encourage Napier to make his own car, agreeing to buy the entire output, and in 1900 the first one appeared. Napiers made the first ever production six cylinder car, many winning races including the 1902 Gordon Bennett race in France; famously, in the following year's Gordon Bennett Cup held in Ireland, a Napier was the first car to wear the green that would become British racing green. Production reached 250 cars in 1903, overwhelming the Lambeth factory so a move was made to Acton, West London. By 1907 1200 people were employed, there had been seven in 1895, making about 100 cars a year. In 1912 following a dispute with SF Edge, Napier bought Edge's distribution and sales company and production rose to around 700 cars a year with many supplied to the London Taxi trade.

Napiers expanded into marine engines as well, their 1905 boat Napier II setting the world water speed record for a mile at almost 30 knots (56 km/h).

World War I and Interbellum

Early in World War I, Napier was contracted to build engines from other companies' designs: initially a V12 Royal Aircraft Factory model and then Sunbeam Arabs. Both proved to be rather unreliable, and in 1916 Napier decided to design their own instead, an effort that led to the superb W-block 12-cylinder Lion. The Lion was a best-seller for the company, and they eventually abandoned all other products. The Lion went on to be used in the 1920s to win the World Land Speed Record in Malcolm Campbell's Bluebird and Henry Segrave's Golden Arrow.

Vehicle production continued and 2,000 trucks and ambulances were supplied to the War Office and in 1919 civilian car production re-commenced with a 6 L six cylinder car, the T75. These were very expensive, costing about the same as a Rolls-Royce Silver Ghost and in the early 1920s sales were falling. The last cars were made in 1924. An attempt was made to buy the bankrupt Bentley company in 1931 but Napier was outbid at the last minute by Rolls-Royce. The last vehicle project was a three wheeled tractor trailer goods vehicle, but rather than produce this themselves they sold it to Scammell who made several thousand.

In the 1930s the introduction of much larger and more powerful engines from other companies suddenly ended sales of the Lion. Napier quickly started work on newer designs, leading to the 16 cylinder Rapier and the 24 cylinder Dagger, both air-cooled H-block designs. Neither proved very reliable, due to poor cooling of the rearmost cylinders, and even the Dagger's 1,000 hp (750 kW) was already smaller than contemporary designs when it shipped.

Pre-and-World War II

Starting from scratch, the Napiers decided to use the new sleeve valve design in a much larger H-block 24-cylinder engine, soon to be known as the Sabre. The engine was very advanced and proved to be difficult to adapt to assembly line efforts, so while the engine was ready for production in 1940, it wasn't until 1944 that production versions were considered reliable. At that point efforts were made to improve it, leading eventually to the Sabre VII delivering 3,500 hp (2,600 kW), making it the most powerful engine in the world, from an engine much smaller than its competition.

Napier also worked on diesel aircraft engines. In the 1930s they licensed the Junkers Jumo 204 for production in England, which they called the Culverin. They also planned on producing a smaller version of the same basic design as the Cutlass, but work on both was cancelled at the outbreak of World War II.

Napier developed a marine engine from the Lion aero engine, the petrol-driven Sea Lion, which could deliver 500 hp and were used in the "Whaleback" Air Sea Rescue Launches.

During the war (1944) Napier were asked by the Royal Navy to supply a diesel engine for use in their patrol boats, but the Culverin's 720 hp (537 kW) was not nearly enough for their needs. Napier then designed the Deltic, essentially three Culverins arranged in a large triangle (deltoid). Considered one of the most complex engine designs of its day, the Deltic was nevertheless very reliable, and was taken into service after the war as a locomotive powerplant (in British Rail's Class 55) in addition to the torpedo boats, minesweepers and other small naval vessels for which it was designed.

Post-war

Last of the great Napier engines was the Nomad, a "turbo-compound" design that combined a diesel engine with a turbine to recover energy otherwise lost in the exhaust. The advantage to this "odd" design was fuel economy, it had the best specific fuel consumption of any aircraft engine built, even to this day. However even better fuel economy could be had by flying a normal jet engine at much higher altitudes, while existing designs filled the "low end" of the market fairly well. The Nomad was largely ignored by the market, and eventually cancelled.

Along with every other engine company in the post-war era, Napier turned to jet engine designs. Deciding to attack the only market not yet wrapped up by the larger vendors, Napier started the design of a number of turboprop designs which saw some use, notably in helicopters. Their first design, the Napier Naiad and Double Naiad were intended for various Royal Navy Fleet Air Arm designs, but saw no use in the end. Smaller models, the 3,000hp-class Napier Eland and 1,500hp-class Napier Gazelle did somewhat better, notably the Gazelle which powered several models of the popular Westland Wessex helicopter.

Napier was taken over by English Electric in 1942. Today Napier is no longer in the engine business, with the ending of the Deltic sales in the 1960s they had no new modern designs to offer. They continue on today as a primary supplier of turbochargers, which can be found on many engines.

External links

Deltic History: Napier Heritage