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W. O. Bentley
Born 16 September 1888(1888-09-16)
Hampstead, England
Died 13 August 1971 (aged 82)
Woking, England

Walter Owen Bentley, MBE (16 September 1888 – 13 August 1971[1]) was an English engineer; designer of aero engines, designer and racer of motor cars, founder of Bentley Motors Limited in Cricklewood near London.

He was known as "W. O." without any need to add the word Bentley.[note 1]

Early life

Bentley symbol

Bentley was born in Hampstead, London the youngest of nine children of his Adelaide-born[2] parents: retired businessman Alfred Bentley and Emily née Waterhouse.[3] The son of a prosperous Hampstead, London, family he was educated at (then) public school, Clifton College, Bristol from 1902 until 1905 which he left at the age of 16 to start work as an apprentice railway engineer with the Great Northern Railway at Doncaster in Yorkshire. "The sight of one of Patrick Stirling's eight-foot singles could move me profoundly."[4] At Doncaster he learnt, hands-on, each technical procedure; how to cast, make and build complex machinery as well as design it.


G N R Atlantic express locomotive No. 251

This premium apprenticeship cost his father £75 for a five-year term[5] but with Great Northern he came close to his childhood ambition of driving a Great Northern Atlantic express locomotive. At the end of his apprenticeship he was made—for footplate experience—a second fireman on main-line expresses.[6] "My longest day was London to Leeds and back, on the return journey doing Wakefield to King's Cross non-stop for 175 miles. This was a total day's run of 400 miles, entailing a consumption of about seven tons of coal, every pound of it to be shovelled. Not a bad day's exercise."[4] During this time he also experimented with motorcycles, riding and racing Quadrant, Rex, and Indian models. He completed his apprenticeship in the summer of 1910 and decided that for him the railways did not hold enough scope for a satisfying career.

He spent a brief period studying theoretical engineering at King's College London, and a period with the National Motor Cab Company then running a fleet of 250 Unics where he was, amongst other things, in charge of cab maintenance and fascinated by the cabbies' ingenuity at fiddling the meters.

In 1912 he joined his brother, H. M. (Horace Millner) Bentley, in a company called "Bentley and Bentley" selling French DFP cars. Convinced that successful participation in competition was the best way to market these cars and dissatisfied with their performance, W. O.—inspired by a paperweight—had a set of aluminium alloy pistons made for the DFP engine and with a tuned camshaft, took several records at Brooklands in 1913 and 1914.

Aero engines

Bentley BR2 rotary engine

At the outbreak of war W. O. realised his idea of using aluminium alloy pistons should be put to use in the national interest. It considerably improved power output. The pistons ran cooler allowing higher compression ratios and higher engine speeds. Security ruled out broadcasting the knowledge amongst engine manufacturers. After some weeks he managed to make contact with the official liaison between the Navy and those manufacturers. That man, Commander Wilfred Briggs, became his senior officer for the rest of the war.[4]

W. O. was immediately given a commission in the Royal Naval Air Service and sent to tell the manufacturers—the first was the future Lord Hives at Rolls-Royce of his knowledge and experience having had the manufacturers modify their DFP car engines which Bentley sold in Britain. So Rolls-Royce's first aero-engine, Eagle, had aluminium instead of cast-iron or steel pistons. From Derby he went to Wolverhampton to Louis Coatalen at Sunbeam and the same idea was used in all the Sunbeam aero-engines. W. O. was then sent to the Gwynnes Limited, Chiswick factory making French Clerget engines under licence and liaised between the squadrons in the field in France and the Chiswick factory's engineering staff.[4]

The Clerget licensees were very unwilling to act on his more important suggestions so the Navy sent W. O. to Coventry to Humbers where he was given a team to design his own aero-engine. The resulting engine, fundamentally different from the Clerget though—for ease of production—alike in the design of the cam mechanism, was running in prototype by early summer 1916. This was the BR1, Bentley Rotary 1. The bigger BR2 followed in early 1918. The success of these engines may be read about in their own articles.[4]

For this work W. O. was awarded an MBE. In 1920 he was invited to make a claim—which was unsuccessfully contested by the Clerget licensees—and was later awarded £8,000 from the Royal Commission on Awards to Inventors.[4]

Bentley Motors, Cricklewood, Middlesex

1923 Bentley 3-litre

After the war, in early 1919, W. O. founded, with his brother,[7] their own motor car business, Bentley Motors Limited. The first Bentley 3-litre engine burst into life in what was New Street Mews, Baker Street, London, in October 1919. A plaque marks the building in now Chagford Street NW1. The first complete car began road testing in January 1920. W. O. had designed a robust four-cylinder engine and sturdy chassis, the Bentley 3 Litre. The first production car, made in small premises in Cricklewood, was delivered in September 1921. Its durability earned widespread acclaim.

Appearances were made in hill climbs and at Brooklands and a single entry in the 1922 Indianapolis 500 mile race driven by Douglas Hawkes finished thirteenth at an average speed in excess of 80 miles an hour. A rather sceptical Bentley had been persuaded to attend the very first, 1923, Le Mans race. To his great delight the privately entered Bentley of Duff & Clement took fourth place.[6]

The 3 Litre won the 24 hours of Le Mans in 1924 and following models repeated this each June 1927, 1928, 1929, and 1930. His motto was, "To build a good car, a fast car, the best in class." His racing manager was an old school friend, Richard Sidney Witchell. Bentley cars set many records at Le Mans. "Bentley Boy" Woolf Barnato was the only driver to win each of the three times he entered, giving him the highest victory percentage.

However, the 1925 Le Mans race was a complete failure for W. O. and his team, and Bentley Motors Limited was in deep financial trouble. His actions were severely criticised by his board. The temporary solution was that Woolf (Babe) Barnato, of the "Bentley Boys", heir to Kimberley diamond magnate Barney Barnato purchased all the business assets and they continued much as before with Barnato chairman[6] but W. O. was now Barnato's employee.

Speed Six

W. O. designed another generation of cars, the six-cylinder 6+12-litre Speed-Six introduced 1928, but in 1929 against his wishes, Barnato allowed to be built before development was complete the Tim Birkin developed supercharged "Blower" version of his 1927 4½ Litre car. This development had taken place in separate workshops away from W. O. in Welwyn Garden City.[7] Durability proved poor and the car failed on the track. At the time, Ettore Bugatti commenting upon the Bentley line of motorcars quipped with a certain disdain, "Mr. Bentley builds the worlds' fastest trucks." Barnato continued to compete with distinction and helped steer the firm to its finest hour, but everyone's efforts did not save the business. The Great Depression delivered the final financial blow. The 8 Litre was launched as a grand car for the ultra-rich in October 1930. One hundred were made and sold. Ettore Bugatti sold three of his equivalent model. The 8 Litre's very success proved disastrous for W. O. 's own career. Rolls-Royce (Hives) elected to kill such strong competition for their Phantom II.

By July 1931, Barnato had decided he would provide no more support for the company and made himself scarce. On the 10th, on the application of the mortgagee, the court appointed a Receiver to Bentley Motors Limited.[8] W. O.'s cars had accumulated losses of £136,220. With Barnato's they were working their way through their third fortune.[9]

D. Napier and Son had manufactured cars in England until 1925, when they had shifted focus to aero engines; they were now anxious to return to the motor car market and entered friendly negotiations to purchase Bentley, and W. O. began work designing his next car for the expected new owner, Napier-Bentley. Rolls-Royce watched with care.

The Press Association understands that Messrs Napier and Son, aero-engine builders, have reached an agreement to take over Bentley Motors Limited which is in voluntary liquidation. It is expected that the matter will come before the Court within the next few days.

Press Association, Napier To Absorb Bentley Motors, The Times, Saturday, Oct 24, 1931; pg. 18; Issue 45962

Cricklewood production[4][10]

Dr Benjafield's 3-litre

Bentley 8-litre saloon

Year 3-litre 4-litre 4+12-litre 6+12-litre 8-litre Total
  • 506 of the 3-litre cars were 'Speed Models' and 15 '100 mph Models'
  • 54 of the 4+12-litre cars were supercharged
  • 171 of the short-chassis 6+12-litre cars were 'Speed Sixes'
See also: List of surviving pre war Bentley cars

Rolls-Royce Limited, Derby

At the very last minute arch-rival Rolls-Royce topped Napier's bid, announcing their acquisition of Bentley on 20 November 1931. Rolls-Royce had been disturbed by the 8 Litre's encroachment upon the market segment of their Phantom II. The old business had not troubled to register their Bentley trademark. Rolls-Royce took immediate steps to remedy that.[11] Cricklewood was closed during 1932. Thereafter production was from Rolls-Royce premises in Derby and, postwar, Crewe.

Rolls-Royce had acquired the Bentley showrooms in Cork Street, the service station at Kingsbury, the whole establishment at Cricklewood and Bentley himself. This last was disputed by Napier in court without success. Everything was sold but some 8-litre chassis which were taken to Derby. The name alone was to be kept and used for a smaller economy car but that prototype proved to be as complex and expensive as the bigger Rolls-Royces and its development was halted.[4]

W. O. believed Barnato had bought a substantial shareholding in Rolls-Royce just before pulling out his support while visiting New York. Barnato was invited to become a director of the new Rolls-Royce subsidiary, Bentley Motors (1931) Limited.[4]

W. O.'s winter of 1931/1932 was hard, his wife divorced him and he lost any form of personal transport. Hearing of this W. E. Rootes arranged for him to test a new Hillman each weekend.


As obliged to do by the court he joined Rolls-Royce under a contract extending from 1 May 1932 to the end of April 1935.[11][12] Rolls-Royce isolated him in London and Europe, keeping him occupied as liaison between customers and—at long range—the works, to test drive vehicles at Brooklands and for long test runs across the Continent and the Alps.[4]

While he worked on testing the prototype he was only permitted to comment on the design of what would become the new Derby 3+12-litre announced in October 1933.[13] Around that time he managed to begin to report in person to the design teams at Derby making friends in the process. Among them Harry Grylls and Stewart Tresilian who did some design-only work on a short-stroke replacement for the V12 engine for their Phantom III. W. O. had been effectively sequestered from the design team of the new car bearing his own name. But, he did admire their achievement.[4]

Rolls-Royce promoted its new line of Bentleys as "The Silent Sports Car".[14] W. O. left Rolls-Royce at the end of April 1935 with a sense of freedom.[15]

Lagonda, Staines, Middlesex

Lagonda M45 Tourer (Logo), Bj. 1933 (2009-08-07).jpg

A Lagonda M45R Rapide with a Meadows engine won at Le Mans in June 1935. Just a week later Lagonda was pronounced saved from receivership by Alan P Good[16] and W. O. joined Good's new Lagonda board of directors as technical director. W. O. moved, with the majority of the Rolls-Royce racing department staff, to Lagonda. There, W. O. again went racing. Unable to persuade Harry Grylls to join his engineering staff at Staines W. O. did obtain Stewart Tresilian's services from February 1936. Tresilian brought Frank Stark and Reg Ingham with him. Donald Bastow joined them.

U S advertising 1937

W. O. made Tresilian chief designer of the V12 project. The masterpiece V12 was launched in 1937. The 4480 cc engine delivered 180 bhp;hp (134 kW) and was said to be capable of going from 7 to 105 mph in top gear and to rev to 5000 rpm. Tresilian left in early 1938 for a Hawker Siddeley subsidiary.[11] V12 development was not complete but Lagonda's difficult financial circumstances encouraged more to leave at that time. The car was exhibited at the 1939 New York Motor Show: "The highest price car in the show this year is tagged $8,900. It is a Lagonda, known as the "Rapide" model, imported from England. The power plant is a twelve-cylinder V engine developing 200 horsepower."[17]

During the war W. O. worked on armaments at Lagonda.[6] Towards the end of the war he began work on a new straight-6 engine. It was clear Lagonda's V12 would be seen as too extravagant for the postwar market. With his team he developed a modern dual overhead cam straight-6 engine. It initially displaced 2.6 L (2580 cc/157 in3) with a 78 mm (3.07 in) bore and 90 mm (3.543 in) stroke it produced roughly 105 hp (78 kW) with dual SU carburettors. It was not to get on to the market until 1948.

In August 1947 J. R. Greenwood, chairman of Lagonda, announced though work had begun on the first 1,000 of its new 2+12-litre motorcar designed by Mr W. O. Bentley, due to shortage of materials,[note 2] continuing difficulties of production and the recently imposed double purchase tax those plans had been cancelled. While there were other engineering activities including the manufacture of a diesel pile-driver it had informed the 1,600 workpeople involved that some of them would inevitably become redundant.[18]

David Brown, Feltham, Middlesex

A month later, in mid-September it was announced that the Lagonda specification had been bought by David Brown & Sons (Huddersfield) Limited, gear-wheel manufacturer, which would combine production with Aston Martin bought earlier that year.[19]

Production was moved to Feltham, Middlesex.

Brown had purchased Lagonda largely to gain Bentley's engineering expertise, and immediately placed W. O. 's newest creation, his 2.6-litre Lagonda Straight-6 engine, under the bonnet of Brown's other new acquisition, the Frank Feeley-designed DB2. This durable DOHC engine would continue in Lagondas and Aston Martins until 1959 and, W. O. noted, important design details were carried on through to their V8.

Armstrong Siddeley

W. O. remained as an engineer at Aston Martin-Lagonda for a time, then he moved to Armstrong Siddeley, where he designed another twin-overhead-cam 3-litre engine before retiring.
However it is reported[20] that W. O. 's team's, it included Donald Bastow, responsibilities for the Sapphire project which also extended to the chassis, ceased in 1949 and as it eventuated they provided not a lot more than the detailed inspiration for the production version of the Sapphire announced in October 1952. The production cost of W. O. 's exact engine design was considered to be too high. Nevertheless W. O. 's involvement maintained the considerable respect of contemporary engine designers and manufacturers for him and the final Sapphire product.

Personal life

W. O. married three times. In 1914 he married Leonie Gore, the daughter of the ninth baronet,[3] she died in 1919 in the Spanish flu epidemic. He married Poppy (Audrey Hutchinson) in 1920, they divorced soon after the business was sold in 1931. He married Margaret Roberts Hutton née Murray in 1934 and she survived him. He had no children.

Bentley died at Woking, Surrey, Friday 13 August 1971, shortly before his 83rd birthday, revered patron of The Bentley Drivers' Club. His widow, Margaret, survived him and died in 1989.


Following his lengthy obituary printed in The TImes 16 August 1971 the same newspaper printed two more contributions.

" . . . In the eyes of those who own, have owned, or aspire to own, one of the 3,040 Bentley cars designed and built by the 'old' Bentley company under the leadership of "W. O." he was admired and respected—indeed, I think, loved is not too strong a word—for to know his cars was to know him. During his working life "W. O." suffered a series of ups and downs which might have broken a lesser man. It certainly marked him and it was a disillusioned "W. O." I first met 25 years ago [1946]. . . . "W. O." has said that the pleasure he derived in the post-war years from Club activities; from making new friends among its members; and from seeing the loving care bestowed upon 'his' cars has more than compensated for all his earlier disappointments." S. S.[21]

"The six years during which I worked for "W. O." were a period of education and pleasure. His modesty, lack of pretension, mental honesty and reasonableness endeared him to those in contact with him, and his over-riding interest in the improvement of the car provided the education in a period which included the post-war 2+12-litre Lagonda development, schemes for 4 and 8 cylinder derivatives, for the pursuit of shorter strokes in engines, for a small transverse-engined front wheel drive car and for a performance engine for the Morris Minor in place of the 850cc side valve engine it then endured.
Though normally of reflective habit his experience showed him when swift action was necessary, and he could be very determined in pursuing it. Big enough to admit mistakes when they had occurred, he also knew when to modify and when to start afresh in remedying them.
It is a pity that circumstances prevented his influence on car development from being greater than it was. Though motoring and motor cars were his life he retained a keen interest in locomotives." Mr Donald Bastow.[22]

The Bentley Drivers' Club

Woolf Barnato (1895–1948) served a term as president. W. O. agreed to become patron in 1947.
Founded in 1936 this club now has nearly 4,000 members throughout the United Kingdom, Europe, US, Canada, Southern Africa, Australia, New Zealand and Japan.


  1. The convention of the day required that individuals be addressed by their surname prefixed by Miss, Master, Mrs or Mr. To do otherwise indicated a degree of familiarity or implied superiority which might not be welcome to either party. To distinguish by adding just the Christian name might also indicate a level of familiarity. There were further refinements.
    To differentiate between brothers who worked together it was conventional to use initials rather than the slightly more familiar Christian names. Hence Mr W. O. Bentley working with Mr H. M. Bentley led to the short form of reference to each of them: W. O. and H M.
  2. The Ministry of Supply's wartime controls over the allocation of steel supplies remained in force from 1945 to 1954. These controls were designed to try to at least maintain supply to existing consumers but it is since acknowledged they were applied in a highly discriminatory fashion. Lagonda had tooled up for quantity production and provided evidence of a substantial export orderbook.
    They were allocated steel for just 100 cars.
    David Brown's companies were able to obtain the necessary steel.
    One well-known side-effect of these controls was that Land-Rovers contained a great deal of aluminium and won an unintended reputation for not rusting.


  1. Deaths, The Times, Monday, 16 August 1971; pg. 20; Issue 58251
  2. UK Census 1911, 80 Avenue Road, Hampstead. RG14PN616 RG78PN22 RD8 SD1 ED26 SN260
  3. 3.0 3.1 H. G. Pitt, ‘Bentley, Walter Owen (1888–1971)’, rev. Oxford Dictionary of National Biography, Oxford University Press, 2004 ; May 2006
  4. 4.00 4.01 4.02 4.03 4.04 4.05 4.06 4.07 4.08 4.09 4.10 W. O. Bentley My Life and My Cars, 1967, London, Hutchinson & Co
  5. Bentley Drivers Club Early Years
  6. 6.0 6.1 6.2 6.3 Obituary, The Times, Saturday, 14 August 1971; pg. 14; Issue 58250
  7. 7.0 7.1 Bentley Drivers Club Vintage History
  8. Receiver Appointed of Bentley Motors Limited Re Bentley Motors Limited; London Life Association Limited v. Bentley Motors Limited, And Woolf Barnato. The Times, Saturday, 11 July 1931; pg. 4; Issue 45872
  9. Graham Robson, 60 years of Bentley, Thoroughbred and Classic Cars, September 1979
  10. W. O. Bentley, An Illustrated History of the Bentley Car 1919–1931 1964, London, George Allen and Unwin Limited
  11. 11.0 11.1 11.2 "The court case against Lagonda and W. O. Bentley". Retrieved on 2013-03-18.
  12. Bentley Motors (1931) Limited v. Lagonda Limited and Walker Owen Bentley and in re Bentley (1931) Limited's Trade Mark No 528,124. Reports of Patent Design and Trade Mark Cases Vol LXIV No.2
  13. Cars of 1934 The New Bentley The Times, Tuesday, 3 October 1933; pg. 6; Issue 46565
  14. Feast, Richard (2004). "Chapter 5: Togetherness: Rolls-Royce/Bentley", The DNA of Bentley. St. Paul MN USA: MotorBooks International, 77. ISBN 978-0-7603-1946-8. Retrieved on 2013-03-21. “In the end, Rolls-Royce made a virtue of the feature by successfully promoting the 3 1/2 as the Silent Sports Car.” 
  15. Feast, Richard (2004). "Chapter 4: When Barnato bought Bentley", The DNA of Bentley. St. Paul MN USA: MotorBooks International, 69. ISBN 978-0-7603-1946-8. Retrieved on 2013-03-21. “In addition to returning to car design and development, it meant liberation from the politics and anxieties of Rolls-Royce. He afterwards recalled that he felt 'quite light-headed with the sense of freedom'.” 
  16. Sale of Lagonda The Times, Monday, 24 June 1935; pg. 22; Issue 47098
  17. New York Times, 17 October 1939, Page 16.
  18. New Car Cancelled Lagonda Company Decision The Times, 11 August 1947; pg. 3; Issue 50836
  19. The New Lagonda Car Export Possibilities The Times, 20 September 1947; pg. 3 & pg. 7; Issue 50871
  20. Hodgson, Richard (2000). "Obituary: John R. Densham". Retrieved on 2013-03-18.
  21. Mr W. O. Bentley The Times, 17 August 1971; pg. 12; Issue 58252
  22. Mr W. O. Bentley The Times, 21 August 1971; pg. 12; Issue 58256
  • Bobbitt, Malcolm (2003). Bentley: The Man behind the Marque. Derby, United Kingdom: Breedon Books. ISBN 1-85983-352-7. 
  • Bentley, W. O. (1969). My Life and My Cars. Cranbury, New Jersey: A.S. Barnes. ISBN 0-498-07342-4. 

Material gathered from the last two references detailed above has been augmented by information from newspaper reports and other sources here marked by inline citations.

External links

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