Leslie George Frise FRAeS (2 July 1895 – 26 September 1979) was a British aerospace engineer and aircraft designer; he designed the Type 156

Bristol Beaufighter The Bristol Type 156 Beaufighter (often called the Beau) is a British multi-role aircraft developed during the Second World War by the Bristol Aeroplane Company. It was originally conceived as a heavy fighter variant of the Bristol Beaufort ...

. He was involved in the development of aircraft and gun-turret hydraulic systems.

Early life

Frise was born in Bristol,

Gloucestershire Gloucestershire ( abbreviated Glos) is a county in South West England. The county comprises part of the Cotswold Hills, part of the flat fertile valley of the River Severn and the entire Forest of Dean. The county town is the city of Gl ...

, an area which is now known as

South Gloucestershire South Gloucestershire is a unitary authority area in the ceremonial county of Gloucestershire, South West England. Towns in the area include Yate, Chipping Sodbury, Thornbury, Filton, Patchway and Bradley Stoke, the latter three forming part ...

. He was educated at

Bristol Grammar School Bristol Grammar School (BGS) is a 4–18 mixed, independent day school in Bristol, England. It was founded in 1532 by Royal Charter for the teaching of 'good manners and literature', endowed by wealthy Bristol merchants Robert and Nicholas Thorn ...

and gained a BSc degree in Mechanical Engineering from the

University of Bristol , mottoeng = earningpromotes one's innate power (from Horace, ''Ode 4.4'') , established = 1595 – Merchant Venturers School1876 – University College, Bristol1909 – received royal charter , type ...

. Early in First World War he served in the

Royal Naval Air Service The Royal Naval Air Service (RNAS) was the air arm of the Royal Navy, under the direction of the Admiralty's Air Department, and existed formally from 1 July 1914 to 1 April 1918, when it was merged with the British Army's Royal Flying Corps t ...

(RNAS).

Boulton Paul Aircraft

In 1915 he started Boulton Paul Aircraft's first aircraft factory at

Mousehold Heath Mousehold Heath is a freely accessible area of heathland and woodland which lies to the north-east of the medieval city boundary of Norwich, in eastern England. The name also refers to the much larger area of open heath that once extended f ...

, Norwich to make 100

Sopwith Camels The Sopwith Camel is a British First World War single-seat biplane fighter aircraft that was introduced on the Western Front in 1917. It was developed by the Sopwith Aviation Company as a successor to the Sopwith Pup and became one of the be ...

. The company was previously a general manufacturing firm that had begun in 1873.

Bristol Aeroplane Company

In August 1915,

Frank Barnwell Captain Frank Sowter Barnwell OBE AFC FRAeS BSc (23 November 1880 – 2 August 1938) was a Scottish aeronautical engineer. With his elder brother Harold, he built the first successful powered aircraft made in Scotland and later went on to a c ...

rejoined Bristol Aeroplane Company and was looking for an assistant. He interviewed Leslie Frise and employed him in 1916; Frank Barnwell would become one of Bristol's main aircraft designers until his death on 2 August 1938 in an aviation accident. Barnwell developed the 1916

Bristol F.2 Fighter The Bristol F.2 Fighter is a British First World War two-seat biplane fighter and reconnaissance aircraft developed by Frank Barnwell at the Bristol Aeroplane Company. It is often simply called the Bristol Fighter, ''"Brisfit"'' or ''"Bif ...

with Frise's assistance. He invented the

Frise aileron An aileron (French for "little wing" or "fin") is a hinged flight control surface usually forming part of the trailing edge of each wing of a fixed-wing aircraft. Ailerons are used in pairs to control the aircraft in roll (or movement around ...

, also known as the slotted aileron, in 1921, which is designed to counteract

adverse yaw Adverse yaw is the natural and undesirable tendency for an aircraft to yaw in the opposite direction of a roll. It is caused by the difference in lift and drag of each wing. The effect can be greatly minimized with ailerons deliberately designed to ...

, which won him the

Royal Aeronautical Society The Royal Aeronautical Society, also known as the RAeS, is a British multi-disciplinary professional institution dedicated to the global aerospace community. Founded in 1866, it is the oldest aeronautical society in the world. Members, Fellows ...

's Wakefield Gold Medal (for advances in aviation safety) awarded on 30 May 1933. The Frise aileron has an effect on

parasitic drag Parasitic drag, also known as profile drag, is a type of aerodynamic drag that acts on any object when the object is moving through a fluid. Parasitic drag is a combination of form drag and skin friction drag. It affects all objects regardless of ...

so that the total drag on both wings is the same when an aircraft executes a

roll Roll or Rolls may refer to: Movement about the longitudinal axis * Roll angle (or roll rotation), one of the 3 angular degrees of freedom of any stiff body (for example a vehicle), describing motion about the longitudinal axis ** Roll (aviation), ...

. In 1934 he developed, with Frank Barnwell, the

Bristol Type 143 The Bristol Type 143 was a British twin-engine monoplane aircraft designed by Frank Barnwell of the Bristol Aeroplane Company. Developed alongside the more famous Bristol Type 142, which was developed into the Blenheim light bomber, it used th ...

, a monoplane with

retractable undercarriage Landing gear is the undercarriage of an aircraft or spacecraft that is used for takeoff or landing. For aircraft it is generally needed for both. It was also formerly called ''alighting gear'' by some manufacturers, such as the Glenn L. Martin ...

; only one prototype was made. In 1936, when Barnwell became chief engineer, Frise became chief designer. He worked for 32 years for Bristol retiring, as chief engineer, in 1946 on grounds of ill health.

Percival Aircraft

Frise joined Percival Aircraft in 1948 as technical director and chief engineer. He designed a naval version of the

Percival Prince The Percival Prince is a British light transport of the early postwar period. It was a twin-engine, high-wing, cantilever monoplane of all-metal stressed-skin construction; the undercarriage was of retractable, tricycle type. Development ...

and the Percival Sea Prince. He also designed the

Percival Provost The Percival P.56 Provost is a basic trainer aircraft that was designed and manufactured by British aviation company Percival. During the 1950s, the Provost was developed for the Royal Air Force (RAF) as a replacement for the Percival Prentic ...

basic trainer and a jet-powered version the

Jet Provost The BAC Jet Provost is a British jet trainer aircraft that was in use with the Royal Air Force (RAF) from 1955 to 1993. It was originally developed by Hunting Percival from the earlier piston engine-powered Percival Provost basic trainer, an ...

. In 1956 he left to become Director of Special Projects with

Blackburn Aircraft Blackburn () is an industrial town and the administrative centre of the Blackburn with Darwen borough in Lancashire, England. The town is north of the West Pennine Moors on the southern edge of the Ribble Valley, east of Preston and north- ...

Aircraft designed

Frise was involved in the design of or lead the design team as chief engineer for the following aircraft: *

Bristol Beaufort The Bristol Beaufort (manufacturer designation Type 152) is a British twin-engined torpedo bomber designed by the Bristol Aeroplane Company, and developed from experience gained designing and building the earlier Blenheim light bomber. At l ...

Bristol Blenheim The Bristol Blenheim is a British light bomber aircraft designed and built by the Bristol Aeroplane Company (Bristol) which was used extensively in the first two years of the Second World War, with examples still being used as trainers until ...

Bristol Brabazon The Bristol Type 167 Brabazon was a large British piston-engined propeller-driven airliner designed by the Bristol Aeroplane Company to fly transatlantic routes between the UK and the United States. The type was named ''Brabazon'' after th ...

Bristol Brigand The Bristol Brigand was a British anti-shipping/ground attack/dive bomber aircraft, developed by the Bristol Aeroplane Company as a replacement for the Beaufighter. A total of 147 were built and were used by the Royal Air Force in Malaya duri ...

Bristol Bulldog The Bristol Bulldog is a British Royal Air Force single-seat biplane fighter designed during the 1920s by the Bristol Aeroplane Company. More than 400 Bulldogs were produced for the RAF and overseas customers, and it was one of the most fa ...

Bristol Freighter The Bristol Type 170 Freighter is a British twin-engine aircraft designed and built by the Bristol Aeroplane Company as both a freighter and airliner. Its best known use was as an air ferry to carry cars and their passengers over relatively s ...

* Hunting-Percival Jet Provost *

* Percival Sea Prince

Personal life

Frise married in 1922 in Bristol; they had a son born in 1938 and a daughter in 1948. He died in Bristol aged 84.

Honours and awards

Frise was admitted to the

Freedom of the City of London The Freedom of the City of London started around 1237 as the status of a 'free man' or 'citizen', protected by the charter of the City of London and not under the jurisdiction of a feudal lord. In the Middle Ages, this developed into a freedom or ...

in 1948.

References

External links

Biography

Aviation Archive
{{DEFAULTSORT:Frise, Leslie 1895 births 1979 deaths Aircraft designers Alumni of the University of Bristol Aviation pioneers Bristol Aeroplane Company British World War I pilots English aerospace engineers Fellows of the Royal Aeronautical Society People educated at Bristol Grammar School Engineers from Bristol Royal Naval Air Service aviators