Frederick Charles Sigrist, was born on 20 May 1884 at Portsea Island, Hampshire, the eighth of eleven children of Edward Sigrist, a Col.Sgt in the R.M.A and Susannah Georgina Bentley. T.O.M. Sopwith once remarked that he doubted whether Sigrist had any schooling, but that did not prevent him from being an excellent mechanic.

In 1910 Sopwith and his friend V. W. Eyre became the owners of a 166-ton schooner called Neva and needed the help of a practical engineer. Someone recommended Sigrist, who worked at the Parsons Motor Company in Southampton. Bill Eyre engaged him and he was paid a salary of £2-14s (£2.70p) per week. Within a year they were immersed in the early days of flying and in December 1910, largely owing to Sigrist's genius in persuading those early engines to keep running, Sopwith was able to fly from Eastchurch to Belgium.

In 1911 Sopwith started the construction of aircraft, first in a shed at Brooklands and then in a disused skating rink at Kingston. Sigrist was placed in charge of the maintenance of the aeroplanes operated by the Sopwith School and was involved in the reconstruction of the Burgess Wright for instructional work. He became Works Manager and later General Manager to the Sopwith Aviation and Engineering Co., Ltd. His ideas, particularly those that simplified production, were incorporated in Sopwith designs and the line of famous rotary-engined fighting scouts can be traced back to his design, the "Sigrist Bus" that formed the subsequent basis for the 1-1/2 Strutter.

After the war, Sigrist took a well-earned rest, going to the USA in 1919 and spending some time in Los Angeles, California, but returned to the UK to become a founder member and joint Managing Director (with T.O.M. Sopwith) of the Hawker Engineering Co., Ltd. He stayed on the Hawker Board through various changes and when, in 1935, Hawker Siddeley Aircraft Co., Ltd. was formed, he became one of its first two joint managing directors. His organizational ability was demonstrated in his work with these companies, but he continued to develop innovations. With Sidney Camm, Sigrist used his knowledge of welding to develop the Hawker method of metal airframe construction that allowed such easy assembly and replacement of components in the classic designs of the 1920s and 1930s.

Outside of the Hawker Siddeley organisation, Sigrist was also associated with the formation of Reid and Sigrist in February 1928 for the development and manufacture of aircraft instrumentation, and in 1931, with Captain Henry Duncan Davis AFC, formed Brooklands Aviation Ltd., initially to manage Brooklands Aerodrome in Surrey.

Ill health seems to have plagued Sigrist through the '20s and '30; in early 1926 he was forced to take a month's leave in the south of France and in early 1934 took another two month cruise. By World War II Sigrist was beginning to show signs of being unable physically to stand up to British winters, and in April 1940 resigned from all his posts on medical advice and retired to build a house in Nassau in the Bahamas. Even then he still worked for the British Air Commission in California during much of the War.

Frederick Charles Sigrist, M.B.E., F.R.Ae.S., died on 10 December 1956 in Nassau, New Providence, Bahamas.