Folland 43/37 P1775, the second example, in its second configuration with a Centaurus IV and four-blade propeller in the nose. Note the 'plug' between the 'designed' firewall and the engine for centre of gravity purposes

The third 43/37, P1776, with its Sabre I (Sabre II ???) partially uncowled, February 1941. Construction used as much wood as possible and the contract actually noted that the airframes were to be received by the Directorate of Technical Development without engines. P1776 was written off in a flying accident on August 28, 1944.

Believed unique in having a Rolls-Royce Griffon installation, the fifth 43/37, P1778, was last used by Rolls-Royce and de Havilland Propellers. Note its very worn appearance.

1940-е годы - испытания британских поршневых двигателей. Folland Fo 108 строился специально для испытаний двигателей. Разработанный в соответствии с техническим заданием 43/37, Fo 108 имел экипаж из трех человек, а первая из 12 заказанных машин была поставлена в 1940 году. На машине испытывали различные типы силовых установок, включая Bristol Centaurus и Napier Sabre (на снимке).
It was Gloster test-pilot Neil 'Mike' Daunt who coined the name 'Frightful' for the first Folland design to see production. Folland tendered the Fo 108 form and won, Specification 43/37 (OR.55). This was a requirement for 12 engine test-beds, to take powerplants in the 1,500 to 2,000hp (1,119 to l,492kW). As well as the pilot, two observers and their equipment were to be accommodated within the commodious fuselage. Dispersed from their Hamble, Hants, base, the 43/37s were assembled in the Cheltenham area and flight-tested at Staverton, Glos. Hence the 'pinching' of Gloster test-pilots Gerry Sayer and 'Mike Daunt'. Illustrated is the first example, P1774 in August 1941 with a Napier Sabre III (2,100-h.p. Napier Sabre I ???).

Not directly linked to the Fo 108, but clearly showing the same family traits, was the Fo 116. Two of these bulky, fixed undercarriage, beasts were ordered against Specification E28/40 (OR.101) of February 1941 for an aircraft to carry deck-landing experiments at high weights. The specification also called for the type to have the ability to undertake reconnaissance, torpedo attack and dive-bombing sorties. The wing on the Fo 116 was variable incidence, moving from 4 to 15 degrees. Construction of two Centaurus III-powered examples (DX160 and DX165) was commenced at Cheltenham, but abandoned.