On 12 March 1928, one S.5 fatally crashed during an attempt on the world air speed record, killing the pilot Flight Lieutenant Samuel Kinkead.

[3] Furthermore, the resulting aircraft possessed numerous unorthodox features, some of which were developed to meet specific conditions encountered during high speed air races.

[4] The forward section of the fuselage had particularly strong frames in order to appropriately support the wing roots, undercarriage struts and function as the attachment point for the anti-lift wire bracing.

They were almost entirely composed of duralumin, the centre section of the starboard float was made of steel to permit it to support the primary fuel tank.

[9] Instead, proven wooden construction was used for the wire-braced wings, which possessed spruce spars, spruce-ply ribs and a smooth plywood covering.

[7] Particular attention was paid to the oil system with the aim of minimising fractional losses in the propeller gearing and maximising the aircraft's speed potential.

The S.5s came 1st and 2nd in the 1927 Schneider Trophy race held at Venice; the winning aircraft (Serial number N220) was flown by Flight Lieutenant Sidney Webster at an average speed of 281.66 mph (453.29 km/h).

[1][2] One S.5, N221, crashed on 12 March 1928 during an attempt on the world air speed record, killing the pilot Flight Lieutenant Samuel Kinkead, who had flown the Gloster IV in the 1927 Schneider Trophy Race.

[citation needed] Data from Supermarine Aircraft since 1914,[19] National Advisory Committee for Aeronautics[20]General characteristics Performance Related development