The Boulton Paul P.29 Sidestrand was a twin-engine biplane medium bomber of the Royal Air Force.

Named after a village on the Norfolk coast near Boulton & Paul's factory in Norwich, the Sidestrand first flew in 1926 and entered service in 1928.

[1] Boulton & Paul Ltd of Norwich built a series of twin-engined biplanes starting with the Bourges of 1918, which although not ordered into production, had demonstrated excellent performance and manoeuvrability, followed by the 'all-metal' Bolton of 1922 and the smaller Bugle of 1923.

In 1924, the Air Ministry issued Specification 9/24 for an all-metal, twin-engined medium bomber, and Boulton & Paul's offering, designed by John Dudley North, led to an order for two prototypes early in 1925.

[4] The village of Sidestrand, chosen for the aircraft name, was the home of the Secretary of State for Air, Samuel Hoare.

The remaining twelve aircraft were powered by 460 hp (343 kW) Jupiter VIIIFs as the Sidestrand Mk III.

[1] Building on Boulton & Paul's experience with the Bourges, Bolton and Bugle, the airframe was carefully designed with the help of a wind tunnel to keep drag to a minimum.

Aluminium alloys were used for elements bearing lower structural loads, such as the outer interplane struts and wing ribs.

Production models incorporated a prominent Servo tab on the rudder and Frise ailerons to reduce pilot control loads.

[7] The Sidestrand inherited the good manoeuvrability of the Boulton Paul P. 7 Bourges, and put on a notably impressive display at the 1932 RAF Pageant.

101 Squadron operations record book that, "the Sidestrand [in formation] was a difficult proposition to tackle and that Fighters had no attack at present to meet them.