Boulton Paul Sidestrand
Sidestrand | |
---|---|
Role | Medium bomber |
Manufacturer | Boulton Paul
|
Designer | John Dudley North |
First flight | 1926 |
Introduction | 1928 |
Retired | 1936 |
Primary user | Royal Air Force |
Number built | 20 (four Sidestrands were converted into the Boulton Paul Overstrand) |
Variants | Boulton Paul Overstrand |
The Boulton Paul P.29 Sidestrand was a twin-engine
Design and development
Boulton & Paul Ltd of
The village of Sidestrand, chosen for the aircraft name, was the home of the
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. The fuselage was constructed from steel tube with a fabric and plywood covering. Aluminium alloys were used for elements bearing lower structural loads, such as the outer interplane struts and wing ribs.
The Sidestrand usually had a crew of three: pilot, nose gunner/bomb aimer and a rear gunner. Additionally, a navigator/co-pilot could be accommodated in a small cockpit immediately aft of the pilot's. There were three open gun positions; nose, dorsal and ventral. Armament for each position was a .303 in (7.7 mm) Lewis gun, the weapon being moved between the two rear positions depending on where each aircraft flew in a formation.[8] The bomb-load was limited to 1,050 pounds (480 kg), less than contemporaries such as the Tupolev TB-1.[9]
In the early 1930s a Sidestrand Mk III was fitted with Bristol Pegasus IM3 engines. This was intended to become the Sidestrand Mk IV, but eventually became the prototype for the redeveloped Boulton Paul Overstrand which would begin replacing the Sidestrand in service in 1936. Four Sidestrands were eventually converted to Overstrand standard and are essentially considered Overstrands.[9]
Operational history
Deliveries to the re-formed No. 101 Squadron began in 1928 at
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.[7] But despite proving to be an excellent aircraft for bombing and gunnery, only No. 101 Squadron was so equipped.
As part of its peacetime round of training duties, the Squadron undertook mock combat exercises with fighter squadrons and participated in the annual bombing competition (usually held at RAF Catfoss). After a mock combat exercise in the summer of 1930 with Armstrong Whitworth Siskin fighters of No. 111 Squadron, it was noted in the No. 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."[7]
The Squadron also experimented with 'glide bombing' (possibly dive bombing) in January 1932, and during 1934 the Sidestrand showed itself capable of intensive night flying.
Even with Jupiter VI engines, the aircraft could retain height on only one engine, turn in either direction and climb slowly (without bomb load).
The maximum endurance was found to be 6 hours with a 1/2 hour reserve. [7]
The Sidestrand never equipped any other squadrons and 101 Squadron remained essentially an experimental unit used by the RAF to test the medium day bomber concept.
Variants
- Sidestrand I
- Two prototypes.
- Sidestrand II
- Production variant, six built and converted to Sidestrand III.
- Sidestrand III
- Improved production variant, twelve built, four converted to Boulton Paul Overstrands.
- Sidestrand V
- Improved variant modified from a Mark III with more powerful engines, an enclosed cockpit and nose-mounted power-operated turret, renamed Boulton Paul Overstrand
Operators
Specifications (Mk III - performance with bomb load)
Data from The British Bomber since 1914.[10]
General characteristics
- Crew: three or four (pilot, two gunners and optional navigator/co-pilot)
- Length: 46 ft 0 in (14.02 m)
- Wingspan: 71 ft 11 in (21.92 m)
- Height: 14 ft 9+1⁄2 in (4.509 m)
- Wing area: 979.5 sq ft (91.00 m2)
- Empty weight: 6,370 lb (2,889 kg)
- Gross weight: 10,200 lb (4,627 kg)
- Powerplant: 2 × Bristol Jupiter VIIIF 9-cylinder air-cooled radial engines, 460 hp (340 kW) each
Performance
- Maximum speed: 139 mph (224 km/h, 121 kn) at 6,500 ft (2,000 m)
- Range: 520 mi (840 km, 450 nmi)
- Service ceiling: 20,800 ft (6,300 m)
- Time to altitude: 6 min 42 s to 6,500 ft (2,000 m)
Armament
- Guns: 2 × .303 in (7.7 mm) Lewis guns. One in nose, other in either dorsal and ventral gun positions
- Bombs: 1,040 lb (473 kg) total
See also
Related development
Related lists
References
Notes
- ^ a b c Taylor 1969, p. 325.
- ^ a b Jarrett Aeroplane Monthly November 1994, pp. 19–20.
- ^ Mason 1994, p. 180.
- ^ "Bobolink to Delta, Part III." Flight, 8 July 1955, p. 51.
- ^ Brew 1993
- ^ National Advisory Committee for Aeronautics, Aircraft Circulars No. 71 'The Boulton and Paul "Sidestrand I" Bomber Airplane (British)'
- ^ a b c d e AIR 27/801/1 Squadron Number: 101 Summary of Events: 1928 Mar 01 - 1940 May 31 – via National Archives
- ^ "Dearly Remembered", Flight, 23 October 1969, archived from the original on 20 November 2014
- ^ a b Taylor 1980, p. 344.
- ^ Mason 1994, p. 182.
Bibliography
- "The Boulton & Paul Sidestrand I", Flight, vol. XX, no. 1005, pp. 206–213, 29 March 1928, archived from the original on 3 October 2013 – via Flight Global Archive
- Brew, Alec. Boulton Paul Aircraft since 1915. London: Putnam, 1993. ISBN 0-85177-860-7.
- Jarrett, Philip. "By Day and By Night: Sidestrand and Overstrand, Part 1." Aeroplane Monthly, Vol. 22, No. 11, Issue 259, November 1994, pp. 18–23. London: IPC. ISSN 0143-7240. .
- Jarrett, Philip. "By Day and By Night: Sidestrand and Overstrand, Part 2." Aeroplane Monthly, Vol. 22, No. 12. Issue 260, December 1994, pp. 18–23. London: IPC. ISSN 0143-7240.
- Mason, Francis K. The British Bomber since 1912. London: Putnam, 1994. ISBN 0-85177-861-5.
- Taylor, John W.R. "Boulton and Paul Sidestrand". Combat Aircraft of the World from 1909 to the Present. New York: G.P. Putnam's Sons, 1969. ISBN 0-425-03633-2.
- Taylor, Michael J.H., ed. "Boulton Paul Sidestrand".Janes's Encyclopedia of Aviation, Vol. 2. Danbury, Connecticut: Grolier Educational Corporation, 1980. ISBN 0-7106-0710-5.
- Thetford, Owen. "By Day and By Night: Sidestrand and Overstrand, Part 3 Service History." Aeroplane Monthly, Vol. 23, No. 1, Issue 261, January 1995, pp. 32–39. ISSN 0143-7240.
- Winchester, Jim. Bombers of the 20th Century. London: Airlife Publishing Ltd., 2003. ISBN 1-84037-386-5.