Summary
The Caudron R.11 (or R.XI in contemporary usage), was a French three-seat twin-engine long range escort fighter biplane developed and produced by Caudron during the First World War.[2]
| R.XI | |
|---|---|
| |
| Role | Heavy fighter |
| Manufacturer | Caudron |
| Designer | Paul Deville[1] |
| First flight | 1916[2] |
| Introduction | 1918[2] |
| Retired | July 1922 |
| Primary user | France |
| Produced | 1917-1918 |
| Number built | 370 |
| Developed from | Caudron R.4 |
Development edit
The R.XI was intended to fulfill a French Corps d'Armee requirement for a long range three-seat escort fighter. Its design was similar to the Caudron R.4, but without a nose-wheel, and with longer wings and fuselage, with two bracing bays outboard the engines rather than three, along with a much larger tail. Hispano-Suiza 8Ba liquid-cooled V-8 engines were housed in streamlined nacelles just above the lower wing, fitted with frontal radiators, which replaced the air-cooled Renault engines used in the R.4.
Operational history edit
Production of the 1000 R.XIs ordered by the French Army began in 1917, with the first aircraft completed late in that year.[1]
The first escadrille, R 46, was equipped with the type in February 1918 and the last escadrille to form was R 246,[3] before the Armistice resulted in an abrupt end to production, at which point approximately 370 aircraft had been completed by Caudron, Régy Frères and Gremont.[1]
Variants edit
- Caudron R.XI C.3
- Heavy escort fighter with 160 kW (215 hp) Hispano-Suiza 8Bda engines.
- Caudron R.XII C.3
- R.XI with the more powerful 220 kW (300 hp) Hispano-Suiza 8Fb engines that were expected to boost performance. Sources differ, but it may have had a slightly increased wing area, to 60 m2 (650 sq ft) and an extra wing bay was added outboard of the engines. It first flew in November 1918 but was still undergoing testing in mid-1919 and no production followed despite plans to equip 12 escadrilles.[4]
- Caudron R.XIV Ca.3
- Similar to the R.XII, but armed with a 37 mm (1.5 in) Hotchkiss cannon in addition to the normal complement of 5 machine guns, and with further increased wing area, to 63 m2 (680 sq ft), and a larger, unbalanced rudder. A single example was built following the conversion of an R.XI to carry the cannon in August 1918.[4]
Operators edit
- Royal Air Force received two examples for evaluation as a bomber.[3]
- American Expeditionary Force received two examples for evaluation, and two others were detached to US units.[3]
Specifications (Caudron R.XI C.3) edit
Data from Davilla, 1997, p.168
General characteristics
- Crew: 3
- Length: 11.22 m (36 ft 10 in)
- Upper wingspan: 17.92 m (58 ft 10 in)
- Lower wingspan: 16.97 m (55 ft 8 in)
- Height: 2.8 m (9 ft 2 in)
- Wing area: 54.25 m2 (583.9 sq ft)
- Empty weight: 1,422 kg (3,135 lb)
- Gross weight: 2,165 kg (4,773 lb)
- Fuel capacity: 220 L (48 imp gal; 58 US gal)[5][6]
- Powerplant: 2 × Hispano-Suiza 8Bda V-8 water-cooled piston engines, 160 kW (215 hp) each
- Propellers: 2-bladed wooden fixed pitch propellers
Performance
- Maximum speed: 190 km/h (120 mph, 100 kn) at sea level[5]
- 183 km/h (114 mph) at 2,000 m (6,600 ft)
- 178 km/h (111 mph) at 3,000 m (9,800 ft)
- 173 km/h (107 mph) at 4,000 m (13,000 ft)
- 164 km/h (102 mph) at 5,000 m (16,000 ft)
- Range: 600 km (370 mi, 320 nmi)
- Endurance: 3 hours
- Service ceiling: 5,950 m (19,520 ft)
- Time to altitude:
- 2,000 m (6,600 ft) in 8 minutes 10 seconds
- 3,000 m (9,800 ft) in 14 minutes 30 seconds
- 4,000 m (13,000 ft) in 22 minutes 30 seconds
- 5,000 m (16,000 ft) in 39 minutes
- Wing loading: 39.9 kg/m2 (8.18 lb/sq ft) [7]
- Power/mass: 18.08 kW/kg (11.00 hp/lb)[7] This power to weight is wrong.
Armament
- Guns: 5 x 7.7 mm (0.303 in) Lewis machine guns
Related development
Aircraft of comparable role, configuration, and era
- SPAD SA.3
- Ponnier P.1
References edit
Notes edit
- ^ a b c Davilla, 1997, p.167
- ^ a b c Davilla, 1997, p.168
- ^ a b c d e f g h i Davilla, 1997, p.169
- ^ a b Davilla, 1997, p.170
- ^ a b Green and Swanborough 1994, p.111.
- ^ Grey, C.G. (1969). Jane's all the World's Aircraft 1919 (Facsimile ed.). London: David & Charles (Publishers) Limited. p. 224a. ISBN 0715346474.
- ^ a b French aeroplanes in service at the front, 1919, p.204
Bibliography edit
- Cony, Christophe (August 1997). "Aviateur d'Observation en 14/18 (3ème partie et fin)" [Aircraft observers in 1914-1918 (third and final part)]. Avions: Toute l'aéronautique et son histoire (in French). No. 53. pp. 16–21. ISSN 1243-8650.
- Davilla, J. J.; Soltan, A. (1997). French Aircraft of the First World War. Mountain View, CA: Flying Machines Press. ISBN 978-1891268090.
- "French aeroplanes in service at the front". Flight. 13 February 1919. p. 204.
- Green, W.; Swanborough, G (1994). The Complete Book of Fighters. New York: Smithmark. ISBN 0-8317-3939-8.
- Owers, Colin A. (2013). Caudron R.11. Windsock Datafile No. 161. Albatros Productions. ISBN 978-1906798338.