Sage Type 4

Sage Type 4
Role	Floatplane
National origin	United Kingdom
Manufacturer	Frederick Sage & Company
First flight	3 July 1917
Number built	2
Developed from	Sage Type 3

The Sage Type 4 was a prototype British floatplane of the First World War. It was a designed as a two-seat reconnaissance aircraft for the Royal Naval Air Service, but was chosen for service as a floatplane trainer, although the end of the war resulted in production being cancelled.

Design and development

In early 1917, the Peterborough based woodworking company of Frederick Sage & Company designed a two-seat patrol floatplane for the Royal Naval Air Service based on Sage's Type 3 landplane trainer. Like the Type 3, the new design, the Sage Type 4, was a single-engined biplane. Pilot and observer sat in separate tandem cockpits, with the pilot occupying the front cockpit, while the wireless operator/observer sat in the rear cockpit, with both crew members having good visibility. The aircraft was powered by a single 150 hp (112 kW) Hispano-Suiza 8 water-cooled V-8 engine in the nose driving a tractor propeller. Undercarriage consisted of two main floats under the wing the a further tail float.^[1]^[2]^[3]

The prototype Sage Type 4a (serial number N.116^[4]) first flew on 3 July 1917.^[5] The type demonstrated excellent handing during testing, being capable both of flying aerobatic manoeuvres while still being stable enough to be easily flown "hands-off".^[6] Despite this, the type was rejected for service as a patrol aircraft, but it was recommended that it instead be adapted into a float-plane trainer. The aircraft was fitted with dual controls and the engine mounting was modified to allow any one of a variety of 200 hp (149 kW) engines to be fitted. N.116 was converted to the new standard, being fitted with a Sunbeam Arab and flew as the Sage Type 4b on 17 May 1918.^[5]

Sage also designed a revised version, the Sage Type 4c with folding wings of increased wingspan (39 ft 7+1⁄4 in (12.07 m) compared with 34 ft 6 in (10.52 m) for the earlier aircraft and powered by a 200 hp Hispano Suiza engine, with a prototype flying on 12 October 1918.^[7]

Both the Type 4b and 4c were adopted as standard training floatplanes for the RNAS, but the end of the First World War resulted in production plans being abandoned.^[7]^{[nb 1]}

Variants

Type 4a: Two-seat patrol seaplane, powered by 150 hp (110 kW) Hispano-Suiza 8A engine. One prototype built. Converted to Type 4b.^[1]
Type 4b: Two seat floatplane trainer, powered by 200 hp (150 kW) Sunbeam Arab engine. Converted from Type 4a.^[5]
Type 4c: Revised floatplane trainer with folding wings. Powered by 200 hp (150 kW) Hispano-Suiza 8B engine. One example built.^[7]

Specifications (Sage 4c)

Data from British Aeroplanes 1914–18^[9]

General characteristics

Crew: 2
Length: 37 ft 6 in (11.43 m)
Wingspan: 39 ft 7.25 in (12.0714 m)
Height: 11 ft 7 in (3.53 m)
Wing area: 386 sq ft (35.9 m²)
Empty weight: 2,215 lb (1,005 kg)
Gross weight: 2,875 lb (1,304 kg)
Fuel capacity: 35+1⁄2 imp gal (42.6 US gal; 161 L)
Powerplant: 1 × Hispano-Suiza 8B water cooled V8 engine, 200 hp (150 kW)
Propellers: single blade two bladed propeller, 9 ft (2.7 m) diameter

Performance

Maximum speed: 97.2 mph (156.4 km/h, 84.5 kn) at 3,000 ft (910 m)
Stall speed: 45 mph (72 km/h, 39 kn) (landing speed)^[6]
Endurance: 2 h 30 min
Service ceiling: 13,700 ft (4,200 m)
Time to altitude:
- 8 min to 5,000 ft (1,520 m)
- 21 min 20 s to 10,000 ft (3,050 m)

Notes

^ Some sources indicate that an order for 29 Sage Type 4s was cancelled in October 1918 to pay for Norman Thompson N.T.2B flying boat trainers.^[8]

References

^ ^a ^b Bruce 1957, p. 464.
^ Uppendaun 2004, p. 69.
^ Flight 24 July 1919, pp. 974–975.
^ Bruce 1957, p. 468.
^ ^a ^b ^c Bruce 1957, p. 465.
^ ^a ^b Flight 24 July 1919, p. 975.
^ ^a ^b ^c Bruce 1957, p. 466.
^ Goodall 1995, p. 19.
^ Bruce 1957, pp. 466–469.

Bibliography

Bruce, J.M. British Aeroplanes 1914-18. London:Putnam, 1957.
Goodall, Michael H. The Norman Thompson File. Tunbridge Wells, Kent, UK: Air Britain (Historians) Ltd, 1995. ISBN 0-85130-233-5.
""Milestones" The Sage Machines". Flight, 24 July 1919. pp. 971–975.
Uppendaun, Bob. "Sage-Like Thoughts:The Products of Frederick Sage & Co". Air Enthusiast, No.110, March/April 2004. pp. 68–69.

[9] Some sources indicate that an order for 29 Sage Type 4s was cancelled in October 1918 to pay for Norman Thompson N.T.2B flying boat trainers.^[8]

[Bruce_p464-1] Bruce 1957, p. 464.

[AE_p69-2] Uppendaun 2004, p. 69.

[Flight_p974-5-3] Flight 24 July 1919, pp. 974–975.

[Bruce_p468-4] Bruce 1957, p. 468.

[Bruce_p465-5] Bruce 1957, p. 465.

[Flight_p975-6] Flight 24 July 1919, p. 975.

[Bruce_p466-7] Bruce 1957, p. 466.

[File_p60-8] Goodall 1995, p. 19.

[Bruce_p466-9-10] Bruce 1957, pp. 466–469.

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