P.Hare Royal Aircraft Factory (Putnam)
The Royal Aircraft Factory's only flying-boat design, the Coastal Experimental No 1 was first conceived in February 1917, to assist in combatting the growing threat to shipping posed by enemy submarines. W S Farren had overall responsibility for the design.
The C.E.1 was a two-seat pusher with a wooden hull which had a single step. The underside of the after portion was concave. Its empennage was carried on booms which met at the tailplane spar in a manner reminiscent of the F.E.8, and the fin and horn-balanced rudder were symmetrical above and below the tailplane. The wings were arranged to fold, the hinges being immediately outboard of the point at which the tailbooms joined the rear spar, a small section of the trailing edge having to be hinged upwards to make folding possible. Provision was made for up to three Lewis guns carried on pillar mountings, and for bombs carried beneath the lower wing.
Two prototypes were built, the first, N97, being powered by a 230hp R.A.F.3a and the second, N98, by a 260hp Sunbeam Maori, each engine driving a four-bladed propeller. After construction at Farnborough they were taken, in turn, to Hamble for assembly and testing, where N97 made its first flight on 17 January 1918, with its designer at the controls. Lateral control clearly gave some cause for concern because, following these trials, the ailerons were shortened and their horn balances removed.
Although the type completed service trials at the Isle of Grain, no production orders were placed because the Felixstowe F.2 was considered superior. The two prototypes were then used extensively in experiments to verify data obtained from tests on model hulls conducted in the tank at the National Physical Laboratory, particularly with regard to 'porpoising' when in motion on the water. Their eventual fate is unknown.
230hp R.A.F.3a (N97)
260hp Sunbeam Maori (N98)
span 46ft 0in
chord 7ft 0in;
gap 7ft 0in;
wing area 609 sq ft;
dihedral 3 1/2°;
length 36ft 3in;
height 13ft 4in.
N97 3,241lb (empty) 4,910lb (loaded)
N98 3,342lb (empty) 5,000lb (loaded)
max speed 88mph at sea level;
endurance 4 1/2hrs.
max speed 92mph at sea level;
endurance 3 3/4hrs.
G.Duval British Flying-Boats and Amphibians 1909-1952 (Putnam)
Royal Aircraft Factory C.E.1 (1917)
With the introduction of unrestricted submarine warfare by the German navy in February 1917, the urgent requirement for suitable aircraft capable of long oversea patrols became acute. The big F.2A flying-boats had not yet appeared, and the limited numbers of Curtiss H.12s and H.4s were heavily engaged. In an attempt to ease the situation, the Royal Aircraft Factory, despite their limited experience of marine aircraft, set up a design team under Mr. W. S. Farren (now Sir William Farren, c.b., m.b.e., f.r.s.) to build a two- seater single-engined flying-boat, designated Coastal Experimental 1. Work commenced in June 1917, and such was the speed at which it proceeded that the first prototype was despatched to Hamble for trials six months later.
To cut design problems to a minimum, several features of proven Factory machines were utilised, and the flight structure with the tail surfaces supported on booms had obvious F.E.2B association, in fact, the wing spans were almost identical. Such an arrangement permitted a short lightweight hull to be used, with no aerodynamic function save side-area, a reversion to the highly efficient Sopwith Bat Boat formula. The hull, boat-built and planked with mahogany, weighed only 527 pounds. The two cockpits were arranged in tandem, the pilot occupying the rear seat, and extensive glazing surrounded both cockpits, with sliding side panels for entry and exit. Side fins gave the planing bottom a reasonable width back to the single step amidships, and there was a water rudder at the stern. Three gun mountings of the pillar type were provided, one at the bow and two between the cockpits, with an external bomb-sight to starboard of the front cockpit. Bomb racks were attached to the underside of the lower wing centre section. The wings were arranged to fold backwards, outboard of the tail boom junctions, and a large-area single fin and rudder was fitted. The power unit of the first C.E.l, N97, was a 230 h.p. R.A.F. 3a pusher engine driving a four-bladed propeller. N97 made its first flight at Hamble on 17 January, 1918, piloted by Mr Farren, and after some control surface and radiator modifications, arrived at the Isle of Grain for official trials in March 1918. By this time, the U-boats were by no means having things their own way, and the testing of the C.E.l took on a more leisurely pace. Its performance was inferior to the F.2A, and slightly better than the Short 184 seaplane, but it could carry two 230-pound bombs and fly for four-and-a-half hours, which fulfilled its required task. No longer required on operations, N97 became a research aircraft, and was used for comparing the results of full-scale tests with those obtained on models in the Froude Tank at the National Physical Laboratory, with particular reference to the problems of porpoising, which had caused the failure of the first A.D. Boat in 1916. A second machine, N98, was completed in March 1918, the power unit in this case being the 260 h.p. Sunbeam Maori, and the performance reported to be slightly better than A797. N98 was stationed at Westgate in June 1919. It is reasonable to suppose that both C.E.1s were scrapped in the post-war economy reduction of the forces.
N97 - One R.A.F. 3a of 230 h.p.
N98 - One 260 h.p. Sunbeam Maori
Span: 46 feet
Length: 36 feet 3 inches
N97 - 4,912 pounds
N98 - 4,994 pounds
Total Area: 609 square feet
N97 - 88-5 m.p.h.
N98 - 92-5 m.p.h.
N97 - 4-5 hours
N98 - 3-75 hours
Armament: One Lewis gun, two 230-pound bombs
J.Bruce British Aeroplanes 1914-1918 (Putnam)
ALTHOUGH the Royal Aircraft Factory experimented with a floatplane version of the original F.E.2 and the H.R.E.2 floatplane, it produced only one flying boat. It was designated C.E.1, or Coastal Experimental, and was a two-seat flying boat intended for coastal patrol duties.
The C.E.1 was designed by W. S. Farren (later Sir William Farren, C.B., M.B.E., F.R.S.), and was of similar layout to the much earlier Sopwith Bat Boats. The engine drove a pusher airscrew, and the tail-unit was carried on tail-booms. The hull was a planked wooden structure and had a single step; the after portion of the hull had a concave underside. The fin and rudder were symmetrical above and below the tailplane, and the rudder had a horn balance at each end.
The mainplanes could be folded backwards, reducing the width of the aircraft to 20 feet 7 inches. The structure of the wings at the point of fold was unusual. The wings of the C.E.1 were hinged on the rear spars at the points where the tail-booms met the wings; from that point on each wing the break-line ran obliquely forwards and inwards to the front centre-section struts. To facilitate folding, a short portion of the trailing edge of each mainplane immediately outboard of the tail-booms was hinged and had to be lowered before the wings were folded.
Work on the design began early in June, 1917, and two prototypes were laid down. So well did the work of construction proceed that the first, N.97, was completed and sent to Hamble on Christmas Day, 1917. The first C.E.1 was assembled there and was flown for the first time by Mr Farren on January 17th, 1918.
This machine was powered by the 230 h.p. R.A.F. 3a engine, which at first had shutters only on the upper half of its radiator. In its original form, N.97 had horn-balanced elevators, and the ailerons extended inboard almost as far as the second pair of interplane struts. Subsequent tests necessitated some modifications, and by the time the C.E.1 reached the Isle of Grain Experimental Station for Service trials, plain elevators were fitted and the ailerons had been shortened. The engine installation was also modified, and the radiator had shutters over its entire length.
In April, 1918, the C.E.1 was used in a series of experiments which were conducted to check the agreement of full-scale results with those obtained by the use of a model hull in the William Froude National Tank at the National Physical Laboratory. During these tests the machine was flown by Lieutenant Hackforth, and later trials were made by Captain Goodwin.
The second C.E.1, N.98, appeared in 1918. It differed from N.97 chiefly in having the 260 h.p. Sunbeam Maori engine in place of the R.A.F. 3a.
Manufacturers: The Royal Aircraft Factory, Farnborough, Hants.
Power: 230 h.p. R.A.F. 3a; 260 h.p. Sunbeam Maori.
Dimensions: Span: 46 ft. Length: 36 ft 3 in. Height: 13 ft 4 in. Chord: 7 ft. Gap: 7 ft. Dihedral: 3 30'. Areas: Wings: 609 sq ft.
Weights (lb) and Performance:
Engine R.A.F. 3a Maori
No. of Trial Report N.M.132 N.M.20I
Date of Trial Report March 16th, 1918 July 30th, 1918
Type of airscrew used on trial T.28144 T.28188
Weight empty 3,241 3,342
Military load 710 581
Crew 360 360
Fuel and oil 601 711
Weight loaded 4,912 4,994
Maximum speed (m.p.h.) at
2,000 ft 88-5 92-5
5,000 ft 86 90
6,500 ft 85-5 87
m. s. m. s.
2,000 ft 5 30 5 30
5,000 ft 18 10 17 10
6,500 ft 29 00 26 35
service 6,800 7,500
absolute 9,000 10,000
Endurance (hours) 4 1/2 3 3/4
Armament: Three partly movable mountings, each capable of carrying a Lewis machine-gun, were provided. One was fitted in front of the forward cockpit and two between the cockpits, one on either side. Bombs could be carried under the lower wings.
Serial Numbers: N.97, N.98.
H.King Armament of British Aircraft (Putnam)
C.E.1. Two 230-lb anti-submarine bombs could be carried by this single-engined pusher flying-boat. There were three pillar-type mountings for Lewis guns, one in the front cockpit and two between the cockpits, one on each side of the hull.