CHAPTER FIVE

Fairey Fulmar

The Fulmar was unusual in that it was developed from a design for a two-seat, single-engine bomber, which was, in effect, a smaller, cleaned up version of the Battle. The Fairey P.4/34 bomber prototype, created by Marcelle Lobelle, was designed to meet a light day-bomber specification and was in direct competition with the Hawker Henley. However, following a change of policy at the Air Ministry, the requirement for a high-performance attack aircraft was dropped, which left the way clear for the type to be adapted to meet Specification O.8/38 for a two-seat fighter for the Fleet Air Arm. The first P.4/34 (K5099) had been taken into the air for the first time by Fairey test pilot Chris Staniland on 13 January 1937, with the second prototype (K7555) following on 19 April 1937. Both aircraft were powered by a Rolls-Royce Merlin II of 1030 hp and attained a top speed of 284 mph.

K7555 was assessed by A&AEE at Martlesham Heath between 24 September and 11 October 1937. The subsequent report, although generally satisfactory, highlighted several areas of concern. The aircraft’s stalling characteristics were marginal as a fore-and-aft pitching motion set in, together with some lateral instability. If back stick was maintained with the flaps and undercarriage up, there was also a tendency for the right wing to drop, and if elevator control had not been centralised it was thought that a spin might have developed. The rudder was also criticised for being too heavy at speeds above 80 mph IAS and it was found that the bias gear had to be used to maintain balanced flight. Other criticisms were that the elevator trimmer was too low-geared and that the ground attitude when compared with the stalling angle was too shallow, which caused difficulty on landing as it was possible for the tailwheel to contact the ground first as the aircraft was flared on touchdown. The aircraft was also considered to be excessively stable directionally. Together with the heavy rudder, this meant that flat turns were virtually impossible.

The Fulmar bore a strong resemblance to its clean-lined predecessor, but featured a longer radiator duct under the nose, a non-continuous canopy, folding wings, catapult points, dinghy stowage and eight 0.303 in Browning machine-guns mounted in the wings. Unlike contemporary land-based fighters, it was required to have a two-man crew, with an observer in the rear cockpit to assist with navigation as radio location aids were only just being developed. It was fitted with a 1080 hp Merlin VIII. As much testing had already been carried out on the P.4/34, it was decided that there was little point in ordering a prototype, and the first Fulmar to fly was actually the first production machine (N1854), which was taken into the air on 4 January 1940 by Duncan Menzies.

The forward fuselage comprised a tubular steel framework, with a monocoque rear section with Alclad metal sheet covering. The wing consisted of stub planes with outer wings, all covered in Alclad sheeting. The stub planes were attached to two spars, which passed through the fuselage, and the outer wing sections were built around two girder spars with T-section booms. The tailplane comprised two built-up spars and diaphragm-type ribs of sheet Duralumin, the fin being of similar construction. The elevators and rudder had tubular steel spars and Duralumin ribs. All the controls were fabric-covered, with the exception of the lower portion of the rudder, which formed the tail end of the fuselage and was covered with Alclad sheeting.

Handling trials were carried out at Boscombe Down in late 1940 using N1854, N1855 and N1858 and deck landing trials took place aboard HMS Illustrious. Access to the cockpit was assisted by two hand-grips and a non-slip walkway on the wing root, although even this became slippery when wet. The front seat was comfortable, but it was difficult to raise it from its lowest position if the pilot kept his feet on the rudder bar. The seat in the rear cockpit revolved when a spring catch was released, although there was barely enough room for the occupant’s knees due to equipment stowed in various locations. The noise level in the front cockpit was high, which resulted in partial deafness after prolonged flights. The observer fared a little better in this respect, but communication between the cockpits, which was by voice pipes, was not particularly effective. Both cockpits were found to be uncomfortably hot at low altitudes and there was no apparent variation in temperature with the heat control on or off. Unlike the Battle, the cockpit floor of the Fulmar ended at the rudder bar, so that there was an open space between the rudder and engine bulkhead, through which warm air was able to enter from over the radiators. A reduction of several degrees was effected by blocking off this space with plywood sheet, but there still appeared to be no difference when the heat was set to on. Ventilation also left something to be desired, as with the hood open, exhaust heat from the manifolds entered the front cockpit, instead of the cold air that was required. The observer could either open his hood or small sliding panels to admit fresh air.

The view from the front cockpit was generally good, except when taxying, but downwards it was obstructed by the wing. No clear vision panel was fitted. The general layout of the controls was similar to the Battle. A throttle box lay conveniently to hand on the port side of the cockpit, which comprised a throttle lever in the centre with the mixture control to the left and propeller control to the right. A friction damper was fitted, which stopped the lever moving from the position it had been set. The elevator and rudder trimmer controls were located under the throttle box. The former was easy to operate, but the rudder trim was just the opposite as it consisted of a small wheel let into the cockpit side, only half of which extended into the cockpit. This was rather annoying, as the aircraft was very sensitive to directional trim, which meant that the trimmer had to be used frequently. The elevator trim indicator had an unfortunate tendency to show different readings at different heights and also altered over time, considering that the trim tab was very powerful, this was considered to be quite a serious fault.

The flap control was located on the floor to the left of the pilot, the indicator being mounted on the left-hand side of the panel. It was easy to use and the flaps could be stopped in any position. Alongside was the undercarriage control, which could not be moved to the retracted position until a ‘stirrup’ safety lock had been disengaged. An indicator was mounted on the panel, showing a green light for each wheel when the undercarriage was down and a red light for each when the wheels were moving up or down. A horn sounded if the throttle was cut with the undercarriage still up, but this could be deactivated, if required, by a cut-out on the throttle box. The brakes were operated hydraulically by a hand lever on the control column.

The only means by which an emergency exit could be made was by sliding the hood open. The original hood for the front cockpit was found to be far too weak and flight with it in any intermediate position was considered inadvisable above 250 mph IAS. A revised hood was then fitted, but there was no way of locking it in anything other than the fully open position. This was felt to be unsatisfactory, as the hood could not be kept closed on the ground owing to the aircraft’s attitude. Should the aircraft come to rest on the ground inverted, it was extremely unlikely that the front and rear canopies could be opened and no break-out panels were fitted.

The Fulmar was flown at several loadings ranging from 8500 lb (forward CG limit) to 9800 lb (extended aft CG). The maximum overload weight was 10,624 lb. Owing to the wide-track undercarriage, ground handling was straightforward and the aircraft showed no inclination to lift its tail even at forward CG. Taxying in crosswinds of up to 25 mph could be carried out easily. For the shortest take-off run it was normal to set 15 degrees of flap, but at most normal airfields the Fulmar could take off without flap. It tended to swing to the left but this could easily be held by right rudder. After the tail came up a particular characteristic of the aircraft became apparent, as it was prone to ‘crabbing’ bodily to the left, although the aircraft was usually airborne before this could cause any major embarrassment. The take-off speed was around 63 mph IAS.

Once airborne, it was recommended that the speed be increased to 100 mph IAS before raising the flaps. By this time 200 ft had been gained, which provided a sufficient safety margin as there was appreciable sink when the flaps were raised, together with a nose-up change of trim. The undercarriage came up in about ten seconds and could be raised as soon as the aircraft was clear of the ground, as there was little trim change, but an immediate effect on forward speed. The best climb speed was 115 mph IAS up to 7000 ft thereafter decreasing by 1 mph per 1000 ft. However, the recommended speed was 125 mph IAS up to 7000 ft as the aircraft was much more comfortable to fly at this speed and the time to 20,000 ft was only one minute longer.

In level flight the elevators and ailerons were light, quick in response and effective. The rudder was light for small movements, but tended to become heavy with large movements, although it was fairly quick in operation and effective. As was to be expected, all the controls became heavier with increase of speed. One particular quirk that was noted was a ‘flat spot’ in the elevator control when the control column was central. The amount of trim available was just enough to cover both limits of CG.

Stability checks confirmed that the Fulmar was laterally and directionally stable at all speeds, but longitudinally it exhibited some characteristics that were very similar to the Blackburn Skua. Although it was stable with the engine on, in the climb the aircraft was unstable at 125–130 mph IAS, but not to such an extent as to make accurate speed-keeping difficult. If the speed was reduced below 115 mph IAS, however, the nose tended to come rapidly up to the stall unless firmly checked by pushing the control column forward. In the glide with the engine off, the aircraft was unstable with the flaps and undercarriage up and was even more unstable in the landing configuration. In level flight the aircraft was stable but not markedly so, even at full throttle.

The stalling speeds with the flaps and undercarriage up and down were 72 mph IAS and 61 mph IAS respectively (4 mph higher with unsealed gun ports). Very little force was required to bring about the stall, which occurred with the control column only slightly back from the central position. The only warning was a slight fore-and-aft pitching and a loss of elevator effectiveness, the stall being announced by the starboard wing dropping with a pronounced snatch of the ailerons. The wing could not be raised by the aileron and if the control column was moved further back the aircraft dropped sharply to the left, almost in a half roll, but did not spin. The stalling characteristics with the flaps and undercarriage down were very similar. Slow speed turns could be made in either direction down to 76/66 mph IAS depending on configuration, the elevator having to be used with care because of a tendency to tighten up.

The approach was normally carried out at 95 mph IAS. Lowering the flaps produced a nose-down trim change, but this could be trimmed out easily before reducing speed to 85 mph IAS prior to landing. Although the aircraft could be handled reasonably well with the engine off, it was advisable to leave a little engine on to improve the effectiveness of the rudder and elevator. In the case of a baulked landing, opening up to full power caused the aircraft to become tail heavy, although this did not cause any particular problems and it could be retrimmed before commencing the climb.

Only two landings were possible from HMS Illustrious, which was sailing with an over-deck wind speed of 30 kt. Compared with other deck-landing types the Fulmar did not appear to be as stable laterally, the ailerons having to be used continuously on the approach. This was made at 78 mph IAS, although it was thought that this figure could have been lowered with more practice. About one-third throttle was maintained right down to the deck and the landing itself was straightforward. On take-off, despite commencing the run on the centreline, the Fulmar’s tendency to crab to the left caused some initial concern, although it was easily airborne before there was any danger of going over the side.

Normal aerobatic manoeuvres could be carried out without difficulty. Loops were best commenced at a minimum speed of 240 mph IAS, but excessive accelerations over the top, caused by too much use of elevator, were to be avoided as the aircraft was liable to flick out in a half roll. When carrying out an intentional half roll off the top of a loop, the entry speed had to be increased to 280 mph IAS. Slow rolls could be made in either direction from an initial speed of 160 mph IAS. Coarse rudder was needed during the last quarter of the roll to prevent the nose from dropping. When inverted, the engine tended to cut out but this could be overcome by ‘falling out’ of the manoeuvre slightly, as in a barrel roll.

A number of spins were carried out, with entry being made from a gliding turn. If the aircraft was stalled in a gliding turn in either direction, the left wing would drop, followed by a spin with the nose well down and a high rate of rotation. After the first turn the aircraft was reluctant to continue its rotation, unless pro-spin controls were maintained, and as soon as the controls were set for recovery, the spin ceased. Although the recovery began immediately, due to the steep nose-down attitude a good deal of height was lost, and even an incipient spin would result in height loss of 2–3000 ft. Spins to the right were possible, but it was difficult to overcome the aircraft’s inclination to spin to the left.

Diving trials involved N1855 at a take-off weight of 9800 lb. A total of six dives were made with three different throttle positions (fully open, one-third open and closed) and dive angles of 30, 50, 60 and 90 degrees. The highest speed recorded was 415 mph IAS in a 90-degree dive from 16,000 ft. The aircraft was trimmed to fly level at full throttle before the dive was entered by half-rolling and pulling through into the vertical. It was extremely steady in the dive and only slight forward pressure was required to maintain the desired angle, together with slight pressure on the rudder. As the limit was approached (435 mph IAS) the ailerons and rudder became very heavy, but the elevator remained reasonably light throughout. An attempt was made to apply a 10-degree yaw in the dive, but this proved to be impossible because of the heaviness of the rudder control. Recovery from the dive was commenced at 5500 ft and was complete by the time that 4000 ft was reached, with a maximum acceleration in the pull-out of 4 g. During this series of dives, minor damage was caused to the starboard side and bottom engine cowlings. The cover for the rear ammunition box was also torn off.

The overall assessment of the Fulmar was that it was easy and pleasant to fly. However, because of its relatively low top speed and modest rate of climb and service ceiling, it could not be compared with land-based fighters of the day. Although it was fairly manoeuvrable at low to medium speeds, it was completely outclassed by the Hurricane due to the heaviness of its ailerons in a dive. The Fulmar’s forward-firing armament was adequate for its role, but since there was no rear-mounted gun, the top speed needed to be improved (as a wartime expedient some aircraft were fitted with a Vickers ‘K’ 0.303-in gas-operated machine-gun in the rear cockpit).

Climbing trials were carried out using N1858 powered by a Merlin VIII driving a Rotol variable-pitch propeller of 11 ft 6 in diameter. The best rate of climb was 1220 ft/min at a full throttle height of 7000 ft which was attained in six minutes. The greatest height reached was 21,600 ft and the absolute ceiling was estimated at 23,700 ft. The full results were as follows:

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Take-off and level-speed trials were also performed by N1858. The take-off run was 320 yards when converted to zero wind and ISA conditions, with 510 yards being needed to clear 50 ft. The top speed was 246.5 mph TAS at a full throttle height of 9000 ft. The full results were as follows:

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Further speed trials were undertaken by N1854, which was flown at a take-off weight of 10,620 lb using 100 octane fuel and with the engine boosted to +9 lb/sq.in instead of the more normal +4 lb/sq.in. Its low-level performance was improved and at 1000 ft a top speed of 250 mph TAS was recorded. The maximum speed was 255.5 mph TAS at a full throttle height of 2400 ft but above this height performance was gradually reduced so that parity with N1858 was reached at 10,000 ft.

The Fulmar I entered service with No. 808 Squadron at Worthy Down in June 1940 and a total of 250 were to be produced. Subsequent aircraft were designated Fulmar II and were powered by a Merlin XXX of 1300 hp. Other changes included a revised Rotol propeller, a tropicalised radiator and oil cooler, and a fully mass-balanced rudder. The prototype Fulmar II was N4021, a converted Mark I, which was flown for the first time on 20 January 1941.

During early testing of the Fulmar II, the rudder, which was not then fully mass-balanced, was suspected of being responsible for an aircraft breaking up in a dive. The mass-balance was therefore increased and diving trials were carried out at Boscombe Down using N4079 in order to assess its suitability. The range of the elevator and rudder trimmers was also checked, since early flights had suggested that these might not be adequate. The aircraft was dived to 415 mph IAS at both forward and extended aft CG (although the maximum permissible diving speed was 435 mph IAS, it was thought that this speed would not be achieved in service due to excessive height loss). In the dive, rudder was applied in both directions. The aircraft behaved normally with no vibration or control surface instability and it was also found to have sufficient elevator and rudder trim for all conditions of flight. As a result of the trial, the fully mass-balanced rudder was cleared for use on production aircraft.

Fuel consumption trials were carried out with N4021, which showed a maximum still air range of approximately 950 miles from a total fuel capacity of 155 gallons. This was obtained with a weak mixture at 5000 ft using 1600 rpm and 2 lb/sq.in boost. The speed was 142 mph IAS, which was a little lower than the best speed for comfortable control. This was achieved at 150 mph IAS with 1650 rpm and 1.2 lb/sq.in, but the range was slightly reduced at 925 miles. The maximum endurance was 6.18 hours. Further consumption trials were made with X8641, fitted with a jettisonable 60-gallon overload fuel tank under the fuselage near the wing trailing edge. The maximum still air range was found to be 1100 miles at 5000 ft and 140 mph IAS (1750 rpm, 0 lb/sq.in boost) with an endurance of 7 hours.

Further Fulmar trials involved N1859 for radiator suitability, cockpit heating and CO contamination tests, X8756 for Identification Friend or Foe (IFF) tests and N4079 for flame damping investigations with triple ejector fishtail exhausts (with and without anti-glow paint). X8757 was also used for brief handling tests with a small bomb container fitted under the fuselage loaded with three 65-lb bombs. A bomb release was made at 243 mph IAS at a height of 50 ft in a shallow dive without any alteration to basic handling.

Two Fulmar IIs (N4016 and N4079) were also used for Rocket Assisted Take-Off Gear (RATOG) trials at RAE Farnborough from May to July 1941 and again in July 1942. It was hoped that the aircraft could be airborne within 300 ft at a take-off weight of 9800 lb. The rocket used was a standard 3 in type. The rocket carrier was fitted to the standard catapult spools and was designed to take up to six rockets on each side, which were arranged to fire slightly downwards with respect to the aircraft’s axis. A plate was fitted between the aircraft and the rockets to minimise the effects of a possible burst rocket. After take-off, the carrier could be jettisoned by a device incorporated in the rear spool, the carrier then rotating through 30 degrees about the front spools before falling away. Modifications to the aircraft were few, comprising the various electrical connections, together with a firing control unit and switchbox.

The take-off was begun in the normal way and when a speed of about 20 knots had been reached, the pilot pressed the firing button mounted on top of the throttle lever. The rockets then fired at pre-determined intervals so long as the firing button was kept depressed. During tests with N4079 at a take-off weight of 10,580 lb, take-off runs were achieved well within the limit set and with a 5-knot headwind the aircraft was airborne in only 55 ft. Acceleration levels were in the order of 2 g. The behaviour of the aircraft on a rocket assisted take-off was normal in every way and it was considered that a pilot of average experience would have little difficulty. The trials also showed that rocket blast on aircraft parked directly behind was negligible and RATOG was also feasible on the wooden decks of auxiliary carriers, assuming that the decks had been hosed down beforehand.

The Fulmar provided a much-needed boost to the FAA’s capability in the early years of the Second World War. It was not superseded until 1943, when it was replaced by the Seafire. It was first in action against the Regia Aeronautica in the Mediterranean during the protection of convoys heading for Malta, destroying ten Italian bombers between September and October 1940. Fulmars were also involved in providing cover for the Taranto operation in November 1940, during which they shot down six defending fighters, and fought in the defence of Crete in March 1941. By this time, Fulmars were serving far and wide, providing cover for Russian convoys as well as air defence over Ceylon, which was threatened with invasion by the Japanese. In addition to continued duty in Malta, Fulmars were also active in North Africa defending the Suez Canal zone and later were involved in Operation Torch, the Allied invasion of Algeria and Morocco in November 1942. The Fulmar remained in first-line service in small numbers until the end of the war, its heavy armament and excellent endurance being put to good use as a night-fighter protecting Arctic convoys.

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