Winkle’s winner

Regular readers of this column will have noted frequent references to the reports of British test pilot Capt. Eric “Winkle” Brown, Royal Navy, who flew more types of aircraft than anyone else in history (487, counting only main types, not different models of the same aircraft) and holds the world record for number of aircraft carrier landings (2,407). Brown was also a prolific writer, and this leads one to the question, “which were his favorite aircraft?”

Brown was never one to shy away from being judgmental, but his list of favorites include the usual suspects — the Supermarine Spitfire, Avro Lancaster (with boosted controls), North American F-86 Sabre, McDonnell F-4 Phantom II — as well as two lesser known types: an early jet, the Hawker P. 1040, prototype of the widely built Hawker Sea Hawk, and the aircraft Brown said was “unexcelled in getting everything together in near perfection,” the De Havilland Hornet twin piston engine fighter.

The development of the little known Hornet began in 1942 as a fighter version of the de Havilland Mosquito and was intended to cure the RAF Fighter Command’s major deficiency — the lack of a long range fighter.

Developing a twin engine fighter that would be agile enough for air-to-air combat was a tricky business. The first thing De Havilland did was turn to the Rolls Royce engine company to see if they could produce a slim profile version of its Merlin engine.

To provide minimum frontal area and low drag, Rolls Royce moved the engine accessories for a 2,030 horsepower engine to the rear of the nacelle, which made the nacelle long but slender, and fitted the engine with a four-blade variable-pitch propeller. With the engines, de Havilland offered a design to the Air Ministry and received an order for two prototypes in June 1943.

Developed from the aesthetically pleasing Mosquito, the Hornet was even more visually appealing. The fuselage had a bubble canopy mounted well forward, which provided excellent visibility, and its fuselage was much more slender than the fuselage of the Mosquito, which had side by side seating. The one-piece wing had a wood and metal internal structure with an undersurface of reinforced Alcad, a corrosion resistant sheet of aluminum surface layers metallurgically bonded to a high strength aluminum alloy core material.

The wings had a slender, laminar flow profile similar to the P-51 Mustang and Hawker Tempest. Clipped wings and large ailerons that extended close to the tips provided excellent roll control, especially at low speeds.

The long, thin Merlins were mounted low over the wing to provide the pilot with better visibility. Unusually for a British design, the Hornet’s propellers were counter rotating to cancel out torque, reduce adverse yaw and generally provide more stable and predictable behavior in flight.

At first the propellers rotated inward toward the fuselage, but this reduced the effectiveness of the rudder so the propellers were reversed to rotate outward.
The Hornet was armed with four short-barreled 20 millimeter Hispano V cannon firing through short blast tubes under the nose and had provision for limited underwing stores, usually two external fuel tanks or eight 60 pound rockets projectiles. 

The first prototype made its initial flight on July 28, 1944, and its performance exceeded the most sanguine predictions, with a top speed of 485 mph and an amazing climb rate of 4,500 feet per minute. The first Hornets did, however, show some longitudinal instability, so a filet was fitted to the vertical stabilizer and that solved the problem.

A production order followed and the initial batch of F. Mk. 1 Hornets were delivered on Feb. 28, 1945. Production aircraft were heavier and slower than the prototypes, but not by much, with a top speed of 472 mph. The newly equipped Hornet squadrons were scheduled to be part of the RAF’s Tiger Force for operations against Japan, but the war ended before they could be deployed.

One-hundred-thirty-two F. Mk. 3s, a later model with greater fuel capacity and a modified tail, were built. In 1951, many were sent to Malaya for use by the Far East Air Force against communist guerillas. They were the last piston engined RAF fighters to see combat.

From the beginning, de Havilland had been considering a carrier-based version of the Hornet for the Fleet Air Arm, so ease of control, especially at low speeds, and good pilot visibility had been built into the aircraft.  The navalized version, the Sea Hornet, became the first twin-engine, carrier-based fighter for the Royal Navy.
The lower rear fuselage was reinforced to take the carrier landing stresses and it was fitted with high-drag flaps, arresting gear, catapult hookups, stronger landing gear and upward folding wings. Surprisingly, the empty weight was almost the same, despite modifications, and after tests the Navy issued a production order for the Sea Hornet F.20.

The F.20 reached formal Royal Navy service in June 1947 and remained in service until 1955. But the most common Sea Hornet was the two-seat night fighter version, the NF.21. It carried with radar in the nose, flame dampers and a small bubble canopy on the rear fuselage for a radar operator and served well into the 1950s.

(For questions or comments, contact Dr. Michel at marshall.michel@ramstein.af.mil.)