The Hawker Sea Hawk

v1.0.3 / 01 dec 01 / greg goebel / public domain

* The Hawker Sea Hawk, while not the first naval shipboard jet fighter, was an early example of its type that incorporated several ingenious engineering features and an extremely clean design. Although it did not have a significant history of combat operations, it provided excellent service as a first-line fighter for over a decade.

[1] ORIGINS

* While Hawker Aircraft was introducing their Fury prop-driven fighter in 1944, Hawker engineers began to consider how to apply the new jet engine technology to the Fury design. Rolls-Royce had just introduced a new turbojet engine, the B.41, to be named the "Nene", that had adequate thrust to propel the big Fury airframe. In November 1944, Hawker submitted a preliminary concept for a B.41-powered Fury to the British government, with the designation "P.1035".

The design team, working under Hawker's Sydney Camm, removed the piston engine from the nose of the Fury, moved the bubble canopy as far forward as possible, and put the B.41 engine in the middle of the aircraft. The intakes were positioned alongside the fuselage and the tailpipe went straight out the back.

After a little more thought, the Hawker engineers came up with a follow-on proposal in December 1944. The new design, designated the "P.1040", had a significant change in that the straight tailpipe was replaced with a split tailpipe, with an outlet in each wing root. This scheme meant the wing root had to be thickened, and so the intakes were placed in the wing roots as well. This new layout reduced the length of the of ducting and allowed fuel to be stored both fore and aft of the engine, preserving the aircraft's center of gravity as fuel was consumed. It also reduced the thrust losses suffered by aircraft with longer exhaust pipes.

The Fury's distinctive elliptical wing was abandoned for one with straight edges to simplify manufacturing, and the horizontal tailplane was raised to allow it to clear the jet exhaust. The new design was the first Hawker aircraft to have tricycle landing gear. With all the changes, the P.1040 no longer looked very much like a Fury. Armament was specified as four Hispano Mark 5 20-millimeter cannon.

The P.1040 was intended for RAF use. Government interest, however, was mild. The war would clearly be over before long, and both the RAF and the Royal Navy had other jet fighter designs either flying or in the works. Nonetheless, in October 1945, months after the guns had gone silent, Camm ordered the construction of a P.1040 prototype.

By this time, RAF interest had gone completely to zero. RAF planners believed that their new 950 KPH (600 MPH) Meteors would be the hottest thing in the air for the forseeable future. Hawker Aircraft, faced with massive cancellations of orders for their piston fighters, hastily modified the P.1040 design for carrier operation, and submitted the proposal to the Royal Navy in January 1946.

Much to Hawker's relief, the Royal Navy was impressed with the design and ordered three prototypes and a test item. Hawker completed the prototype already in progress to provide the initial aircraft, and quickly constructed the others. Camm's engineers then proceeded to refine the P.1040's design as a carrier-based interceptor. They also considered what could be done with the design to get the RAF interested again, an effort that eventually led to the extremely successful Hawker Hunter.

The first prototype of the P.1040 flew on 2 September 1947. The project was announced to the public a month later, disguised for some forgotten reason as a purely company-financed effort. This pretense was dropped when the second prototype flew a year later, on 3 September 1948. The second prototype had folding wings, a stinger-type arresting hook, and was fully armed. The second prototype was used in carrier trials that indicated a need for a slightly wider wingspan and longer arresting hook.

The third prototype took to the air on 17 October 1949. This aircraft was essentially a fully-functional production prototype, with longer arresting hook, provisions for "Rocket Assisted Take-Off Gear (RATOG)", and attachment points for drop tanks. The powerplant was the Rolls-Royce Nene 101, providing 2,270 kilograms (5,000 pounds) of thrust.

Service trials proved successful. On 22 November 1949, the Royal Navy ordered 151 examples of the new aircraft, now formally known as the "Sea Hawk".

BACK_TO_TOP

[2] SEA HAWK IN SERVICE

* The initial batch of 35 Sea Hawk "Fighter Mark 1s (F.1)" was partly used for further service trials, one of which ended disastrously when the aircraft's folding wings unlocked on take-off; and to provide the first examples actually delivered to Royal Navy Fleet Air Arm (FAA) squadrons in March 1953.

When Winston Churchill became Prime Minister again in 1951, he initiated a "Super-Priority" scheme to speed the production of certain critical aircraft, including the Sea Hawk. The end result was that manufacturing was relocated to Armstrong Whitworth Aircraft (AWA), another member of the Hawker Siddeley group. AWA built 60 more Mark 1s.

Pilots had noticed a tendency for the ailerons to oscillate, and to fix this problem the Sea Hawk "F.2" was produced, providing power-actuated ailerons and a few other small improvements. 40 were built.

The next variant, the Sea Hawk Fighter-Bomber "Mark 3 (FB.3)", first flew in March 1954. It incorporated a strengthened wing that could be adapted to carry a variety of stores. Test configurations included two 225 kilogram (500 pound) bombs and dual drop tanks; 20 7.62 centimeter (3 inch) rockets, each with a 27 kilogram (60 pound) warhead; and other combinations of bombs, rockets, and mines.

116 Mark 3s were built, but the Royal Navy was so overloaded with their Korean War commitments that they were unable to qualify most of these aircraft for full use of stores. Despite this embarrassing situation, an improved strike variant, the Sea Hawk "Fighter Ground-Attack Mark 4 (FGA.4)" was first flown in August 1954, and 97 were built in all.

By 1954, however, other nations were beginning to field aircraft that could break the sound barrier in level flight, and the performance of the Sea Hawk was beginning to become a concern. The Rolls-Royce Nene was a centrifugal flow engine, and it had become obvious by that time that this was a technological dead end for high-performance aircraft. The axial flow engine was clearly the way of the future.

Some improvements were still possible. When the 2,460 kilogram (5,200 pound) thrust Nene 103 became available, about 50 FB.3s and some FGA.4s were re-engined with the Nene 103, becoming known as Sea Hawk "F.5s". The increase in thrust was too small to significantly increase the aircraft's top speed, but it did provide an additional margin of safety for flight-deck operations.

The new Nene 103 was also engineered into new-build Sea Hawks. These new machines being designated the "FGA.6", and 87 were built. The FGA.6 was the only variant of the Sea Hawk to see combat action, providing close air support for the Anglo-Israeli-French Suez operation in November 1957. This was the first time the Sea Hawk drew blood in anger. The aircraft flew from the carriers HMS ALBION, HMS BULWARK, and HMS EAGLE. The Sea Hawks acquitted themselves well, but two were lost due to Egyptian ground fire and several others were damaged.

   HAWKER SEA HAWK FGA.6:
   _____________________   _________________   _______________________
 
   spec                    metric              english
   _____________________   _________________   _______________________

   wingspan                11.89 meters        39 feet
   length                  12.09 meters        39 feet 8 inches
   height                  2.64 meters         8 feet 8 inches

   empty weight            4,208 kilograms     9,728 pounds
   max loaded weight       7,327 kilograms     16,153 pounds

   maximum speed           695 KPH             600 MPH / 520 KT
   service ceiling         13,565 meters       44,500 feet
   range (no drop tanks)   1,270 kilometers    790 MI / 685 NMI
   range (drop tanks)      770 kilometers      480 MI / 420 NMI
   _____________________   _________________   _______________________