A short-lived Squirt

By 1943, the World War II “island hopping” campaign in the Pacific made many in the military appreciate the usefulness and operational flexibility of the water-based fighter.

The Japanese float plane version of the Zero fighter, operating from small, protected lagoons, had given the Japanese a unique defensive weapon in areas with no airfields, so Allied aircraft designers began to look at the concept.

The British especially thought that a seaplane fighter might be very useful, since their mission toward the end of the war included forcing the Japanese out of Thailand and Vietnam. The British aircraft carriers were involved with the U.S. Navy in the final assault on Japan, so the challenge was how to provide air cover for the British forces in Southeast Asia.

The large number of coastal inlets and lagoons were ready bases if a seaplane fighter was available. But seaplane fighters had a major performance handicap – the need for large floats to keep their propellers out of the water. The drag of such floats meant a seaplane fighter could not compete in level speed with its land-based counterpart.

Flying boat hulls, on the other hand, could be aerodynamically streamlined but again had to be tall – and drag inducing – to keep the propellers out of the water.
As turbojet engines became available at the end of 1943, the Saunders Roe Ltd. aircraft designers saw an opportunity to use the new engine to overcome this drawback. Since a jet engine did not require the clearance for a propeller, the aircraft could use a shallow, low-drag flying boat hull rather than drag inducing floats.

The jet’s notoriously long takeoff run would not be a problem with a water runway, so the theory was that the jet seaplane fighters’ range and all around performance might well equal or exceed land- or carrier-based jet aircraft.

In early 1944, Saunders Roe approached the Air Ministry with a seaplane fighter design and was rewarded with a development contract for three prototypes in May 1944.

The aircraft, the SR.A/1, was of light alloy construction throughout and had a fairly conventional appearance with a high mounted straight wing, a high mounted horizontal tail to clear off the water and a single, high mounted nose air intake.
Soon (and informally) named the “Squirt,” the SR A/1 was powered by two slender axel flow Metropolitan-Vickers Beryl F2/4 turbojets chosen because two of them could be mounted side-by-side in a relatively narrow fuselage. The engine developed about 3,250 pounds of thrust and the exhaust pipes were on either side of the fuselage just behind the trailing edge of the wing.

The Squirt had stabilizer floats on the outer wing that retracted into streamlined pods after takeoff and carried the standard British fighter armament of four 20 millimeter cannons grouped in the forward hull above the air intake.

The first of the three prototypes – the world’s first jet flying-boat – made its initial flight on July 16, 1947, and was followed the two others equipped with steadily more powerful Beryl engines.

Performance and handing were considered excellent. The SE A/1 had a top speed of more than 500 knots, a maximum climb rate of 5,800 feet per minute and an endurance of 2.4 hours, all comparable to contemporary straight wing jet fighters. There were some problems, mainly with the visibility from the heavily framed canopy. It was mounted high on the middle of the fuselage and the pilot’s view was limited and disappeared during the take-off run, and even in flight offered limited visibility – a true handicap in a fighter.

But there were more fundamental problems by the time the flight tests were underway. Metropolitan-Vickers, the producer of the Beryl engine, had withdrawn from jet engine development and only a limited number of Beryls were available. But the real blow to the SR A/1 was the success of the smaller carriers in the Pacific, which eliminated the need for seaplane fighters.

The project was suspended and the prototype Squirt put into storage in 1950. It was briefly resurrected in November 1950 with the outbreak of the Korean War, but by then it was obsolete and the lack of engines forced a final cancellation of the program. The prototype last flew in June 1951.

One of the Squirt’s admirers was the world’s greatest test pilot, Royal Navy Capt. Eric “Winkle” Brown, Commander of the British Empire. As one of the test pilots in the program, Brown apparently took delight in returning to his coastal base by flying the Squirt upside down at very low level over the Royal Yacht Squadron boats at nearby Cowles Castle.

Unfortunately for Brown, while he was taxiing the SR A/1 back to its mooring after one of these missions, he hit an underwater object and punctured the hull. The aircraft quickly sank and Brown had to be unceremoniously fished out of the bay. The last SR A/1 was mothballed for good in the summer of 1951, but one example is on exhibit at the Southampton Hall of Aviation in the UK.
(Dr. Michel is currently deployed downrange)