How the British made a jet fighter and a flying boat

When we think of seaplanes, we usually think of large propeller planes. Multi-engine aircraft like the PBY-5A Catalina and BV 238 came to define the class. However, seaplanes also came in the form of fighter aircraft like the OS2U Kingfisher and the A6M2-N Rufe based on the A6M Zero. Additionally, seaplanes persisted in the jet age with the Navy’s P6M SeaMaster. Notably, the first water-based jet aircraft was an attempt to create a flying boat jet fighter.

Saunders-Roe was adamant about the superiority of water-based aircraft (public domain)

Although their achievements are not as widely publicized, seaplane fighters proved to be quite effective during World War II. The Imperial Japanese Navy used them extensively in the Pacific. Able to operate from small coastal bases, seaplane fighters were not dependent on airfields or aircraft carriers. With their operational flexibility came a performance trade-off in the form of their bulky floats, but the Japanese seaplane fighters still posed a deadly threat to Allied forces.

Seeking to advance seaplane fighter design, British manufacturer Saunders-Roe sought to build a more capable aircraft using jet technology. Without a propeller, the plane could sit lower in the water and use a hull-type fuselage. By omitting the floats, a jet-powered seaplane could be both faster and more maneuverable than a conventional propeller-driven land fighter. Saunders-Roe, an established seaplane builder, also touted the logistical flexibility of seaplanes that could operate from virtually any body of water. This advantage was magnified with the proposed jet-powered seaplane, as early jet-powered aircraft had extremely limited range due to their high fuel consumption.

How the British made a jet fighter and a flying boat
A cut of the SR.A/1 (Saunders-Roe)

Although the British Air Ministry had little interest in seaplane fighters during World War II, Saunders-Roe designed a concept designated the SR.44 and presented it in mid-1943. Ministry officials were skeptical of the concept’s ability to operate at high altitudes, and Sauders-Roe modified and refined the concept. In April 1944, the Air Ministry issued a specification in response to the modified design and awarded a development contract for three aircraft to Saunders-Roe the following month.

The jet seaplane, designated SR.A/1, was intended for use in the Pacific. Japanese resistance continued to hamper Allied progress, so the project was initially given top priority. However, with the end of the war in August 1945, Saunders-Roe refocused its efforts on civilian seaplane projects. As a result, the first SR.A/1 prototype completed its first years of flight on July 16, 1947. The initial flight went so well that just two weeks later, the fifth flight was completed in front of officials military. These flights revealed that the aircraft had good performance and handling.

However, during the test and evaluation phase, two of the three SR.A/1 prototypes suffered accidents. This caused an interruption in testing and resulted in modifications to the third aircraft. In an effort to improve safety, the SR.A/1 was fitted with the first production Martin-Baker ejection seat. The seaplane was also equipped with an automatic docking system that allowed the pilot to dock the aircraft without any outside help or even having to leave the cockpit.

Despite the improvements, the need for a seaplane jet fighter was simply not there. Aircraft carriers had proven their ability to project air power during war, and escort ships had demonstrated their ability to protect aircraft carriers. With the Air Ministry’s loss of interest, Saunders-Roe put the project on hold and the surviving SR.A/1 prototype was put into storage in early 1950. Later that year, in November, the interest in the program has been revived. The outbreak of the Korean War caused Britain and the United States to re-examine the seaplane jet fighter. However, it was soon realized that the concept was outdated compared to the fast-advancing jet fighters of the day and the project was eventually cancelled.

How the British made a jet fighter and a flying boat
Serial number TG263 was the only surviving prototype (public domain)

In June 1951, the surviving Saunder-Roe SR.A/1 prototype flew for the last time. Today it is on display at the Solent Sky Museum in Southampton, UK.