Летающая лодка A.33 проектировалась согласно спецификации министерства авиации R.2/33, по этой же спецификации была разработана Short Sunderland. В 1938 году компания «Saunders-Roe» установила на Saro A.33 крыло Monospar; силовая
установка A.33 состояла из четырех смонтированных над крылом моторов Bristol Perseus XII мощностью по 830 л. с. По схеме лодка представляла собой моноплан-парасоль, дополненный развитыми спонсонами корпуса. В ходе испытаний на руление по водной поверхности летающая лодка получила повреждения и была разобрана.
SAUNDERS-ROE A.33. A British flying-boat which has long intrigued students of aircraft development is the little-known Saunders-Roe A.33 of the late 1930s. For the first time, Air Pictorial publishes a three-view drawing together with a number of hitherto unpublicised details.
The Saro A.33 was built to the same Air Ministry Specification (R.2/33) as the Short Sunderland - calling for a long-range reconnaissance and patrol flying-boat. The contract for one prototype (K4773) was placed in 1934-35 and construction started late in 1936. The A.33 was completed in September 1938 and the first taxi-ing trials were carried out on 10th, 11th and 12th October. On 14th October the A.33 was airborne for the first time, at an all-up-weight of 31,000 lb. After some half a dozen flights, K4773 was seriously damaged through "porpoising" during high-speed taxi-ing in the Solent. As the result of a heavy hull/water impact, the fabric-covered, all-metal wing failed in torsion at a position in line with the inner starboard Perseus. The starboard wing then twisted about the single main spar and the starboard inner airscrew ripped into the hull and sponson, while detached structure damaged the tail assembly. As the damage was above the water-line, the A.33 did not sink and it was towed back to the East Cowes slipway.
This unique British example of the sponson flying-boat was not repaired and Saro concentrated on the twin-engined A.36 Lerwick.
SAUNDERS-ROE A.33. The A.33 was powered by four 830-h.p. Bristol Perseus XII sleeve-valve radial engines and had a design max. speed of 200 m.p.h. at sea-level. Gross weight (design) was 41,500 lb., and on at least one occasion the A.33 was flown at 35,000 lb. Nose and tail power-operated turrets were to have been fitted, while pillar-mounted single .303-in. Vickers K machine guns were to be fitted each side of the enclosed dorsal hatchway just forward of the single fin. The wing was supported by massive N-struts attached to the metal sponsons and by V-struts attached to the hull. Other data: Not known.