SR.45 Princess

The Saunders‑Roe SR.45 Princess was a post‑war British flying‑boat designed to carry luxurious transatlantic passengers. Conceived in the late 1940s by the aircraft builder Saunders‑Roe, the Princess was intended to replace the wartime Short S.25 Sandringham and to compete with emerging land‑based airliners such as the Lockheed Constellation. Its first flight took place on 16 August 1949 from the company’s Cowes, Isle of Wight, facility. The aircraft featured a massive 12‑passenger cabin, five Rolls‑Royce Merlin piston engines driving four‑bladed propellers, and a distinctive double‑decker hull with a high‑mounted wing and a T‑tail. Hydraulic retractable landing gear permitted water and land operations, while the pressurised cabin offered unprecedented comfort for long‑range flights. Only two prototypes were completed before the program was cancelled in 1952, largely due to the rapid growth of jet airliners and the high operating costs of large flying‑boats. Despite its short lifespan, the Princess demonstrated the technical limits of piston‑engine flying‑boats and remains a symbol of British ambition in post‑war commercial aviation, influencing later seaplane designs and preserving the legacy of Saunders‑Roe’s innovative engineering. The surviving airframe is kept at the Royal Air Force Museum Cosford, serving as a tangible reminder of this ambitious era.