No. 44. Saunders-Roe SR.45 Princess (G-ALUN c/n SR.901)
Photographed at East Cowes, Isle of Wight, UK

Saunders-Roe SR.45 Princess

09/20/2002. Remarks by Ron Dupas: given to me by a highschool friend, Dwight Thomas, who received it from a pen-pal, the young man standing by the fence.

02/11/2003. Remarks by Des Nicholas: "This photograph shows one of the three Saunders-Roe Princess Flying Boats cocooned at Cowes just across the river Medina from where they were built at East Cowes. The other two were stored at Calshot near Southampton waiting for possible buyers. When none were found all three were broken up.

I was lucky enough to see Princess G-ALUN take off on it's first flight in 1952 when I was twelve. My brother and I had gone down to watch what we had been told would be taxiing trials. After a short time taxiing the aircraft swung into wind and took off. At the time the only aircraft of similar size were the Bristol Brabazon and Hughes' 'Spruce Goose'. As kids we were highly impressed, the aircraft made a wonderful noise probably somewhat like a B-36.

My godfather Harold Palmer was one of the flight observers during the tests of G-ALUN, the only Princess to fly.

This photograph brought back many memories: we used to pass this aircraft after crossing from East Cowes to Cowes or back again on the floating bridge. I remember that as we used to pass by, the plane did not appear to look particularly big although at the time it was as big as they got, weighing about 140 tons. The quay that the Princess was stored at had previously been Thetis yard and dry dock that Thomas White, father of John Samuel White, the Cowes shipbuilder, had constructed in 1815 to repair ships up to 800 tons. It had also been used to store Sunderland flying boats and Walrusses. The Sunderland used to test the Princess's flying control system and one of the Saro SRA1 (Squirt) jet flying boats was also there for a while."

04/14/2003. Remarks by Colin Urry: "This photo shows G-ALUN on the slip at Cowes. One of the reasons that all 3 boats were around for so long was that NASA had indicated an interest in using them on a program to test an airborne nuclear powerplant. Imagine that bellying into Heathrow!"

01/28/2005. Remarks by Dave de Bourcier: "On August 22, 1952 I was stationed, as a National Serviceman, at RAF Calshot, learning "a trade" prior to being posted to 1103 Section, Air Sea Rescue, Felixstowe. On that day all of our boats, pinnaces, crash-boats, and fire-boats were stationed along an approximately five mile stretch of the Solent, north of Cowes, in case of misadventure during the first trial-taxi and/or flight of the Princess Flying Boat.

I recall that as the great aircraft made it's run in front of us a Sunderland taxied beneath each great wing right up to the point of take-off. I assume they were collecting technical data about what was taking place. The Princess did successfully take off and did complete one circuit, probably around the coast of the Isle of Wight, and then landed.

I'm not sure if it ever took off again, but within a few short weeks, while I was yet at Calshot, one of the three Princesses that were built (I'm not sure if it was the one that flew) was hauled up on the slip at Calshot. Special winches were installed into the slipway in order to accomplish this. The aircraft was secured on the end of the spit, with one wing right overhanging the old Calshot tower, and there it was mothballed.

When I returned to England, on holiday in 1960, as the m.v. "Italia" steamed up the Solent en route to Southampton, the Princess was still sitting there at the end of Calshot Spit. How very sad."

04/30/2011. Remarks by Johan Visschedijk: "H. Knowler of the Saunders-Roe Ltd. began design of the Princess originally in 1943, as an extension of the company's ideas for a large long-range commercial flying boat. In July, 1945, the company was invited by the Ministry of Supply to tender for the construction of an aircraft of this type, and in May, 1946, the Minister of Supply, George Strauss, authorized construction of three flying boats. At that time British Overseas Airways Corporation (BOAC) had signified their interest in the project, envisaging its use on the direct London-New York route. The three aircraft, c/n SR.901 to SR.903, were registered to the MoS as G-ALUN, G-ALUO and G-ALOP on October 15, 1949.

Early in 1951, BOAC, by then fully committed to landplane operations, decided not to operate the Princess. Thereupon it was officially announced that the three Princesses being built would be completed for the RAF as long-range military transports. In March, 1952, a further official pronouncement declared that the first Princess, powered by ten Proteus 600 engines, would be completed, but that work on the second and third boats would be temporarily stopped to await production of the more powerful Proteus 700 Series engines for which the Princess was designed, and to release capacity for more urgently-needed construction.

The first Princess, powered by ten Bristol Proteus 600 Series engines was flown by a fourteen-men crew (led by Geoffrey Tyson) for the first time on August 22, 1952. In 1953 it was confirmed that flight trials, to include pressurized flights at 30,000 ft (9,150 m), were to proceed up to a total of 100 hours on the first aircraft. The preliminary flight trial program was completed in 1954, when it was decided to suspend further flying until after the installation of more suitable engines, as the trials fully justified expectations in all respects.

Engine technology had had progressed rapidly and the MoS, Saunders-Roe and Bristol tried to agree on how to install six of Bristol's new Orion turboprop. No agreement was forthcoming and all three aircraft were cocooned. Over the next ten years a number of possible buyers emerged (the three aircraft were deregistered in December 1963 as "Change of ownership to Bahamas company") but none took delivery of the aircraft and by 1967 all three had been scrapped.

TYPE. Long-range transport flying boat with accommodation for up to 220 passengers.
WING. High-wing cantilever monoplane. All-metal two-spar structure in five main units: centre wing, two inner wings, and two outer wings. Electrically-operated slotted flaps on centre and inner wings. Electro-hydraulic mechanical power-controlled four-piece ailerons in each outer wing. Thermal anti-icing, to wing leading-edges and air intakes is provided.
HULL. Two-step metal structure. "Double-bubble" arrangement providing two main decks. Pressurised from forward of flight deck to tail breakdown joint aft; pressure differential 8 lb/ (56.2 kg/sq.m). Pressurization by tappings from main engine compressors. Retractable wing-tip floats.
TAIL UNIT. Cantilever monoplane type. Dihedral tailplane. Electro-hydraulic mechanical power-controlled rudder in three sections and elevators in two sections each. Tail-unit thermal anti-icing by self-contained kerosene combustion heaters with independent fuel supply and electric ignition from cockpit.
POWERPLANT. Ten Bristol Proteus 600 Series turboprop engines, each producing 3,200 shp plus 800 lb (363 kg) jet thrust. Eight engines coupled in four pairs and two single units. Fuel in two integral tanks in each inner wing between engine bays. Total capacity 17,414 gal (65,918 l).

Created 1998-2001