The Saunders-Roe SR.45 Princess was a British

flying boat A flying boat is a type of fixed-winged seaplane with a hull, allowing it to land on water. It differs from a floatplane in that a flying boat's fuselage is purpose-designed for floatation and contains a hull, while floatplanes rely on fuselag ...

aircraft developed and built by

Saunders-Roe Saunders-Roe Limited, also known as Saro, was a British aero- and marine-engineering company based at Columbine Works, East Cowes, Isle of Wight. History The name was adopted in 1929 after Alliott Verdon Roe (see Avro) and John Lord took a ...

at their

Cowes Cowes () is an English seaport town and civil parish on the Isle of Wight. Cowes is located on the west bank of the estuary of the River Medina, facing the smaller town of East Cowes on the east bank. The two towns are linked by the Cowes Fl ...

facility on the

Isle of Wight The Isle of Wight ( ) is a county in the English Channel, off the coast of Hampshire, from which it is separated by the Solent. It is the largest and second-most populous island of England. Referred to as 'The Island' by residents, the Is ...

. It has the distinction of being the largest all-metal flying boat to have ever been constructed. The Princess had been developed to serve as a larger and more luxurious successor to the pre-war commercial flying boats, such as the Short Empire. It was intended to serve the transatlantic route, carrying up to 100 passengers between

Southampton Southampton () is a port city in the ceremonial county of Hampshire in southern England. It is located approximately south-west of London and west of Portsmouth. The city forms part of the South Hampshire built-up area, which also covers Po ...

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and ...

and

New York City New York, often called New York City or NYC, is the List of United States cities by population, most populous city in the United States. With a 2020 population of 8,804,190 distributed over , New York City is also the L ...

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country Continental United States, primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., ...

in spacious and comfortable conditions. To achieve this, it was decided early on to make use of newly developed

turboprop A turboprop is a turbine engine that drives an aircraft propeller. A turboprop consists of an intake, reduction gearbox, compressor, combustor, turbine, and a propelling nozzle. Air enters the intake and is compressed by the compressor. ...

technology, opting for the

Bristol Proteus The Bristol Proteus was the Bristol Engine Company's first mass-produced gas turbine engine design, a turboprop that delivered just over 4,000 hp (3,000 kW). The Proteus was a reverse-flow gas turbine. Because the second turbine dro ...

engine still in development to power the aircraft. The project suffered delays due to difficulties encountered in the development of the Proteus engine. On 22 August 1952, the first prototype Princess, ''G-ALUN'', conducted its

maiden flight The maiden flight, also known as first flight, of an aircraft is the first occasion on which it leaves the ground under its own power. The same term is also used for the first launch of rockets. The maiden flight of a new aircraft type is alw ...

. Between 1952 and 1954, the first prototype performed a total of 47 test flights, including two public appearances at the

Farnborough Airshow The Farnborough Airshow, officially the Farnborough International Airshow, is a trade exhibition for the aerospace and defence industries, where civilian and military aircraft are demonstrated to potential customers and investors. Since its fir ...

. This work was carried out under a development contract for the

Ministry of Supply The Ministry of Supply (MoS) was a department of the UK government formed in 1939 to co-ordinate the supply of equipment to all three British armed forces, headed by the Minister of Supply. A separate ministry, however, was responsible for airc ...

, the intention being that this would lead to a contract for the aircraft from British

flag carrier A flag carrier is a transport company, such as an airline or shipping company, that, being locally registered in a given sovereign state, enjoys preferential rights or privileges accorded by the government for international operations. Hi ...

British Overseas Airways Corporation British Overseas Airways Corporation (BOAC) was the British state-owned airline created in 1939 by the merger of Imperial Airways and British Airways Ltd. It continued operating overseas services throughout World War II. After the pass ...

(BOAC). Although the initial development contract had been successfully met, BOAC eventually decided to focus on its land-based routes using the jet-powered De Havilland ''Comet'' instead. The era of the large flying boat had effectively ended prior to the aircraft's completion. Work on the Princess was ultimately cancelled after having produced three examples, only one of which flew. By the mid-1950s, large commercial flying boats were being increasingly overshadowed by land-based jet

airliner An airliner is a type of aircraft for transporting passengers and air cargo. Such aircraft are most often operated by airlines. Although the definition of an airliner can vary from country to country, an airliner is typically defined as an ai ...

s. Factors such as

runway According to the International Civil Aviation Organization (ICAO), a runway is a "defined rectangular area on a land aerodrome prepared for the landing and takeoff of aircraft". Runways may be a man-made surface (often asphalt, concrete ...

and

airport An airport is an aerodrome with extended facilities, mostly for commercial air transport. Airports usually consists of a landing area, which comprises an aerially accessible open space including at least one operationally active surfa ...

improvements had added to the viability of land-based aircraft, which did not have to compromise to accommodate the additional weight and drag of the boat hulls that were necessary on seaplanes, or the mitigating measures needed against the

corrosion Corrosion is a natural process that converts a refined metal into a more chemically stable oxide. It is the gradual deterioration of materials (usually a metal) by chemical or electrochemical reaction with their environment. Corrosion engi ...

caused by seawater. Following the project's termination, the three airframes were stored with the intention of selling them on; however, upon receipt of a promising offer for the aircraft, it was found that corrosion had set in while in storage. As a result, all three aircraft prototypes were subsequently scrapped.

Development

Origins

Before the

Second World War World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposi ...

, British airline

Imperial Airways Imperial Airways was the early British commercial long-range airline, operating from 1924 to 1939 and principally serving the British Empire routes to South Africa, India, Australia and the Far East, including Malaya and Hong Kong. Passengers ...

had successfully used large long-range passenger

s such as the Short Empire and

Short S.26 The Short S.26 G-class was a large transport flying boat designed and produced by the British aircraft manufacturer Short Brothers. It was designed to achieve a non-stop transatlantic capability, increasing the viability of long distant servic ...

to build up a network of long-distance routes. These flying boats had not only pioneered new aerial routes across the

British Empire The British Empire was composed of the dominions, colonies, protectorates, mandates, and other territories ruled or administered by the United Kingdom and its predecessor states. It began with the overseas possessions and trading posts e ...

which had previously not been served at all, passengers were transported within an unprecedented level of comfort, being provided with luxurious first class accommodation, including a

promenade An esplanade or promenade is a long, open, level area, usually next to a river or large body of water, where people may walk. The historical definition of ''esplanade'' was a large, open, level area outside fortress or city walls to provide cl ...

, sizable

galley A galley is a type of ship that is propelled mainly by oars. The galley is characterized by its long, slender hull, shallow draft, and low freeboard (clearance between sea and gunwale). Virtually all types of galleys had sails that could be u ...

, separate bathrooms for men and women, and individual cabins for passengers. However, operations of these flying boats had been disrupted by wartime, during which Imperial Airways had also merged with British Airways Ltd to form

(BOAC) in 1940.Kaplan 2005, pp. 196–197. While restricted operations of commercial flying boats did continue, such as the use of Boeing 314s for the transatlantic route, many were requisitioned for service with the

Royal Air Force The Royal Air Force (RAF) is the United Kingdom's air and space force. It was formed towards the end of the First World War on 1 April 1918, becoming the first independent air force in the world, by regrouping the Royal Flying Corps (RFC) an ...

(RAF) where they were typically used as

maritime patrol aircraft A maritime patrol aircraft (MPA), also known as a patrol aircraft, maritime reconnaissance aircraft, or by the older American term patrol bomber, is a fixed-wing aircraft designed to operate for long durations over water in maritime patrol ro ...

.Kaplan 2005, p. 196. During the pre-war era, flying boats had been preferred for conducting long-distance flights as, unlike their land-based counterparts, they were not limited by available runway length – the majority of which were still grass-surfaced at this point – and as a long range aeroplane would be required to carry a large load of fuel, a larger size of the aircraft could be permitted without needing to cater for factors such as limited runway and airfield sizes. In addition, for services to far-flung parts of the British Empire, the ability to land and take-off from any available area of water was a distinct advantage for services to such places, many of which at the time had no airport facilities at all. With the end of the Second World War, flying boats services were resumed with other types being operated, such as the Short Hythe,

Short Sandringham The Short S.25 Sandringham is a British civilian flying boat designed and originally produced by Short Brothers. They were produced as conversions of the prolific Short Sunderland, a military flying boat that was commonly used as a maritime ...

, and Short Solent. However, the war had also produced a legacy of large runways and sizable airports formerly used for military purposes that could now meet the needs of a larger generation of land aircraft.Kaplan 2005, pp. 197, 200, 204. Even prior to the war's end, the British

Air Ministry The Air Ministry was a department of the Government of the United Kingdom with the responsibility of managing the affairs of the Royal Air Force, that existed from 1918 to 1964. It was under the political authority of the Secretary of Stat ...

was enthusiastic on the prospects for reviving the shuttered flying boat routes.Kaplan 2005, p. 200. The Ministry approached two British flying boat manufacturers –

(Saro) and

Shorts Shorts are a garment worn over the pelvic area, circling the waist and splitting to cover the upper part of the legs, sometimes extending down to the knees but not covering the entire length of the leg. They are called "shorts" because they ...

– requesting that the two firms collaborate on the development and manufacture of a new aircraft, which would emerge as the

Short Shetland The Short Shetland was a British high-speed, long-range, four-engined flying boat built by Short Brothers at Rochester, Kent for use in the Second World War. It was designed to meet an Air Ministry requirement (defined in Specification R.14/40 ...

. As such, Saunders-Roe designed the Shetland and manufactured the wing while Shorts produced the remainder of the aircraft. While two examples of the Shetland were completed, the project was considered a failure and the pair of flying boats were scrapped in 1951. Saunders-Roe considered the Shetland to have not resembled the flying boat that they sought to develop, but was otherwise a useful learning experience; even prior to the Shetland, the company had wanted to develop a more revolutionary flying boat. During 1943, the chief designers of Saunders-Roe and Short had collaborated to produce a preliminary design specification for an innovative large flying boat.Kaplan 2005, p. 204. This design specification defined various criteria for the proposed aircraft, which would be the largest all-metal flying boat ever built; performance criteria included a weight of 140 tons, a

pressurised {{Wiktionary Pressurization or pressurisation is the application of pressure in a given situation or environment. Industrial Industrial equipment is often maintained at pressures above or below atmospheric. Atmospheric This is the process by ...

'double-bubble' hull, a 214-foot wingspan, a height of 55 feet 9 inches, and a length of 148 feet. The proposed aircraft would be capable of a cruising speed of 340 MPH at an altitude of 37,000 feet, a range (dependent on payload) of 5,190–3,640 miles, and be outfitted with luxurious accommodation for a total of 104 passengers.

Selection and delays

During 1945, in response to an approach made by the British

, which had been seeking design submissions from aviation companies for an envisioned new long range civil flying boat, which was to operate in BOAC's fleet to operate its transatlantic passenger services, Saunders-Roe decided to submit a bid based upon the earlier collaborative design specification. Following evaluations of a range of different propulsion methods and configurations, the design team selected the undeveloped

– one of the first

engines – to meet the enormous power requirements of the proposed giant flying boat. In May 1946, the bid made by Saunders-Roe was selected as the winner, leading to the company receiving an order for the production of three ''SR.45'' flying boats. Work on the SR.45 commenced almost immediately upon receipt of the order. From an early stage in development, progress on the programme was subject to schedule overruns and higher than projected costs being incurred, leading to scepticism of the flying boat's viability within the

House of Commons The House of Commons is the name for the elected lower house of the bicameral parliaments of the United Kingdom and Canada. In both of these countries, the Commons holds much more legislative power than the nominally upper house of parliament. T ...

, which was being increasingly regarded as a high-risk initiative with unreliable costing. Specifically, designing and testing of the airframe, as well as the independently conducted development of the Proteus engine to power the SR.45, had been major contributors to the higher-than-expected costs. In 1951, BOAC re-evaluated its standing requirements, and determined that the airline presently had no need for the Princess, or any new large flying boat. The airline had already elected to terminate its existing flying boat services during 1950. In late 1951, it was announced that construction of the three Princesses would proceed with the intention of using them as transport aircraft in RAF service. However, in March 1952, it was announced that while the first prototype would be completed, the second and third would be suspended to await more powerful engines.

Flight testing

On 22 August 1952, the prototype, ''G-ALUN'', conducted its

, piloted by

Geoffrey Tyson Geoffrey Arthur Virley Tyson FRAeS OBE (4 February 1907 – 9 January 1987) was an RAF officer, barnstormer and test pilot. He is best known for his aerobatic skills and the test flying of the Saunders-Roe SR.A/1 and Princess flying boats. Ear ...

.Kaplan 2005, p. 205. The initial flight lasted for 35 minutes, in which the flying boat performed a complete circumnavigation of the

. According to aviation author Phillip Kaplan, the Princess had not been intended to fly that day at all and only taxiing tests had been scheduled to take place, and that Tyson had decided to proceed due to the excellent conditions present on the day. The prototype was quickly put through several test flights with the hope of being able to sufficiently ready the flying boat to appear at the 1952

, however indications of engine reliability issues were encountered and this led to the intended flight display at Farnborough that year being abandoned. As further testing of the prototype continued, the reliability of the engines and

gearboxes Propulsion transmission is the mode of transmitting and controlling propulsion power of a machine. The term ''transmission'' properly refers to the whole drivetrain, including clutch, gearbox, prop shaft (for rear-wheel drive vehicles), differe ...

continued to be problematic, but not to the extent that flight testing was prevented. Evaluation of the flying boat continued into 1953, during which particular attention was devoted towards addressing the difficulties uncovered. During the 1953 Farnborough Airshow, the prototype was displayed. Flight tests of the prototype continued up until 27 May 1954, by which point it had been found that the Proteus engine, once perfected, would be capable of enabling the type to achieve its envisioned performance figures. ''G-ALUN'' was the only model to fly, performing 46 test flights in total during which 100 hours flight hours were accumulated. Princess Air Transport Co Ltd was formed with the object of studying the factors affecting the operation of the Princess flying boats and to tender for their operation should the opportunity have arisen. The company's directors were M D N Wyatt (chairman),

Sir Archibald Philip Hope, 17th Baronet Group Captain Sir Archibald Philip Hope, 17th Baronet, (27 March 1912 – 12 July 1987) was a Scottish aristocrat and aviator who flew with the Royal Air Force during the Second World War. Early life and education Archibald Philip Hope, known f ...

, Geoffrey Tyson, P D Irons and Capt H W C Alger (general manager). 75 per cent of the share capital were held by Saunders-Roe Ltd and the balance by

Airwork Airwork is an aviation business based in Auckland, New Zealand. The Airwork Group is New Zealand's largest general aviation company. It focuses on fixed wing and helicopter maintenance, leasing, and operations working with private and public e ...

Ltd.

Termination of production

Following the completion of flying tests performed by the prototype, the British government exercised considerable indecision over the fate of the programme. In addition to the prototype, a further two Princesses (''G-ALUO'' and ''G-ALUP'') were under construction, but these would ultimately never fly. While a decision from the government was effectively pending, the three existing aircraft were placed into storage, being cocooned and retained, one at Cowes and two at

Calshot Spit Calshot Spit is a one-mile long sand and shingle bank, near the village of Calshot, located on the southern bank of the open end of Southampton Water, on the south coast of England.OS Explorer Map, New Forest, Scale: 1:25 000.Publisher: Ordnan ...

; it had been hoped that work on the programme would be restarted when a buyer was found. Over the ensuing years, several offers were issued with the intention of purchasing the Princesses, including two proposals which would have involved re-engining them with

Rolls-Royce Tyne The Rolls-Royce RB.109 Tyne is a twin-shaft turboprop engine developed in the mid to late 1950s by Rolls-Royce Limited to a requirement for the Vickers Vanguard airliner. It was first test flown during 1956 in the nose of a modified Avro Linc ...

s. In 1954,

Aquila Airways Aquila Airways was a British independentindependent from government-owned corporations airline, formed on 18 May 1948 and based in Southampton, Hampshire. History Aquila was founded by Barry Aikman, initially using two converted Royal Air For ...

had offered £1 million each for the stored Princesses, but this offer was rejected. In 1957, Saro itself had proposed the conversion of the aircraft to serve as landplane troop carriers/freighters. In 1964, the three Princesses were all purchased by Eoin Mekie on behalf of

Aero Spacelines Aero Spacelines, Inc. was an American aircraft manufacturer from 1960 to 1968 that converted Boeing 377 Stratocruisers into the famous Guppy line of airplanes, re-engineered to transport oversized cargo such as space exploration vehicles. ...

, who planned to use them as heavy-duty freight aircraft for transporting

Saturn V Saturn V is a retired American super heavy-lift launch vehicle developed by NASA under the Apollo program for human exploration of the Moon. The rocket was human-rated, with multistage rocket, three stages, and powered with liquid-propellant r ...

rocket components for

NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeedin ...

. When the cocooning was removed, it was found that they were badly corroded (the contract for maintenance and inspection of the stored aircraft had been allowed to lapse, which resulted in the airframes deteriorating rapidly), and all three Princesses were broken up by 1967. They were the last fixed-wing commercial aircraft produced by Saunders-Roe. The company constructed one more fixed-wing design, the Saunders-Roe SR.53 mixed-power (rocket and turbojet) fighter design; aside from that venture, the company primarily concentrated its efforts on

helicopter A helicopter is a type of rotorcraft in which lift and thrust are supplied by horizontally spinning rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forward, backward and laterally. These attribu ...

s and

hovercraft A hovercraft, also known as an air-cushion vehicle or ACV, is an amphibious craft capable of travelling over land, water, mud, ice, and other surfaces. Hovercraft use blowers to produce a large volume of air below the hull, or air cushion, ...

after this point.

Proposals for reuse

In 1958, information on the Princess was shared with the

United States Navy The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage ...

, who were at the time examining the possibility of converting the three stored aircraft to make use of

nuclear power Nuclear power is the use of nuclear reactions to produce electricity. Nuclear power can be obtained from nuclear fission, nuclear decay and nuclear fusion reactions. Presently, the vast majority of electricity from nuclear power is produced b ...

."U.S. Given Data on Flying-Boats – Use of Nuclear Power". ''

The Times ''The Times'' is a British daily national newspaper based in London. It began in 1785 under the title ''The Daily Universal Register'', adopting its current name on 1 January 1788. ''The Times'' and its sister paper '' The Sunday Times'' ( ...

'', Monday 3 February 1958, Issue 54065. p. 5, column A. This interest resulted in a delegation from Saro being dispatched to the US for the purpose of discuss a sale of the preserved Princesses. However, this interest ultimately amounted to nothing. In the wake of the success of his

Pregnant Guppy The Aero Spacelines Pregnant Guppy was a large, wide-bodied cargo aircraft built in the United States and used for ferrying outsized cargo items, most notably components of NASA's Apollo program. The Pregnant Guppy was the first of the Guppy ...

, constructor Jack Conroy discussed his concepts for other outsize transports with ''Air Progress'' in their publication, ''World's Greatest Aircraft'' (Petersen Publications, 1973). Conroy considered the creation of an outsize transport from the Princess to have been basically feasible, in that it shares a sectional 'double-bubble' fuselage construction similar to that of the Boeing Model 377 Stratocruiser, on which the Guppies were based. The reason for considering producing such an aircraft was the desire of

to possess a means of transporting first stage of the

rocket by air, if this were possible, to

Cape Canaveral , image = cape canaveral.jpg , image_size = 300 , caption = View of Cape Canaveral from space in 1991 , map = Florida#USA , map_width = 300 , type = Cape , map_caption = Location in Florida , location ...

; the ability for the aircraft to conduct a water landing would also be advantageous for proximity landing at sea, or on nearby lakes in

Florida Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and ...

. Ultimately, this plan was deemed to be impractical, though the existing Guppies continued to function throughout the

Apollo Apollo, grc, Ἀπόλλωνος, Apóllōnos, label=genitive , ; , grc-dor, Ἀπέλλων, Apéllōn, ; grc, Ἀπείλων, Apeílōn, label=Arcadocypriot Greek, ; grc-aeo, Ἄπλουν, Áploun, la, Apollō, la, Apollinis, label= ...

program as efficient air transport of the outsize hardware used in these missions. Conroy quipped that the British were "offended when we named our aircraft 'The Pregnant Guppy'. Man, can you imagine what they would have said if we produced 'The Pregnant Princess' !"

Design

The SR.45 ''Princess'' was a large flying boat, being the largest all-metal flying boat to have ever been constructed. The Princess featured a rounded, bulbous, "double-bubble" pressurized

fuselage The fuselage (; from the French ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds crew, passengers, or cargo. In single-engine aircraft, it will usually contain an engine as well, although in some amphibious aircraft t ...

which contained two full passenger decks; these decks had sufficient room to accommodate up to 105 passengers in great comfort. The planing bottom of the hull had only a slight step in the keel to minimize drag in the air. The Princess was powered by an arrangement of ten

engines. These engines drove six sets of four-bladed

propellers A propeller (colloquially often called a screw if on a ship or an airscrew if on an aircraft) is a device with a rotating hub and radiating blades that are set at a pitch to form a helical spiral which, when rotated, exerts linear thrust upon ...

; of these, the inner four propellers were double,

contra-rotating propellers Aircraft equipped with contra-rotating propellers, also referred to as CRP, coaxial contra-rotating propellers, or high-speed propellers, apply the maximum power of usually a single piston or turboprop engine to drive a pair of coaxial propell ...

which were driven by a twin version of the Proteus, named the ''Bristol Coupled Proteus'', each engine drove one of the propellers. The two outer propellers were single and each powered by a single engine. The cockpit of the Princess was designed to be operated by a pair of pilots, two

flight engineer A flight engineer (FE), also sometimes called an air engineer, is the member of an aircraft's flight crew who monitors and operates its complex aircraft systems. In the early era of aviation, the position was sometimes referred to as the "air m ...

s, a

navigator A navigator is the person on board a ship or aircraft responsible for its navigation.Grierson, MikeAviation History—Demise of the Flight Navigator FrancoFlyers.org website, October 14, 2008. Retrieved August 31, 2014. The navigator's prima ...

, and a

radio operator A radio operator (also, formerly, wireless operator in British and Commonwealth English) is a person who is responsible for the operations of a radio system. The profession of radio operator has become largely obsolete with the automation of ra ...

. Early on, it had been intended for the aircraft to be outfitted with some form of powered flight controls, including an early

fly-by-wire Fly-by-wire (FBW) is a system that replaces the conventional manual flight controls of an aircraft with an electronic interface. The movements of flight controls are converted to electronic signals transmitted by wires, and flight control ...

implementation, in order that pilots would be able to effectively actuate its large control surfaces, which would have to overcome equally larger forces. However, it was decided to opt for a traditional mechanical linkage approach that was augmented by a series of electrically driven power assist units to effectively support actuation instead. The

aileron An aileron (French for "little wing" or "fin") is a hinged flight control surface usually forming part of the trailing edge of each wing of a fixed-wing aircraft. Ailerons are used in pairs to control the aircraft in roll (or movement around ...

s and

rudder A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, aircraft, or other vehicle that moves through a fluid medium (generally air or water). On an aircraft the rudder is used primarily to counter adve ...

were split into multiple sections in order that, if a part of the servo-powered control system were to fail, a faulty section could be "trailed" so that it did not act against the remaining working sections. While the prototype aircraft had been fitted with advanced (but conventional) hydraulic controls, Saunders-Roe had intended production aircraft to use an analogue system featuring electrical servos with hydraulic final control actuators. Such a system had been built and undergone ground-testing, but the Princess had been terminated prior to any aircraft having been fitted with the system.

Specifications

References

Citations

Bibliography

* * * * * Kaplan, Philip
"Big Wings: The Largest Aeroplanes Ever Built."
Pen and Sword, 2005. . * * *
"Ten Turboprops Power Giant Flying Boat."
''Popular Science,'' August 1949.

''Flight'', 7 December 1951, p. 724. * *

External links

Video on Youtube

"Britain's Biggest Flying Boat," ''Popular Mechanics,'' September 1948
{{Saro aircraft

Princess Princess is a regal rank and the feminine equivalent of prince (from Latin '' princeps'', meaning principal citizen). Most often, the term has been used for the consort of a prince, or for the daughter of a king or prince. Princess as a subs ...

1950s British airliners Flying boats Ten-engined six-prop tractor aircraft Six-engined turboprop aircraft Aircraft with contra-rotating propellers High-wing aircraft Cancelled aircraft projects Aircraft first flown in 1952