RogerBW's Blog

Saunders-Roe Princess 12 June 2014

The Saunders-Roe SR.45 Princess was the largest all-metal flying-boat ever built. Only three were made, and none was ever sold.

The project was started by the Ministry of Supply immediately after the Second World War, when it invited Saunders-Roe to bid for a new long-range flying-boat for BOAC. Work began in 1946.

By 1951, BOAC decided it had no need for the aircraft, but Saunders-Roe continued construction as a transport plane for the RAF. By the next year, clearly, the RAF had expressed its lack of interest; only one of the three prototypes was to be completed (indeed, it flew that year) and work on the others was to be paused.

The huge aircraft had ten Bristol Proteus engines in six mounts, driving ten propellers (the inner four being contra-rotating pairs). The pressurised fuselage contained two passenger decks, with room for 105 passengers in extreme comfort. Predicted range was about 5,000 nautical miles at 313 knots, enough to cross the Atlantic in perhaps ten hours and reach most of the inhabited world in a single hop.

Princess Air Transport was formed as a subsidiary of Saunders-Roe to look for a use for the things, but nothing came to light, and all three aircraft were coccooned. Various plans were hatched, including re-engining with jets, conversion to landplane troop carriers, driving the propellers with an on-board nuclear reactor (that was the US Navy, of course, in response to the USAF's NB-36H experiments), and even (in 1964) to use them as heavy freighters to transport Saturn V rocket components. However, it seems that preservation had not been as effective as hoped, and all three airframes were badly corroded and unusable; they were all broken up by 1967.

In effect, the long-range flying-boat was dead, killed by improvements to airfields. Flying-boats could never fly as efficiently as land-based aircraft because of the aerodynamic compromises needed for a boat hull, and were subject to seawater corrosion and the need for calm water (though at this size it was probably more tolerant than most of rough conditions).

The follow-up aircraft, the Duchess, which would have been slightly smaller and powered by six de Havilland Ghost turbojets, never got off the drawing-board.


  1. Posted by Owen Smith at 01:59pm on 12 June 2014

    It was WWII that put an end to the flying boat era. All that money spent on long runways for bombers. Left to commercial pressures these runways may never have been built, and certainly planning issues would have been greater. Planning Permission was pretty much ignored for war purposes.

  2. Posted by RogerBW at 02:06pm on 12 June 2014

    At the European and American end of things, yes. But there were plenty of places, for example in colonial Africa, where airfields took a bit longer to catch up, and I suspect that that gap is why the Ministry of Supply thought the project worth doing at all.

  3. Posted by John Dallman at 04:20pm on 15 June 2014

    Until they finally grasped that thee wasn't all that much money in routes to the (ex-) colonies, as compared to places where people went for large-scale business or holidays.

  4. Posted by Owen Smith at 05:52pm on 29 June 2014

    The routes were also a problem for the VC10. Designed for BOAC specifically for "Hot and High" colonial airports, there just wasn't the travel demand to go there. And the extra stiff wings and other design features for hot and high meant it wasn't economical on mainstream routes.

Comments on this post are now closed. If you have particular grounds for adding a late comment, comment on a more recent post quoting the URL of this one.

Search
Archive
Tags 1920s 1930s 1940s 1950s 1960s 1970s 1980s 1990s 2000s 2010s 3d printing action aeronautics aikakirja anecdote animation anime army astronomy audio tech base commerce battletech beer boardgaming bookmonth chain of command children chronicle church of no redeeming virtues cold war comedy computing contemporary cornish smuggler cosmic encounter coup cycling dead of winter doctor who documentary drama driving drone ecchi espionage essen 2015 essen 2016 essen 2017 existential risk falklands war fandom fantasy film firefly first world war flash point food garmin drive gazebo geodata gurps gurps 101 harpoon historical history horror hugo 2014 hugo 2015 hugo 2016 hugo 2017 hugo-nebula reread in brief avoid instrumented life kickstarter learn to play leaving earth linux mecha museum mystery naval non-fiction one for the brow opera perl photography podcast politics powers prediction privacy project woolsack pyracantha quantum rail ranting raspberry pi reading reading boardgames social real life restaurant reviews romance rpg a day rpgs science fiction scythe second world war security shipwreck simutrans south atlantic war squaddies stationery steampunk stuarts suburbia superheroes suspense television the resistance thirsty meeples thriller tin soldier torg toys trailers travel vietnam war war wargaming weather wives and sweethearts writing about writing x-wing young adult
Special All book reviews, All film reviews
Produced by aikakirja v0.1