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Saro designations


ACCESS: Secret
Mar 24, 2008
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Hi all

(from Putnam)


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Senior Member
May 26, 2006
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P.100 recce/observation flying boat
P.103 seaplane jet fighter
P.111 amphibian based on Princess
P.112 six-engined large flying boat
P.117 V-tail flying boat
P.123 four-engined flying boat
P.124 V-tail twin-engined amphibian
P.125 four-engined flying boat
P.126 160-seat stretched Princess
P.127 seaplane jet fighter
P.129 V-tail flying boat
P.130 was the same designation SR.44
P.132 four-engined low-wing airliner (studied with Folland)
P.136 four-engined flying boat
P.139 200-seat four-engined airliner
P.141 seaplane jet fighter
P.142 ,, ,, ,,
P.145 Princess variant with eight engines
P.153 helicopter project (no more details)
P.160 Car Ferry amphibain twin-boom freighter
P.164 Princess with ten to twelve engines
P.165 various engine schemes on Princess
P.166 400-seat large flying boat
P.171 low-wing light transport
P.173 numerous schemes for stretched re-engined Princess develoments
P.195 seven-seat VIP transport aircraft
P.199 landplane version of Princess
P.200 Unmanned hydrofoil ASW-torpedo carrier
P.201 ten-passenger executive aircraft based on SR.177
P.202 eight-seat executive aircraft based on SR.177
P.203 Princess derivative with six engines
P.206 floatplane developed from HDM.106
P.207 a development of HDM.106
P.208 amphibian flying boat
P.210 seaplane jet fighter
P.213 nuclear-powered flying boat
P.220 autogyro with high stub wing single-rotor transport

P.508 was light helicopter project
P.514 tandem-rotor 50-seat helicopter
P.539 high-wing VSTOL/STOL transport
P.541 five-seat helicopter powered by Blackburn engines


Senior Member
Jun 25, 2009
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Excellent, hesham. Thanks! I've also been doing my homework since yesterday, and I came up with other designations than yours, so here's a complete recap of what we have brought into the matter so far, which cancels previous versions.

Also please note that P.153 was not a helicopter, but a hydrofoil-equipped motor boat project.


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Senior Member
May 26, 2006
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Good work my dear Stargazer;

but you still have a more job,and from Tony Butler books;

P.113 was SR.44 to E6/44
P.114 long jet pipe version of P.113
P.151 high performance fighter 1951
P.155 delta-wing fighter 1952
P.161 mixed powerplant delta wing fighter 1952
P.167 a development of P.154
P.178 swept-wing naval strike aircraft 1954
P.179 delta-wing strike fighter 1954
P.180 supersonic interceptor 1954
P.209 a development of SR.53


Senior Member
Jun 25, 2009
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Thanks, hesham. Just found another one in my files:

P.193 was a 1956 proposal for an AEW Princess with a dorsal radome, sort of an AWACS ancestor.


Feb 10, 2009
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Fly Past IX'1996 monthly says that A.1 was Kittiwake, 2-engined biplane transport flying boat ;
A.5 was Vickers - Saunders Valentia, 2-engined biplane bomber - recco amphibian.


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Jun 25, 2009
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Boogey said:
Fly Past IX'1996 monthly says that A.1 was Kittiwake, 2-engined biplane transport flying boat ;
A.5 was Vickers - Saunders Valentia, 2-engined biplane bomber - recco amphibian.

Thanks a lot Boogey. "A.1" seems consistent since the Kittiwake was the first post-war design from Saunders.

I had already noted "A.5" for the Valentia, but wasn't sure if it wasn't a mistake because it goes against the chronology. Indeed, the Valentia was developed in 1921-22, while the lower numbers A.3 Valkyrie and A.4 Medina were both ordered in 1924 and flown in 1927 and 1926, respectively. If we consider FlyPast's data as correct, this could indicate that perhaps the allocation of designations to the first few designs might have been done retroactively at some point with no absolute coherence as to time sequence.

Another designation I found for the Valentia is "B.S.1", although I do not know what that stands for ("V.S." would have been more logical for a Vickers/Saunders design...).


Senior Member
Jun 25, 2009
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More Saro project designations (gleaned from the British Secret Projects books):

Military flying boat with pylon-mounted wing and two Bristol Centaurus 171 engines (1951)
P.106 Mixed powerplant four-engine military flying boat; two versions (V-tail with Griffon/Nene or twin-boom with Nomad/Sapphire) (1949-51)
P.110 Princess civil flying boat proposed as reconnaissance bomber (1950)
P.121 Hydro-ski fighter project with reheated Sapphire engine (1950)
P.188 Schemes for high-speed high-altitude reconnaissance aircraft developed to R.156T specification but was not an official tender (1955)


You're Mad, You Are.....
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May 1, 2007
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Saro fixed-wing postwar projects list, from Tagg/Wheelers 'From Sea to Air' :


P.100 1946-47
Schemes for conversion of the Auster VI and Heston A4/45 AOP to twin-float seaplanes. The Auster scheme was adopted and a prototype was converted and flown at Cowes.

P.103 1947
A swept wing version of the SR.A1 probably with AS Sapphires.

P.104 1948-53
Various schemes of flying boats in connection with MoS Spec.R2/48. 14 versions with weights ranging from 89,900 to 135,000 lb and wing spans from 134 ft to 168 ft included one version based on use of the Britannia wing. Tail units included versions with single fin and rudder, twin fin and rudder and V-type tail. All versions were four engined and included Centaurus, Turbo Griffons, compounded Griffons and Nomad. A retractable radar scanner in the underside was positioned in the nose or alternatively behind the wing.

P.105 1951
50,000 lb military flying boat with pylon-mounted wing.2 Bristol Centaurus 171. Hull lines and internal layout produced in some detail.

P.106 1949-51
Alternative versions of four-engined military flying boat with mixed power plant of compound piston engines and pure jets permitting high take-off weights and long range on the economic compound engines. First version with conventional hull and V-tail was powered by 2 compounded Rolls-Royce Griffons and 2 Rolls-Royce Nenes, included retractable radar scanner and downward firing rockets. 81,000 lb. 134 ft span. Second version with twin booms and tail floats was powered by 2 Napier Nomad and 2 AS Sapphire engines. 90,000 lb. 135 ft span.

P.108 1949
Two versions of a glider, the hull of which detached to serve as a lifeboat. The Mk.II version was favoured and the hull shape, jettison system and operational technique were investigated in some detail.

A 100,000 lb flying boat with 6 jet engines, probably Nene or Ghost, buried in a wide chord centre section. Not developed in detail.

P.110 1950
The SR.45 Princess proposed as a reconnaissance bomber.

P.111 1954
The SR.45 Princess proposed as an amphibian.

P.112 A 220,000 lb 215 ft span flying boat in two versions with either conventional or double bubble hull. 6 Napier Nomad driving contra-props.

P.117 1949
A 131,000 lb 162 ft span commercial flying boat with V-tail. Powered by 4 Napier Nomad driving contra-props.

P.121 1949-51
A single-seat swept-wing fighter with AS Sapphire engine with afterburning. Three alternative schemes with retractable bottom, ski undercarriage plus a wheeled trolley and version with wheeled undercarriage.

P.122 1949-50
Development of the SR.A1. A two-seater swept-wing flying boat fighter and a single-seater with straight wing with tapered leading edge. Both with AS Sapphire with afterburning.

P.123 1948-50
Two versions of 120,000 lb 148 ft span flying boat with 4 Bristol Centaurus 663 engines or 146 ft span with 4 Bristol Proteus turbo-props. A smaller version of 98,000 lb and 134 ft span was to be powered by 4 compounded Rolls-Royce Griffons and had twin fins and rudders.

A light twin-engined amphibian transport for 16 passengers and 2 crew. 2 AS Mamba turbo-props.

P.125 1948
Two versions of a flying boat for freight carrying with either a single hull with twin booms or twin fuselages. The power was provided by 4 Bristol Centaurus engines in coupled pairs driving contra-props.

A stretched version of the SR.45 Princess for 160 passengers. Increased in length by 26 ft 6 in to an AUW of 360,000 lb.

P.127 1949-50
Three versions of a single-seat flying boat for research purposes powered by a Metrovick Beryl jet engine. The first version with delta wing was followed by swept-wing and straight-tapered wing versions. The last version included schemes with retractable planing plates and undercarriage.

P.129 1949
A 157,375 lb passenger flying boat, 151 ft span, V-tail. 4 Bristol Proteus turbo-props.

P.131 1951
The Duchess swept-wing flying boat in long and short range versions with 6 Rolls-Royce Avons or 4 Napier Nomads driving contra-props. The V-tail and Nomad engines were discarded in favour of a swept single fin and rudder. Various versions with Avon engines, including an amphibious version, were schemed providing passenger accommodation varying from 38 to 106 in the troop-carrying version. AUW 150,000 lb. 145 ft span (141 ft in the trooper version).

P.132 1948-49
A landplane passenger transport in two versions in collaboration with Folland Aircraft. The first scheme was for 11 passengers plus pilot based on the use of 4 DH Gipsy Major X Mk.2. AUW 8,500lb. The second scheme employed DH Gipsy Queen II engines and accommodated 17 passengers and pilot. AUW 12,500 lb.

A flying boat schemed around the DH Comet wing and DH Ghost engines with afterburning. A landplane project covered by the same number is a basic DH Comet with the addition of 2 DH Sprite rocket motors between the jet engines.

P.135 1950
A six engined swept-wing flying boat on the same lines as P.131 but powered by DH Ghost engines, weighing 130,000 lb with wing span of 135 ft 6 in in the first scheme. Two later schemes were 4 engined machines using Ghosts with afterburning, both were based on an AUW of 107,980 lb with a wing span of 124 ft 6 in for carrying 40 - 70 passengers. One had a conventional swept wing but the alternative was most unconventional and was a canard with forward swept wing.

P.136 1950
A conventional 4 engined passenger flying boat powered by 4 Bristol Hercules 763 engines. AUW 82,000 lb. Wing span 118 ft 6 in.

P.138 1950-52
Versions of the SR.45 Princess with 12 DH Ghost or with 10 Rolls-Royce Avons and 2 RB.93 Jet Packs.

P.139 1950
A passenger landplane for 96 - 104 passengers on two decks, powered by 4 Napier Sabre VII engines. AUW 132,000 lb. Wing span 144 ft.

P.142 1950
Single seat water based fighters. The first a twin jet delta of 50 ft span. The second version, also with hydro-ski, was developed in more detail to show also a carrier based version with undercarriage and upward folding wings. The pilot was housed in a pod on the centre section and twin fuselages housed the 2 Napier E. 137 jet engines with afterburning and carried the fins and high-set tailplane.

P.145 1951
A version of the SR.45 Princess with 8 Napier Nomads driving contra-props.

P.147 1951-52
Four versions of the Sea Raider project consisting of a glider housing two motor boats. Weights ranged from 10,000 - 30,000 lb and wing spans from 60 ft to 110 ft. In addition the two motor boats ranged in weight from 8,200 lb to 24,150 lb. Straight and cranked wings were considered but all schemes incorporated V-tails and the main hull incorporated a marine propulsion system for use after jettisoning the wing and tail portions and discharging the motor boats and would be equipped with a gun turret. In the boats 2 125 HP Rover V-6 piston engines were initially employed, later Rover Gas Turbines were proposed.

P.148 1950
A two-seater fighter, land based in two versions and later with an alternative hydro-ski, all using Rolls-Royce Avon RA.10 or 14. Initially with a straight wing with tapered leading edge followed by a fully tapered wing and then a swept wing version. Weights varied from 20,400 to 28,000 lb. Pilot and navigator sat side by side and an internal air to air rocket battery was carried. The final version was schemed in some detail and was the subject of a tender to MOS Spec.N.114.T.

P.149 1951
Many schemes for a single seat fighter to Spec.ER.110.T which included delta, straight tapered and 60° LE swept wings with side by side engines at 27,000 lb AUW. Variable geometry wings wereschemed in some detail, initially at an AUW of 32,000 lb, ranging through a version with stacked engines at 28,000 lb to a preferred scheme with side by side installation. All versions used the Rolls-Royce Avon RA.12 with afterburning.

P.151 1951
This covered at least seven schemes for a high performance single seat fighter, including one for carriage to operational height by a turbo-prop aircraft with twin booms and central fuselage pod. Wings were generally tapered on leading and trailing edge but also included delta plan form. Conventional undercarriage, skid and hydro-ski landing gear were considered. A variety of power plants was considered. As many as 6 Rolls-Royce Jet Packs were mounted above the wing or at the wing tips and tail in various combinations. One version employed a Rolls-Royce Avon with 4Jet Packs and yet others employed additional rocket motors, including the DH Spectre.

P.152 1952
The short and long range versions of the P.131 Duchess were updated with a V-tail but otherwise were similar to the 1 50,000lb 145ft span machine previously schemed.

P.153 1952
Project for a hydrofoil equipped motor boat.

P.154 1950-52
This was the project which resulted in a proposal being submitted as an Addendum to the tender to MOS for F.124.T finally resulting in the order for the SR.53 by way of further developments under P.167. Various schemes were investigated and these included six delta wing and one swept wing project and a simple skid-landing type with short span tapered wing and propelled by a DH Spectre rocket motor. The designs of these were not developed in any great detail prior to arriving at the scheme proposed to MOS.

A high performance delta wing fighter on which little detail work was carried out.

A boat hull.

A helicopter vibration simulator.

P.160 1952
This covered four versions of a twin-boom freighter or car ferry amphibian aircraft powered by two Bristol Hercules 730 radial engines. P.160/1 & 2 had an AUW of 42,000 lb and P.160/3 & 4 47,000 lb and both offered alternative undercarriages with hydro-ski surfaces or conventional type balancing floats.

P.161 1952
A delta wing fighter with mixed power plant schemed in heavy and light weight versions. The first was powered by 2 Bristol BE.22 gas turbines and 1 DH Spectre rocket motor. AUW 15,300 lb. Span 28 ft. Length 44 ft. Height l2ft 3 in. The second version was powered by 1 Bristol BE.22 and 1 DH Spectre. AUW 8,800 lb. Span 20 ft. Length 34 ft 4 in. Height 11 ft.

P.162 1952-56
Schemes developed for a long-range reconnaissance and anti-submarine flying boat including also a transport version. Ref. P.104. Initially with twin fins and rudders and 4 Bristol Centaurus piston engines, consideration was then given to 4 Nomads, 4 BE.25 with 1 Avon RA.14 in the dorsal fin followed by 4 Centaurus with 2 Avons in the inboard nacelles above the piston engines and similar schemes with Nomads. At first retracting wing-tip floats were used but subsequent schemes reverted to fixed floats anda single fin and rudder. AUW varied from 135,000 - 155,000 lb. Wing span from 137 ft to 157 ft. Length 120 ft-126 ft 6 in. The ultimate version used 4 RB. 109 turbo-props with bomb-bays below the inboard nacelles. The wing had marked anhedral outboard of the outer nacelles, with retractable wing-tip floats, double slotted flaps and dive-brakes. Watertight doors were incorporated below the forward hull for a retractable ASV radar scanner and a door in the side of the hull at the rear was provided for lowering sonar equipment with the possibility of active sonar lowered through a further aperture with watertight doors behind the step, for a skimming mission with hydro-skis on the tip floats. AUW 148,000 lb. Span 136 ft. Length 114 ft 7 in. Gun armament was varied in type and position as the project evolved and included turret mounted 20 and 30 mm cannon. A crew of 14 was carried.

P.163 1953-54
Started as a project for a ‘Mach 2’ research aircraft with either 2 Olympus or 2 Avon RA.14 engines mounted on the tips of a short span, broad chord wing, it soon changed to a delta wing with 1 RA. 14 and 11500 lb thrust rocket motor in the fuselage. Through various changes to its configuration and the addition of Al radar and missile carriage, the design was tendered to MOS to Spec. ER.134.T. Further developed as P.177 the resulting aircraft became the SR. 177. A second crew member to operate the radar was considered at one stage.

P.164 1953
Schemes for the Princess with either 10 or 12 Napier Eland coupled turbo-props.

P.165 1953
Schemes for the Princess with either 6 P & W T.34 turbo-props, 4 AS/Wright TP.51A turbo-props based on Sapphire engines or 4 Allison T.40 and 2 Allison T.38 turbo-props.

P.166 1953
A 400,000 lb AUW flying boat with 400 seats and clam-shell doors for alternative cargo use. Span 277 ft. Length 183 ft. Height 58 ft with 4 Wright Turbo-Sapphires. An alternative version with 6 Allison T.40 turbo-props had the span reduced to 241 ft.

P.167 1953-54
Further development of P.154 leading to the definitive type SR.53. Schemes using AS Screamer rocket motor and AS Viper jet engine; DH Spectre and either Bristol BE.22 Saturn, DH.PS.31 or Bristol Orpheus jet engines.

P.168 1953
The Auster VI with Hydro-skis.

P.171 1952
A light transport with 2 AS Viper jet engines. AUW 9,000 lb. Span 52 ft. Length 38 ft 6 in. 10 - 14 seats.

P.173 1953-55
This covered a considerable amount of design effort to keep the Princess active. Schemes for alternative engine installation, 6 Bristol BE.25, 6 Bristol Proteus 705 or 755 and 6 Rolls Royce RB.109, together with a proposal to extend the forebody with a matching increase in the height of the fin and rudder; also a rearward extension of the planing bottom. Internal schemes for the accommodation of between 130 and 264 passengers and freight carriage were investigated. A military version as an early warning radar station and fighter carrier was proposed. This carried two SR.53 type fighters under the wings and was based on the version with the extended hull.

P.175 1953-54
The Australian GAF Jindivik and Pika piloted target aircraft modified by the fitment of hydro-skis and buoyancy chambers for water landing. Several retractable types of skis were investigated.

P.176 1953-55
A twin-engined medium range flying boat maritime patrol aircraft for New Zealand requirements. 2 Rolls-Royce RB.109 turbo-prop. engines. 117 ft wingspan. AUW 70,000 lb. A modified version for the RAF for North Atlantic operations at an AUW of 93,000 lb with wing span increased to 124 ft included 4 Rolls-Royce Soar turbo-jet engines in addition for use at take-off. This project had started with 4 Bristol Hercules piston engines followed by a variety of power plants which included 4 Centaurus, 4 RB.109s, 4 Darts, 4 Elands or Mambas before the final configuration was reached. AUW varied from 70,000 to 110,000 lb with wing spans of 107 to 130 ft.

P.177 1954-58
Became the SR.177.

P.178 1954
Two versions of a twin-jet swept-wing naval strike aircraft with crew of two side-by-side. 2 DH Gyron Junior PS 37 engines mounted above the rear fuselage or alternatively above and forward of the wing at one-third span. Wing span 95 ft. AUW 50,000 lb.

P.179 1954
Single-seat strike fighter with Bristol Orpheus or 8,000/10,000 lb thrust DH.PS.37 jet engine. Delta wing of 26 ft 6 in span. AUW 12,500/15,700 lb. A version with hydro-skis was also projected.

P.180 1954
Single-seat supersonic interceptor with one DH.PS.37 8,000/10,000 lb thrust jet engine. Delta wing of 26 ft span. AUW 15,300 lb.

P.186 1955
Adaptation of P.163 for an Australian requirement.

P.187 1955-56
Mach 2 all-weather fighter to Spec. MOS F. 1 55T. After three schemes based on a straight tapered wing, the design evolved into a delta wing type with 2 DH PS.52 jet and 4 DH Spectre rocket engines carrying 2 Red Dean and 4 Blue Jay missiles with a crew of two. Span 48 ft. AUW 107,500 lb. The nose cone could be raised for max. performance and lowered for forward vision.

P.188 1955
VTO schemes to Spec. ER. 156.T with 16 or 18 Rolls-Royce RB.121s mounted in line in the wing or stacked at the wing-tips or 4 RB. 122 engines mounted two at the wing-tips and two on the fuselage. AUW 180,000 lb - 210,000 lb. Length 181 - 195 ft. A version with a delta wing and end plate fins with 18 RB 121s was also schemed.

P.189 1955
Further investigation of the hydro-ski applications to fighters and to an Auster AOP.9. (Ref. P.168).

P.190 1955
Investigation of a 4% steel wing. The Bristol 188 resulted from the official requirement.

P.192 1956
A long-range passenger/cargo flying boat of 1,500,000 lb weight and 313 ft wing span, fitted with 24 Rolls-Royce Conway by-pass turbo-jet engines. The aircraft could accommodate up to 1,000 passengers on four decks in similar accommodation to a luxury liner. A version with T tail and 16 Bristol BE.25 turbo-props was also prepared.

P.193 1956
Known as a Combat Information Centre, this was an AEW version of the Princess with extremely long range. Also suitable for adaptation as a flight refuelling tanker or troop transport. 6 - 8 Bristol BE.25 turbo-props.

P.194 1956
Floats and chassis for Scottish Aviation Twin Pioneer.

P.195 1956-57
Four versions of a turbo-jet VIP transport for 7 passengers including crew. 2 x 2,400 lb ST Rolls-Royce RB.108, later 2 x 2,000 lb ST Armstrong-Siddeley Vipers. Engines were positioned in pods below the wings on the high wing version and on the sides of the rear fuselage and the tips of the tailplane on a low-wing version. The fourth version had engines buried in the fuselage and these could be tilted to assist take-off.

P.196 1957
A missile target. Four unmanned and one manned version based on the SR.53. Early schemes employed various power plants. Both manned and unmanned versions used 2 AS Vipers on the wing-tips with an AS 9/3 rocket motor in the rear fuselage. One target version used 1 Bristol Orpheus 1 DH Spectre and 4 Bristol 18 inch Ramjets positioned on the wing tips and rear fuselage.

P.199 1957
Landplane freighter version of the SR.45 Princess with six nacelle-mounted Rolls-Royce Tyne engines. Schemes for conversion from the existing Princess flying boats at Cowes including means for floating them to a suitable airfield were prepared in some detail.

P.200 1957
Schemes for a 30 ft long hydrofoil assault vessel to be carried and guided by a mother-ship. The craft was driven by a single turbo-prop and was based on a channel section hull with missiles carried in the cavity.

P.201 1957
Various versions of an executive aircraft for 10 passengers plus crew based on the SR.177. Schemes with two AS Viper or Bristol Orpheus engines.

P.202 1957
A Mach 1.8 executive aircraft for 8 rearward facing passengers plus 3 crew. 3 tail-mounted Bristol Orpheus BOR 12 engines. AUW 50,000 lb. Length 71 ft. Span 36 ft. Based on SR.177.

P.203 1958
Investigation of the use of 4 Rolls-Royce Tyne and 2 Pratt & Whitney T.57 engines in the SR.45 Princess.

P.204 1958
Light agricultural monoplane - six schemes including schemes for carrying a second and third man.

P.205 1958
Skeeter development including 3 seater and Continental engine.

P.206 1958
Various schemes for panto-based and floatplane versions of the HDM 106 (Hurel-Dubois Miles).

P.207 1958
The HDM. 106 which was used as a basis for a light twin-engined transport similar to the Short Skyvan.

P.208 1958
A twin-engined flying boat Maritime Patrol aircraft to NATO requirements built round advanced submarine detection equipment. 2 Rolls-Royce Tyne 11 turbo-prop. engines. 150 ft wing span. AUW 73,000 lb. A retractable hydro-ski was embodied in the hull. A 65 passenger civil version was considered.

P.209 1958
Various schemes to develop the SR.53 with twin DH Spectre and Rolls-Royce Soar engines including the carriage to altitude on a Valiant bomber.

P.210 1958-65
Hovercraft. Various types including SR.N1 and SR.N2.

P.211 1958
Anti-submarine project. Initially schemed as a STOL four-engined float seaplane, finally developing into a V/STOL four engined amphibious flying boat with tilt-wing. 120 ft span, 100,000 lb AUW. 4 Rolls-Royce Tyne turbo-props of 5500 HP. An intermediate scheme known as a Hover-Air-Craft incorporated hovercraft technology in the hull of a flying boat of 120,000 lb AUW with a tapered wing of 162 ft span which could fold upwards at the approach to the landing. Power was supplied by 1 Rolls-Royce Tyne engine and either 2 Rolls-Royce Avon RA.29 or Conway RCo. 11. The central pod-mounted engine was used for propulsion only. The outer engines operated in ducts and provided power for both lift and propulsion. Alternative versions with cranked delta wings of 120 ft span with foldable outer sections were also schemed.

Submarine cargo vessel. Length 604 ft. Max. diameter 72 ft. Displacement - submerged - 50,000 tons. Dead weight 28,000 tons.

P.213 1958-59
Studies of nuclear-powered flying boats. Two versions of a 1,000,000 lb, 310 ft span machine powered by 2 indirect-cycle reactors driving 6 power turbines with or without 4 intermediate compressor turbine sets. Two similar versions of a 600,000 lb, 250 ft span machine plus an alternative twin hull version. Schemes included proposals by GEC for a direct-cycle reactor in conjunction with T.57 engines.

P.214 1959
Scheme to fit Rolls-Royce Tyne engines in the Martin Marlin P5M-2 flying boat.

Meter rating tank.

Towed flexible tank (Flecon).

Submersible hydrofoil craft (in conjunction with Miles).

Hydrofoil landing craft. Alternatives with airscrews or marine propulsion.

P.219 1959
Helicopter-assisted airship - Skeeter or P.531.

P.220 1959
Autogyro studies.
An 8,000 lb single rotor machine. Twin engines on a high stub wing. A similar machine but with twin rotors mounted on the tips of an extended wing. Several versions of an autogyro based on the P.531 helicopter with single and twin propellers also shortened tail versions of both types. An entirely new design with 475 HP Artouste seating pilot and 4 passengers using the P.531 rotor. Conventional tractor propeller and a 30 ft span tapered cantilevered low wing.

P.221 1959
Hover-fly jeep 8,000 lb AUW.

P.222 1959-60
Various helicopter studies based on the Westminster and Wasp including a 5 seat Autogyro."


Senior Member
Jun 25, 2009
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Thanks a lot, Robunos! I reworked your post to make it a little more readable. That was quite a task but worth it in the light of all the great information contained therein.


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Jun 25, 2009
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That "SR.56" is most likely a mistake and that's why I chose not to include it in my various posts. The Flight article is dated 1946. If one follows the chronology, the Saunders-Roe list had indeed just switched from S. to SR. but, the latest design at the time was the SR.45 Princess, which was already pictured all over the place at the time although it didn't fly until 1952. By comparison, the SR.53 didn't appear until much later, flying in 1957. If an "SR.56" ever existed, it must be a design posterior to the SR.53, which is obviously NOT the case in that 1946 article!!


You're Mad, You Are.....
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May 1, 2007
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I reworked your post to make it a little more readable....
No probs, Star. The original was in two column format, hence the compressed
I generated it using OCR, which I've just found out how to do without expensive,
special, software. :D
There's also lists of rotorcraft projects, and pre-war projects, to come shortly.....



You're Mad, You Are.....
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May 1, 2007
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Helicopter projects at Eastleigh (from same source as postwar projects, above)

P.500 1951
Medium size pod and boom type helicopter with twin piston engines mounted on a low wing. Tip driven three blade rotor propelled by pulse-jets. Twin fins and rudders.

P.502 1951-59
Development of the basic Skeeter to final Mk.12 form, including trial installations of the rocket-boost installation and casualty evacuation equipment.

P.507 1953
Light two-seat reconnaissance helicopter to MOA Specification HR.144T. Two blade rotor tip-driven by 2 Saunders- ,Roe 8’/2 inch pulse-jets. 360° vision. AUW 1500 lb.

P.508-1 1953
Light pod and boom type helicopter with tail rotor. Twin gas turbines on high stub-wings driving three-blade main rotor.

P.514 1953
‘Rotorcoach’. Large twin-engined twin- rotor passenger helicopter with centrally mounted low wing for 50 passengers. Design study to MOS Specification 7/Policy/242/RD(H).

P.519, P.521, P.529, P.530 1954-57
Various schemes leading to the P.531.

P.531 1957
The project which reached production as the Westland Scout and Wasp.

P.534 1960
The Skeeter with skid undercarriage.

P.537 1959-60
The Turmo powered Skeeter XM.563.

P.538-2 1964
Light two seat reconnaissance helicopter to replace the Skeeter with 350 shp Turbomeca Astazou (de-rated from 550 shp). AUW 2600 lb.

P.539 1967
Vectored slipstream VTOL/STOL type aircraft. Two 1500 shp DH Gnome gas turbines mounted on a high wing with limited tilt and large double nesting flaps.

P.540-1 1960
Ground reconnaissance vehicle with airborne capability based on the Champ road vehicle powered by a Coventry Climax engine. A 980 shp Blackburn Nimbus gas turbine drove a four blade main rotor and a tail rotor on a foldable rear extension for airborne use.

P.540-2 1960
Ground reconnaissance vehicle with obstacle jump and swimming capability using the ground running gear of the Champ vehicle. Maximum jump to 17 ft high over 75 ft at AUW of 6750 lb was obtained by means of a contra-rotating ducted fan with four blades of 7 ft 6 in diameter ballasted for energy storage. Power for all operations was provided by a 300 hp Lycoming six cylinder horizontally opposed air-cooled engine restricted to 90 hp for ground use.

P.541-1 1960
A five-seat passenger helicopter powered by two 800 shp Blackburn Turmo 603 gas turbines. Conventional configuration with transmission and four-blade main rotor and tail rotor making use of P.531 components. Twin Turbomeca Astazou engines also under consideration.



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Pre-War and Wartime Projects (from same source as postwar projects, above)

Patent No. 296570 1927
Twin-hulled flying boat.

Patent No. 262579 1926
A high-speed seaplane with twin floats retracting inwards to form a single float.

Patent No. 296594 1927
A high-speed seaplane with central float and hinged wing-tip and floats. A version of alternative construction and with fixed wing-tip floats was also specified.

No Type No. 1926
A braced low wing monoplane with 750 HP Napier Lion engine designed by S.E. Saunders and F.P.H. Beadle for the 1926 Schneider Trophy Contest. Span 26 ft 5 in. Length 25 ft 6 in. Height 9 ft 9 in. Wing section RAF 33. Wing area 98 sq. ft. Wing loading 25.33 lb per sq. ft. Maximum take-off weight 2,502’/2 lb: fuel 437’/2 lb (621/2 gallons), oil 75 lb (7’/2 gallons), coolant 85 lb (8’/2 gallons). Power loading 3.33 lb per HP. Patents Nos. 262579 of 1926 and 296594 of 1927 were taken out for retracting floats, neither version of which was employed in this design. Performance: max. speed at sea level 285 mph, landing speed 881/2 mph.

P.228 1929
The Severn as a civil aircraft for 21 passengers and three crew.

P.295 1930
Military training version of Cutty Sark with forward and mid-ships gun rings.

P.296 1930
Coastal patrol version of Windhover with forward and mid-ships gun rings.

P.351 1930
Severn Mk.III powered by 2 Rolls-Royce Buzzard Mk.II engines.

P.393 1931
Cloud Mk.II, a three engined biplane version.

P.395 1931
Became the Spartan Cruiser.

P.398 1931
Became the single-engined Cutty Sark.

P.399 1931
Spartan light cabin monoplane with Napier E.97 Javelin engine.

P.463 1932
Became the RAF Cloud.
P.476 1933

Small military flying boat with folding wings for shipboard use. 1 Napier Rapier with tractor airscrew and gun ring amidships.

P.507 1931
Became the London.

P.555 1934
Military version of the Cloud with 2 Napier Rapier engines. Gun rings at forward and mid-ships positions.

Windhover II passenger amphibian. 2 Gipsy VI engines. Strut-braced high wing with undercarriage housed in balancing floats.

P.713 1938
A strut-braced high-wing monoplane with sponsons. Based on the London Mk.II.

P.714 1938
An alternative to P.713 with balancing floats.

P.792 1936
The final scheme for Spec. R2/33 which became the A.33.

P.937 1939
Identified as Cloud Mk.II but unrelated to the earlier machine. Twin-engined military amphibian with strut-braced high wing and balancing floats.

P.970 1936
Flying boat to Specification R1/36. Became the Lerwick.

P.1029 1939
Projected A.37 a scaled down R5/39. Revised to P.1063 by September 1942 for Shetland trials.

P.1031 1940
See below S.39.

P.1033 1940
A four-engined tank-carrying monoplane.

P.1034 1940
See below. S.39A.

P.1036 1939-41
A single-engined flying boat amphibian monoplane (9,500 lb) identified as Scheme A and powered by a Bristol Mercury XVI. The engine pod extended aft to house a gun turret and to carry the tail

P.1037 1939-40
A more conventional central float version of P.1036 identified as Scheme B.

P.1039 1940-41
A single-engined monoplane central float type amphibian powered by a Rolls-Royce Merlin for use for the Fleet Air Arm. Spec.S 12/40. AUW 12,000 lb. Span 50 ft. Length 49 ft 9 in. Crew of 5; the observer was housed in the trunk. The rear section of the fuselage, complete with the tail surfaces, folded forward for stowage purposes.

P.1050 1940-41
A single-engined biplane flying boat amphibian with the engine pod extended aft to house a gun turret and to carry the tail surfaces. Spec.S12/40. AUW 12,000 lb.

S.36/C 1939
Mailplane and civil transport versions of the Lerwick. Proposals to Imperial Airways.

S.38 1938-39
Schemes for a large reconnaissance flying boat initially to Spec.R3/38 (53,000 lb AUW) with 4 Bristol Taurus engines later becoming R5/39 (55,000 lb AUW) in May 1939.
Later 110 ft span, 70,000 lb AUW. 4 Bristol Hercules engines or Rolls-Royce Griffons and with inward retracting stabilising floats. (The A.37 was a scaled down version of the proposed R5/39).

S.38A 1939-40
The company proceeded on a private venture basis after the specification was terminated in October 1939. By April 1940 Centaurus engines had replaced the Hercules and the armament raised to 20 mm cannon in a Boulton Paul turret. 80,000 lb AUW.

S.39 (P.1031) 1940
Further development of the schemes for (P.1031) large military flying boats to meet Spec.R5/39 and R14/40 from August. Various locations of armament. 4 Bristol Centaurus engines. Span 137 ft. AUW progressively increased 70,000 - 96,000 lb. Bare weight 44,300 lb. Napier Sabre engines as alternative power units.

S.39A (P.1034) 1940
A scheme for a flying boat with retractable bottom.

S.40 1940
The continued development of the large (Oct-Dec)flying boat to a civil version of current military R14/40 schemes. 31 passengers and 1500 cubic ft of cargo. AUW 82,000 - 112,000 lb.
Span 140 ft.

S.41 1941
The large military flying boat finally (Jan) evolved to meet Spec. R. 14/40 for which the Short Shetland was selected. 110,000 lb AUW 3800 miles range. 4 Bristol Centaurus. 3 four gun turrets plus a four cannon tail turret.

S.42 (P.1057) 1942-43 Military flying boat. 4 Rolls-Royce Merlin XX engines using wing of Avro Lancaster. 70,000 lb AUW. 2500 - 3000 miles range.

S.42A (P.1059) 1942-43Freight carrying version with 4 Rolls-Royce Merlins or 4 Bristol Hercules VI engines. 35,800 lb cargo.

No Type No.1944
Long range transport flying boat with 6 Bristol Centaurus engines.

NoType No.1944
Long range transport flying boat with 8 Bristol Centaurus engines.



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hesham said:
and also there;

SR.50,SR.51 and SR.52,as I know they were a research aircraft.


it is the first time in my life to know that,the SR.177 was also called SR.55.

Source Air Pictorial Nov 1958.


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ACCESS: Above Top Secret
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Not mentioned in Tagg/Wheeler "From Sea to Air" either. Nevertheless, maybe interesting, it is mentioned,
that after withdrawal of the Germans and the British services, SR tried to keep this project alive by proposing
variants of the SR.177 to be build for research purposes with different wing planforms, such as W and reversed
W planforms. No designations given unfortunately, but this could have been an interesting bird !


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When you take a look at the number of derivative projects that Saunders-Roe elaborated from the Princess, the SR.A1 or the SR.177 (as wonderfully listed by robunos in previous page) you can only be astonished at how long they tried to keep the designs alive in the hope of reviving some official interest that never came...

One story that definitely need to be told is that of the NP Princess (nuclear-powered SR.45). This project kept both Saunders-Roe and Convair very busy during 1956-1958, for the U.S. Navy and presumably also for the Royal Navy. The Spangenberg collection states that several boxes of documents pertaining to the project are extent. I hope some historian can access these and write a book about it. That would be something, wouldn't it?


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Incredible design my dear Jemiba,

thank you for sharing us.


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May 26, 2006
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and also there;

SR.50,SR.51 and SR.52,as I know they were a research aircraft.

Maybe the source for that Info is Jane's Encyclopedia of Aviation,Edition 1989,
but I could be wrong,and actually I read it from more than 30 years,and I didn't
buy this book,so very possible it was a misprint or something else,but to check
if anyone had it,he can eliminate us ?.

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