General Aircraft from ST.1 to GAL.65 — THE DEFINITIVE INDEX

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The Mono-Spar Co., Ltd., was formed in London in 1929 by Swiss-born inventor Helmut J. Steiger to design and build aircraft wings according to a new technique he had developed. Then on 27 February 1931 he formed The General Aircraft Co., Ltd., the purpose of which was to undertake production of aircraft using his 'Monospar' wing design.

All the aircraft that were produced under Stieger's helm were developed by his Mono-spar company but built by his General Aircraft company. All carried the name commercial "Monospar" and used "ST." designations to denote Stieger designs. For instance, design ST.4 was casually refered to as the "Monospar ST.4", or design ST.25 as the "Monospar ST.25 Universal", without it actually referring to a company name, as has often been thought. They were actually the General Aircraft ST.4 "Monospar" and General Aircraft ST.25 "Monospar Universal", which is evidenced notably by (1) period advertisements, (2) the absence of a hyphen in the word "Monospar" (indicating the commercial name and not the designing company's name) and also (3) civil register entries.

In the following pages, some decisions were made for clarity purposes: the early Stieger designations used Roman numerals (ST.I, ST.II etc.) have been replaced by Arabic numerals (ST.1, ST.2, etc.) as was customary in period publications, anyway; the "G.A.L." designations have been simplified as "GAL.", both for readability purposes and also better indexation in search engines; and measure units were simplified in specification figures ("lb" instead of "lbs.", "mph" instead of "m.p.h.", etc.).


ST.1
Type: Monospar wing
Built: 1929
Built by: The Mono-Spar Co., Ltd., London

The ST.1 was a new type of cantilever wing developed by Swiss-born H. J. Stieger. It was ordered for testing by the British Air Ministry.
 

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ST.2

Type: Monospar wing
Constructed: 1931
Fitted to aircraft by: The Gloster Aircraft Co. Ltd., Brockworth
First flown
: Autumn 1931

The ST.2 was a Monospar wing ordered by the Brtish Air Ministry that to be fitted experimentally to a Fokker F.VIIB/3m trimotor [J7986]. The two engines were Armstrong Siddeley Lynx types.



Besides the items attached below, some very informative period articles can be found in the following issues of Flight:

http://www.flightglobal.com/pdfarchive/view/1931/1931%20-%200739.html
http://www.flightglobal.com/pdfarchive/view/1931/1931%20-%200740.html
http://www.flightglobal.com/pdfarchive/view/1931/1931%20-%200741.html
http://www.flightglobal.com/pdfarchive/view/1931/1931%20-%200742.html
http://www.flightglobal.com/pdfarchive/view/1931/1931%20-%201312.html
 

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ST.3 "Monospar"

Type: Twin-engine three-seat enclosed cabin monoplane prototype
Powerplants: two 45 hp Salmson A.D.9 engines
Manufactured by: The Gloster Aircraft Co., Hucclecote, Gloucester*
First flight: Spring 1931

The ST.3 was developed to apply Stieger's Monospar cantilever wing construction to a general aviation type. Monospar features were also applied to fuselage construction.

*NOTE: The aircraft was also known as the Gloster SS.1 (Stieger Salmson 1).


Number built: 1 [G-AARP]


Specifications
Span: 38 ft.
Length: 21 ft. 11½ in.
Height: 9 ft.
Wing area: 183 sq. ft.
Empty weight: 1057 lbs.
Loaded weight: 1800 lbs.

Performance
Maximum speed: 110 mph
Cruising speed: 95 mph
Climb rate: 950 ft./min
Service ceiling: 18,000 ft.



Besides the items attached below, some very informative period articles can be found in the following issues of Flight:

http://www.flightglobal.com/pdfarchive/view/1931/1931%20-%200713.html
http://www.flightglobal.com/pdfarchive/view/1931/1931%20-%200714.html
http://www.flightglobal.com/pdfarchive/view/1931/1931%20-%200715.html
http://www.flightglobal.com/pdfarchive/view/1931/1931%20-%200716.html
http://www.flightglobal.com/pdfarchive/view/1931/1931%20-%201083.html
http://www.flightglobal.com/pdfarchive/view/1931/1931%20-%201084.html
http://www.flightglobal.com/pdfarchive/view/1931/1931%20-%201177.html
 

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ST.4 "Monospar"

Type
: light twin-engine four-seat cabin monoplane
Powerplants: two 85 hp Pobjoy R radial engines
Manufactured by: General Aircraft Ltd., Croydon, Surrey
First flight: May 1932

The ST.4 was the production model of the ST.3 prototype, meant for light transport, feeder line and private owners. The fuselage was of a tubular framework forward with a single girder to the tail and fabric covering over light secondary structure. The wings were monospar with triangular bracing and former ribs of duralumin, and were fabric covered. The tail unit was built likewise. The 1933 Mark II version featured various modifications and refinements such as a nose landing light. Some examples were later refitted with Niagara engines.


Number built:
  • 1 prototype [G-ABUZ]
  • 5 Mk. I production aircraft [G-ABVN, G-ABVO=VT-ADT, G-ABVP=X9434, G-ABVR=CH347, G-ABVS]
  • 24 Mk. II production aircraft [included G-ACCO=X9376=DR849, G-ACCP, G-ACEW, G-ACFR, G-ACHS, G-ACGM, G-ACHU, G-ACJE=MM245=I-AGAR, G-ACJF, G-ACKT, G-ADBY=ZS-AHE=SAAF1507=IS113, G-ADIK, G-ADJP=X9367*, G-ADLM]
    * another source gives X9367


Specifications:
Length: 26 ft 4 in
Height: 7 ft
Wing span: 40 ft 2 in
Wing span (folded): 14 ft 10 in
Wing area: 219 sq ft
Fuel capacity: 40 gallons
Oil capacity: 4 gallons
Empty weight: 1480 lb
Loaded weight: 2550 lb (Pilot + 3 passengers: 640 lb; luggage: 100 lb; fuel + oil: 330 lb)

Performance:
Maximum speed: 130 mph
Cruising speed: 115 mph
Landing speed: 48 mph
Climb rate: 850 ft/min
Service ceiling: 15000 ft
Absolute ceiling: 18000 ft
Range cruising: 540 miles
Duration: 4 hr 30 min



Besides the items attached below, some very informative period articles can be found in the following issues of Flight:

http://www.flightglobal.com/pdfarchive/view/1932/1932%20-%200365.html
http://www.flightglobal.com/pdfarchive/view/1932/1932%20-%200366.html
http://www.flightglobal.com/pdfarchive/view/1932/1932%20-%200367.html
http://www.flightglobal.com/pdfarchive/view/1932/1932%20-%200368.html
http://www.flightglobal.com/pdfarchive/view/1932/1932%20-%200369.html
http://www.flightglobal.com/pdfarchive/view/1932/1932%20-%200370.html
http://www.flightglobal.com/pdfarchive/view/1932/1932%20-%200371.html
http://www.flightglobal.com/pdfarchive/view/1932/1932%20-%200372.html
http://www.flightglobal.com/pdfarchive/view/1932/1932%20-%200565.html
http://www.flightglobal.com/pdfarchive/view/1932/1932%20-%200615.html
http://www.flightglobal.com/pdfarchive/view/1932/1932%20-%201058.html
http://www.flightglobal.com/pdfarchive/view/1932/1932%20-%201059.html
http://www.flightglobal.com/pdfarchive/view/1932/1932%20-%201143.html
http://www.flightglobal.com/pdfarchive/view/1932/1932%20-%201144.html
 

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ST.5

Type: Monospar wings
Date: 1932

The ST.5 designation applied to wings similar to those of the ST.4 and built under subcontract to Spartan for their Clipper monoplane. The Clipper participated in races but remained a lone prototype.
 

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ST.6 "Monospar"

Type
: light twin-engine 4-/5-seat cabin monoplane
Powerplants: two 85 hp Pobjoy R; 90 hp Pobjoy Niagara I also used
Date: 1933

The ST.6 was similar to the ST.4 Mk. II but featured a manually retractable undercarriage and could accomodate a fifth passenger. It was flown in the King's Cup race in 1933 and 1934.



Number built:
  • 2* ST.4 conversions [G-ACHU and one more*]
  • 2 aircraft built [G-ACGI=AV979, G-ACIC]
Earlier sources stated that only three ST.6 aircraft had existed.



Specifications
Dimensions same as ST.4
Empty weight: 1530 lb
Loaded weight: 2550 lb
Disposable weight: 1020 lb
Fuel & Oil: 340 lb

Performance
Maximum speed: 138 mph
Cruising speed: 124 mph
Stalling speed: 53 mph
Landing speed: 48 mph
Landing run: 330 ft.
Take-off run: 360 ft.
Climb rate: 850 ft/min
Absolute ceiling: 17500 ft
Cruising range: 560 miles (800 miles with additional tankage range)
 

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ST.7

Type: Monospar wing
Date: 1934

The ST.7 was a Monospar wing built by Saunders-Roe the General Aircraft's patent for testing on the third A.19 Cloud [K2681]. This received the new designation A29 Monospar Cloud and was powered by two Armstrong-Siddeley Serval engines.
 

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ST.8

Type: Monospar wing
Date: 1933

The ST.8 was a Monospar wing delivered in 1933 to the Italian Air Ministry and test-flown on a Caproni Ca.97 "colonial" transport.

NOTE: I haven't been able to find any image of that Ca.97. However, there was an experimental Caproni type, the Ca.127, which was built with a Monospar wing and can be seen on the Italian Wikipedia.
 
ST.9

Type: Monospar wing
Date: circa 1933-34

The ST.9 was a Monospar wing ordered for an Italian sailplane. Although it was designed, it eventually was not built, for unknown reasons.
 
ST.10 "Monospar"

Type: light twin-engine four-seat cabin monoplane
Manufactured by: General Aircraft Co., Ltd., Feltham, Middlesex
Powerplants: two 90 hp Pobjoy Niagara I engines
Date: 1934

The ST.10 was siimilar to the ST.4 with fixed undercarriage, dual controls, the fuel tank located behind the cabin floor and various improvements. The first of two aircraft, initially known as the T.V, became the winner of the 1934 King's Cup Race, with Flight Lieutenant Schofield at the controls and J. J. Stieger himself as the passenger. The type served with Portsmouth, Southsea and Isle of Wight Aviation from late 1937 onwards.


Number built: 2 [G-ACTS=X9453 and VH-UST]


Specifications
Length: 26 ft 4 in
Height: 7 ft 10 in
Wing span: 40 ft 2 in
Wing area: 217 sq ft
Empty weight: 1470 lb
Loaded weight: 2550 lb

Performance
Maximum speed: 144 mph
Cruising speed: 132 mph
Climb rate: 900 ft/min
Service ceiling: 16000 ft
Absolute ceiling: 18000 ft
Take-off run: 235 ft
Range at cruising speed: 594 miles
Duration: 4 hr 30 min
 

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ST.11 "Monospar"

Type:
Powerplants: two 90 hp Pobjoy Niagara engines
Date: 1934

The ST.11 was a retractable undercarriage version of the ST-10, just like the ST.6 was a retractable undercarriage variant of the ST.4. The two aircraft built were said to be delivered to the Australian government, but soon fell into the hands of local private owners.


Number built: 2 [VH-UAZ, VH-USN]


Specifications
Dimensions same as the S.T.10
Empty weight: 1524 lb
Loaded weight: 2500 lb

Performance
Maximum speed: 160 mph
Cruising speed: 150 mph
Climb rate: 970 ft/min
Take-off run: 336 ft.
Service ceiling: 17400 ft
Absolute ceiling: 19400 ft
Range at cruising speed: 675 miles
Duration: 4 hr 30 min
 

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ST.12 "Monospar"

Type: light twin-engine four-seat cabin monoplane
Powerplants: two 130 hp de Havilland Gipsy Major engines*
Date: 1935

The ST.12 light transport and touring aircraft was similar to the ST.11 but different engines.

*One aircraft [G-ADLL] was fitted with two 145 hp Gipsy Major high compression engines. The performance figures below only apply to the regular version.


Number built:
  • 1 prototype [G-ADBN=HB-AIR=BD150]
  • 9 production aircraft [VH-UTH, VH-UTK, G-ADDY, G-ADDZ=ES-AXY, VH-UTM, VH-UTZ, G-ADLL and one more]


Specifications
Length: 26 ft 4 in
Height: 7 ft 10 in
Wing span: 40 ft 2 in
Wing area: 217 sq ft
Empty weight: 1840 lb
Loaded weight: 2875 lb

Performance
Maximum speed: 158 mph
Cruising speed: 140 mph
Climb rate: 1233 ft/min
Service ceiling: 21000 ft
Range: 410 miles
 

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ST.13, ST.14, ST.15, ST.16, ST.17


These five designations are said to have been applied to projects but none of them have been identified.


It is known that the last Avro Ten built was fitted with a Monospar wing circa 1936.
 
ST.18 "Croydon"

Type: twin-engine ten-seat monoplane transport
Powerplants: two 450 hp P&W Wasp Junior SB-9 engines
Manufactured by: General Aircraft Co., Ltd., Hanworth, Middlesex
Date: 1935

The ST.18 was a light transport derived from the Monospar cabin series with accomodation for one pilot and nine passengers. The sole prototype left for Australia in 1936 but was lost in October on the return journey from a tragic compass error. No other ST.18 was built.


Number built: 1 [T.22=G-AECB]


Specifications
Length: 43 ft 3 in
Wing span: 59 ft 6 in
Empty weight: 7974 lb
Loaded weight: 11500 lb

Performance
Maximum speed: 203 mph
Cruising speed: 190 mph
 

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ST.19, ST.20, ST.21, ST.22, ST.23, ST.24


These six designations were skipped to provide the new Monospar variant with the number "25" in honor of King George V's 1935 Silver Jubilee.
 
ST.25 "Monospar Jubilee"

Type: light twin-engine five-seat cabin monoplane
Powerplants: two 90 hp Pobjoy Niagara engines
Date: 1935

The Jubilee was a four- to five-seat utility aircraft that was basically an improved version of the ST.4. Its designation "S.T.25" was specially assigned to honor King George V's Silver Jubilee (25 years of reign). Although lacking the refinements of later ST.25 models, the Jubilee was by far the best in terms of performance.


Number built:
  • 1 prototype [G-ADIV]
  • 29 production aircraft.


Specifications
Length: 26 ft 4 in
Height: 7 ft 10 in
Wing span: 40 ft 2 in
Wing area: 217 sq ft
Empty weight: 1680 lb
Loaded weight: 2875 lb

Performance
Maximum speed: 142 mph
Cruising speed: 130 mph
Climb rate: 800 ft/min
Service ceiling: 16000 ft
Range: 585 miles
 

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ST.25 "Monospar Jubilee Freighter"

Type: light twin-engine transport monoplane
Powerplants: two 90 hp Pobjoy Niagara II engines
Date: 1935

As its name implies, this was a freighter version of the Jubilee.


Number built: 4 [registrations unknown]


Specifications and performance
Same as the Jubilee
 
ST.25 "Monospar Ambulance"

Type: light twin-engine transport monoplane
Powerplants: two 90 hp Pobjoy Niagara II engines
Date: 1936

This was originally an air ambulance version of the Jubilee accomodating stretcher and attendants. However, the later examples were fashioned after the Universal version with twin tails and Niagara III engines.


Number built: 6 [G-AEVN, G-AEWN, G-AEGX, G-AEYF=OY-DAZ and two more]


Specifications and performance
Same as the Jubilee
 

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ST.25 "Monospar De Luxe"

Type: light twin-engine cabin monoplane
Powerplants: two 95 hp Pobjoy Niagara III engines
Date: 1936

This was a refined version of the Jubilee with upgraded engines and twin fins/rudders which improved the directional control of the aircraft on one engine.


Number built: the De Luxe version does not appear as such in the civil register [G-AEDY, G-AEGY known to have been De Luxe]


Specifications
As the Jubilee except empty weight: 1758 lb

Performance
Maximum speed: 135 mph
Cruising speed: 123 mph
Climb rate: 700 ft/min
Service ceiling: 12000 mph
Range: 495 mph
 

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ST.25 "Monospar Universal"

Type: light twin-engine cabin monoplane
Powerplants: two 95 hp Pobjoy Niagara III engines
Date: 1935

The Universal was the second main production version of the ST.25. It featured the twin-fin arrangement and engine upgrade of the De Luxe.

Number built: 40 (the number includes the De Luxe version as the two can't be told apart in the civil register)

Specifications
Same as the Jubilee except
Length: 25 ft 4 in
Empty weight: 1818 lb

Performance
Maximum speed: 131 mph
Cruising speed: 115 mph
Climb rate: 710 mph
Service ceiling: 15300 ft
Range: 420 miles
 

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ST.25 "Monospar Universal" (tricycle)

One special Universal was built for the purpose of conducting tricycle landing gear tests. It was initially flown with "B Condition" registration T42 but was delivered to the Royal Aircraft Establishment in May 1938 as N1531.


Number built: 1 prototype [T42=N1531]
 

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GAL.26

Type: light twin-engine 4/5-seat transport aircraft
Powerplants: two 90 hp Cirrus Minor I engines
Date: 1936

The GAL.26 was a one-off aircraft, an ST.25 with different engines and trousered main undercarriage. It is said that it was converted from an ST.25 but what airframe was used for the modifications is not known.
NOTE: this was the first aircraft to carry the "GAL" prefix instead of "ST" as founder H. J. Steiger had just left the company.

According to member Ursrius:
Ah, that old red herring!
I have only seen two photographs that purport to be it, one in Aeroplane Spotter for June 26, 1948 and the other in Air Enthusiast May/June 2001.
However, comparison with photos in Aeroplane for 2-Jan-1935 show that the Aeroplane Spotter photo was most certainly that of the prototype ST-12. The Air Enthusiast photo (the one you show) would also appear to be from the same time and the hanger behind seems almost certainly to be GAL's at Croydon, the GAL.26 being built at Hanworth.
The GAL.26 was the ST-25 Jubilee G-ADWI modified with Cirrus Minor engines in 1936. The only photograph I have seen that I believe to be the GAL.26 was in a Cirrus Aero Engines advert in Flight, November 19.
http://www.flightglobal.com/pdfarchive/view/1936/1936%20-%203161.html


Number built: 1 conversion [G-ADWI]


Specifications
No data

Performance
No data
 

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GAL.27

Type: twin-engined transport
Powerplants: two 225 hp Menasco B6-S or two 205 hp de Havilland Gipsy engines
Date: 1936
Number built: none

This was a twin-engined transport project studied in four variants: high- or mid-wing, and with a choice of two different engine types for each.
 
GAL.28

Type: high-speed single-seat fighter
Powerplants: one Bristol Hercules engine
Date: 1936
Number built: none

This high-speed single-seat fighter project was designed to Spec. F.35/35 and featured a wing of variable area.
 
GAL.29

Type: high-wing 12-seat transport aircraft
Date: 1937
Number built: none

Three variants of this project were developed, each with a different engine type:

GAL.29A — to be powered by four 375 hp Armstrong Siddeley Cheetah X engines.
GAL.29B — to be powered by four 225 hp Menasco B6-S engines.
GAL.29C — to be powered by two 900 hp Bristol Pegasus XC engines.
 

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GAL.30

Type: 5- to 8-seat twin-engined transport aircraft
Powerplants: two 205 hp De Havilland Gipsy Six II engines
Date: 1937
Number built: none
 

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GAL.31

Type: high-wing monoplane freighter
Powerplant: one 300 hp Wasp Junior engine
Date: probably 1937
Number built: none
 
GAL.32
Type: two-seat trainer
Powerplants: one 205 hp De Havilland Gipsy Six II engine
Date: 1937
Number built: none

This was a trainer developed to Spec. T.1/37 in two alternate designs: GAL.32A and GAL.32B.
 

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GAL.33 "Cagnet"

Type: experimental trainer/air observation aircraft
Powerplant: one 90 hp Blackburn Cirrus Minor engine
Date: 1938

A prototype trainer and Flying Observation Platform (FOP) which was aimed at the blossoming Civil Air Guard market. The name "Cagnet" was unofficial.


Number built: 1 prototype [T46=W7645]
 

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GAL.34

Type: twin-engine high-wing transport
Powerplants: two 850 hp Perseus engines (GAL.34A), four 500 hp Aquila engines (GAL.34B)
Date: 1937
Number built: none

This was a twin-engined, high-wing, 14-passenger (18-seat) transport project with retractable undercarriage studied with two different engine arrangements.
 

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GAL.35

Type: remotely-controlled target seaplane
Powerplant: one 205 hp De Havilland Gipsy Six II engine
Date: 1937
Number built: none

This radio controlled target seaplane project, designed to Spec. Q.8/37 (Operational Requirement OR.48) and meant as a Queen Bee replacement, was a mid-wing monoplane of unusual configuration: it featured a single float, a pylon mounted engine and its cockpit was completely integrated to the engine pylon.
 

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GAL.36

Type: twin-engine communications aircraft
Powerplants: two 140 hp Gipsy Six II engines
Date: 1937
Number built: none

This project (Drawing No. A4210) was one of two designs studied to Spec. T.7/37 for a small two-/three- passenger communications type, and resembled the Monospar line of aircraft.

An alternate T.7/37 proposal (Drawing No. A4232, found as "Design B" — which probably meant GAL.36B) was a more angular-looking aircraft, perhaps to be powered by Menasco engines.
 

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GAL.37

Type: twin-engined transport
Powerplants: two 300 hp Jacobs L.5 engines
Date: 1938
Number built: none
 
GAL.38 "Fleet Shadower"

Type: four-engine patrol/reconnaissance aircraft
Powerplants: four 130 hp Pobjoy Niagara V engines
Date: 1938
First flight: May 1940

This three-seat carrier-borne patrol and reconnaissance aircraft of all-wooden construction was built to Spec. S.23/37 (Operational Requirement OR.52) for a "Special Observation Aircraft" — although the unofficial names "Fleet Shadower" or "Night Shadower" were often used to describe it. The type was meant as a slow-flying aircraft with considerable endurance that was to "shadow" warships and keep the fleet informed. However, even after stability was increased by changing from a triple fin configuration to a large single fin, tests were far from convincing, and neither the GAL.38, nor the very similar Airspeed AS.39, built to the same specification, resulted in a production order.


Number built: 1 [P1758]


Specifications
Length: 36 ft 1 in
Height: 12 ft 8 in
Wing span: 55 ft 10 in
Wing area: 472 sq ft
Empty weight: 6153 lb
Loaded weight: 9458 lb

Performance
Maximum speed: 115 mph
Service ceiling: 6000 ft
Duration: 11 hr
 

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GAL.39

Type: carrier-borne general purpose aircraft
Powerplants: two 500 hp Bristol Aquila engines
Date: 1938
Number built: none

This twin-engine Torpedo-Bomber-Reconnaissance-etc. project was designed to Spec. S.30/37 in two variants: the GAL.39A with a 50-foot span, and the GAL.39B, with moveable outer wings (perhaps for dive bombing) and a 44' 9" span. A tricycle undercarriage was required by the January 1938 specification, as well as provision for a floatplane version. Neither the GAL.39 nor the competing Blackburn B.22 resulted in any order.
 

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GAL.40

Type: four-engined transport
Powerplants: four 1050 hp Rolls-Royce Merlin engines (GAL.40A), four 1175 hp Bristol Hercules engines (GAL.40B)
Date: 1938
Number built: none

This design, which featured a pressure cabin and tricycle undercarriage, was submitted to Spec. 15/38 which asked for a long-range, 10- to 30-seat landplane airliner, and was drafted in two variants, GAL.40A and GAL.40B, which differed in the choice of engine types. Four companies responded to the tender, but none of the aircraft was produced, though the Fairey F.C.1 went as far as the full-scale mockup stage before cancellation of the program in October 1939.
 

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GAL.41

Type: twin-engined research aircraft
Powerplants: two 95 hp Pobjoy Niagara III engines
Date: 1938
First flight: 11 May 1939

This experimental prototype was meant for pressure cabin tests with the view to develop the full-sized GAL.40 stratosphere airliner. It was based on the Monospar ST-25 Universal with a completely new forward fuselage integrating a pressure vessel that contained two seats. A 27 hp motor car engine (a Douglas Sprite modified by Aero Engine) was fitted with a supercharger fan to provide pressurization air, was mounted in the extreme nose, maintaining sea-level pressure up to 15,000 ft, with a progressive rate of production above this height. The GAL.41 became the first British airplane to fly with a pressurized cabin.


Number built: 1 [T45=T-0222]

Specifications
Length: 26 ft 4 in
Wing span: 40 ft 2 in

Performance
Cruising speed: 110 mph
Endurance: 3.5 hr
 

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GAL.41

A series of photos of the same GAL.41 prototype in military colors [T-0222].
 

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C-W "Cygnet"

Type: two-seat touring monoplane
Powerplant: 90 hp Blackburn Cirrus Minor (Cygnet Minor), 130 hp de Havilland Gipsy Major (Cygnet Major)
Manufatured by: C-W Aircraft, Sloughs, Bucks.
Date: 1936 (as a C-W product), 1938 (General Aircraft takeover)
First flight: May 1937

Originally NOT a General Aircraft product, this all-metal two-seat touring monoplane prototype was developed by C-W Aircraft, a small firm created by C. R. Chronander and J. I. Waddington, which shared many similarities with the popular Miles Hawk types. It was meant as a design concept for a family of aircraft which C-W was planning to produce (a lot of work was notably done on a twin-engine transport called the Swan). As developed by C-W, the prototype initially featured a raked windscreen, but this was soon changed to a rounded canopy. It can be recognized from the General Aircraft variants by its single triangular fin.

A choice of two engines was planned, resulting in two variants to be designated Cygnet Minor and Cygnet Major. A batch of 20 aircraft had allegedly been ordered but only one prototype was eventually completed. When C-W collapsed in the Spring of 1938, the Cygnet became a General Aircraft product. The specifications below apply to the so-called Cygnet Minor configuration.


Number built: 1 [G-AEMA]


Specifications
Length: 24 ft 3 in
Height: 6 ft
Wing span: 34 ft 6 in
Wing area: 165 sq ft
Empty weight: 1050 lb
Loaded weight: 1600 lb

Performance
Maximum speed: 125 mph
Cruising speed: 105 mph
Climb rate: 750 ft/min
Service ceiling: 20000 ft
Range: 500 miles
 

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GAL.42 "Cygnet" I

Type: two-seat touring monoplane
Powerplant: one 130 hp de Havilland Gipsy Major engine
Date: 1938

This was the former C-W Cygnet design and prototype after being taken over by General Aircraft. It was fitted with the more powerful Gipsy Major engine that was meant for the Cygnet Major configuration; the tail was then modified to twin-fin configuration. The aircraft was further modified by turning the Cygnet into a tricycle undercarriage aircraft. Thus modified, the Cygnet served as a template for the new Cygnet II. Figures below are for the Cygnet Major configuration.


Number built: 1 modified prototype [G-AEMA]


Specifications
Same as C-W Cygnet except
Height: 5 ft 10 in
Empty weight: 1200 lb
Loaded weight: 1900 lb


Performance
Maximum speed: 150 mph
Cruising speed: 128 mph
Climb rate: 850 ft/min
Service ceiling: 17000 ft
Range: 650 miles
 

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