Armstrong Whitworth AW.41 Albemarie

With a possible shortage of light alloys Air Ministry Specification B.9/38 for a twin engined medium bomber, was issued. This required that the aircraft was to be of simple construction, using materials other than light alloy wherever possible. AWA’s chief designer, John Lloyd, and his team were able to submit the initial proposals for their project, the AW.41, to the Air Ministry in February 1938. These initial proposals were for a mid wing monoplane of 61ft 8in span powered by two Rolls Royce Merlin engines and capable of carrying the normal bomb load of 1,500 lb for a range of 1,500 miles cruising at 320 mph at 20,000ft. The sole defensive armament consisted of a four gun power operated turret in the tail. From the outset the AW.41 was to have a retractable tricycle undercarriage. The construction of the airframe was to have been almost exclusively of wood and steel.
The project was changed to meet Specifica¬tion B.18/38 for a twin engined reconnaissance bomber. The design study to meet B.18/38, although using the same type of construction, was very different to the original concept. The wing span was increased to 67ft and the Rolls Royce Merlins were replaced by Bristol Hercules XI radial engines driving three bladed de Havilland constant speed hydromatic airscrews.

On August 18, 1938, Contract 816726/38 was placed with AWA for the manu¬facture of two prototypes.
Construction of the two prototypes was transferred to AWA’s factory at Hamble, and it was provisionally planned that the ensuing production would he undertaken at the new “shadow” factory being built at Yeadon, near Leeds. The plan for Yeadon was abandoned and in November 1939, production contract No B40671/39 for 198 aircraft was placed with Gloster Aircraft at Brockworth. A second contract, No B53250/39 for a further 800 aircraft, was placed with Gloster on January 30, 1940. Shortly after this the Hawker Siddeley Group formed a new com¬pany at Brockworth, A. W. Hawkesley Ltd, to be responsible for the assembly of the AW.41, which by then had been named the Albemarle.

The first prototype, P1360, com¬menced taxiing trials at Hamble on March 18, 1940, and AWA’s chief test pilot, F1t Lt C. K. Turner Hughes, continued the trials of P1360 on March 20, when, after satisfactorily completing the taxiing tests, he carried out a series of straights before taking P1360 off on its maiden flight.

Retraction of the undercarriage was carried out for the first time during the second flight on April 5.
The company’s flight trials showed take off performance to be unsatisfactory and in July and August 1940, P1360 was grounded while the wings were modified, increasing the span by 10ft to 77ft.
In September an A&AEE crew from Boscombe Down started the official performance and handling trials. During a flight on September 30 the pilot became lost and was compelled to make a forced landing in a small field. This was successfully accomplished with only minor damage to the air¬craft.
October was to see further modifica¬tions to P1360, when the areas of the fins and rudders were increased. On November 16 the machine was delivered to the A&AEE at Boscombe Down for continuation of its official trials. It was during a flight from Boscombe Down on February 4, 1941, that a portion of plywood upper skin broke away from the port mainplane. The noise and effect of this led the pilot to believe that the aircraft was having engine trouble, so he immediately shut down the port engine. As a result the aircraft broke away into a spin from which the pilot was unable to recover. He ordered his two observers to abandon the aircraft, and the first cleared the aircraft safely, but the “D” ring of the other’s parachute caught in the fuselage, the observer finding that he was suspended by his harness from the fuselage. The parachute released and developed over the tailplane, acting in an anti spin role and enabling the pilot to regain control.
Unaware of the drama being enacted behind him, the pilot found that he could control the aircraft if he did not allow the speed to fall below 30 or 40kt above stalling speed. With this knowledge the pilot decided to make a wheels up landing, still unaware that his observer was suspended below the fuselage. Just prior to landing, and when he was some 6 to 8ft above the ground, the observer released himself and fell to the ground. Although seriously injured, he survived, the pilot completed his wheels up landing with only minor injuries to himself, although the aircraft was totally destroyed in the ensuing fire.
The second prototype, P1361, first flew on April 20, 1941, continued the flight test programme. This machine also had the 77ft span wing, and was the only Albemarle to be fitted with the ventral power operated turret.
Production problems were caused by over 1,000 sub-contractors who lacked aircraft experi¬ence but were to manufacture all the details and sub assemblies required for the Albemarles. The technical problems with the prototype, particularly the increased wing span, required many of the jigs to be rebuilt.
Only two Albemarles, the prototypes, had flown by June 1941, the first 200 were not completed until March 1943, and production ceased with the completion of the 602nd Albemarle in March 1945. Although contracts were placed for 1,000 Albemarles, this quantity was reduced to 602, including the two prototypes, in June 1943, when it was decided that the facilities at Brockworth were required for Meteor production.
In 1941 the Albemarle programme was investigated by a Select Com¬mittee on National Expenditure, chaired by Sir John Wardlow Milne. The Committee issued its report on August 20, 1941, and it concluded that the Albemarle was not value for money, calling for immediate and urgent reconsideration of the programme.” It is interesting to note that an Albemarle airframe, less engines and equipment, cost £24,950, compared with £19,159 for a Lancaster.
The Prime Minister, Winston Churchill, was concerned about the Committee’s findings, and on August 26, 1941, asked the Secretary of State for Air to provide him with the current views and intentions of the departments involved with the Albemarle. Explanations from the Air Staff and the Ministry of Aircraft Production, defending the Albernarle and their decisions made in regard to it, did not appear to satisfy Churchill, and it apparently took a letter from Lord Beaverbrook on October 12 to finally reassure him. In his letter, Beaverbrook advised that the Alhemarle would be useful for short-range work, and would supplement the Wellingtons in attacks on invasion ports, for bombing in France and for bombing in the event of an invasion. He also explained that the tooling was practically complete at a cost of over £1,500,000, and that more than 75 per cent of the raw materials had been delivered and 50 per cent of the details manufactured.
Deliveries of production aircraft from Brockworth commenced in September 1941, although it was not until June 1942 that monthly deliveries exceeded double figures, with 14 air¬craft being delivered. The first 32 production aircraft were completed as B.Mk.1’s, but the delays had already rendered the Albemarle obsolete as a bomber, and consequently no further aircraft were completed as such, all subsequent machines being produced as glider tugs or special transports.
Projects to cater for any shortage of Hercules engines that may have arisen were the Mk.III with Merlins and the Mk.IV with Wright GR2600 Double Cyclone engines. Cyclones were installed in Mk.I P1406, and a single GTIV, V1760, was completed. The Merlin installation was not proceeded with.

Albemarle I V1599 was experimentally fitted with a long travel undercarriage by AWA during 1943. This was to enable it to fly directly on to the ground without the necessity of a flare out before touch down. Flight testing commenced on November 8, 1943, but it did not prove to be a complete success because the undercarriage oleos failed to compress sufficiently under drag load during flight.
600 Albemarles were produced between 1941 and 1943.
It was widely used as a glider tug, although it suffered from overheating through sustained high power at low airspeed.
There were many GT (general transport) and ST (special transport) versions, some equipped with four gun dorsal turrets (a few had a two gun belly turret) or twin manually aimed dorsal guns. Most could carry freight, paratroops or special equipment. The first ST.I and GT.I entered RAF service in mid-1942 and early 1943 respectively, and subsequent versions brought the total number of Albemarles built to 600.
One batch was supplied to the Soviet Union.

The Albemarle took part in the invasion of Sicily to which they were used to tow support gliders into action. Additionally, the aircraft took part in the D-Day invasion landings of June 1944 (again as glider tugs) and served with airborne elements during the airdrops over Arnhem campaign to end the war before Christmas.

Gallery

Armstrong Whitworth AW 41 Albemarle
Engine: 2 x Bristol Hercules XI, 1568 hp
Length: 59 ft 11 in / 18.26 m
Height: 15 ft 7 in / 4.75 m
Wingspan : 77.00 ft / 23.47 m
Wing area : 803.533 sqft / 74.65 sqm
Max take off weight : 22603.5 lb / 10251.0 kg
Max. speed : 230 kts / 426 km/h
Cruising speed : 148 kts / 274 km/h
Service ceiling : 17995 ft / 5485 m
Wing load : 28.09 lb/sq.ft / 137.00 kg/sq.m
Range : 1130 nm / 2092 km
Crew : 4
Armament: 2x cal.303 MG Vickers “K” (7,7mm)

Armstrong Whitworth AW.38 Whitley

Whitley V

Air Ministry Specification B.3/34 called for a bomber that could carry a bomb load of 2000 lbs for 1250 miles at a height of 15,000 feet at a maximum speed of 225 mph. As the RAF’s existing hangar doors were little more than 100 feet wide, putting a firm limit on the aircraft’s wingspan which was only 84 feet but with a wide chord and thick wing section. There were four contenders to build to specification B.3/34 with Armstrong Whitworth becoming the chosen company. The A.W.38 (which was later named Whitley after the airfield and works near Coventry) contained design features that had previously been tested by the company in the A.W.23 transport/bomber. The new light alloy wing construction consisting of a basic torsion box of web corrugated vertically, and spanwise gave it strength aided by an internal bracing of steel struts.

Armstrong Whitworth Whitley Article

The prototype Whitley, K4856, was first flown on March 17, 1936. With increasing urgency for the RAF to re-equip and after an original order for 80 aircraft, a second order for 240 Whitleys was signed on 13 May 1936, two months after the prototype’s first flight.

The second prototype and 34 Mk I production aircraft which followed were all powered by two 592.5kW Armstrong Siddeley Tiger IX radial engines. The first production Whitley, K7183, was delivered in the early months of 1937, with the second aircraft, K7184, being flown direct on March 9 from Baginton to No 10 Squadron, which was then equipped with Handley Page Heyfords.

The original design had no wing flaps but later flaps – with a maximum deflection of 60o – were incorporated.
With a wing area of over 1,200 square feet and a high angle of attack, the type had superb lift, but the original power plants – 795 hp Armstrong Siddeley Tiger IX air cooled radials – left the early Marks of Whitley under-powered. Half way through the first production batch, after 34 aircraft had been completed, the Whitley 1 was superseded by the Mk II version in which the 795 hp Armstrong Siddeley Tiger IX engines were replaced by 845 hp Tiger VIII engines incorporating a two speed supercharger.

The Mk III would appear shortly after the initial batch, introducing a Nash & Thompson ventral gun position that was retractable.

The need for still more performance and greater reliability resulted in a decision to adopt 1,745 hp Rolls Royce Merlin Xs for the Mk IV. The first Merlin powered example flew on February 11, 1938. A subvariant of the Mk IV would appear with a newly-configured powered tail turret housing quad 7.7mm machine guns.

The first Mark V came off the line on 28 August 1939 and production of this Mark lasted four years and accounted for 90 percent of the total number of type built; over 2,000 in all.

Whitley V of 78 Sqn, RAF

At the outbreak of the Second World War almost all of the Whitley Is and IIs had been withdrawn from operational status as heavy bombers, although seven squadrons (Nos 10, 51, 58, 77, 78, 97 and 102) were equipped with the Mk IIIs, IVs or Vs.

102 Sqn Whitley leaflet dropping

After the introduction of four engined bombers such as the Halifax, Stirling and Lancaster during 1940 41 Whitleys continued bombing operations over Germany until April 1942 the last raid taking place on April 29 30 to Ostend.

At the end of the war the type was still in service for training and other miscellaneous duties.
The Whitley was responsible for the first bombing raid on Germany, in May 1940; the first bombing raid on Italy, in June 1940; and the first paratroop operation over Southern Italy, in February 1941.
The last Whitley built, LA951, was retained by the Armstrong Whitworth company on its completion in 1943. It was used for general test and experimental flying, one of its main tasks being to act as a tug for the A.W.52G glider. Four years later, in March 1949, LA951 was withdrawn from service and dismantled.

Gallery

Whitley Mk I
Engines: 2 x Armstrong Siddeley Tiger IX, 795 hp / 592.5kW

Whitley Mk II
Engines: 2 x Armstrong Siddeley Tiger VIII, 845 hp

Whitley III
Engines: 2 x Armstrong Siddeley Tiger VIII, 920 hp.
Max speed: 215 mph
Cruise speed: 177 mph
Range: 1300 mi

Whitley IV
Engines: 2 x Rolls-Royce Merlin, 1030 hp
Wingspan: 84 ft 0 in
Length: 70 ft 6 in
Max speed: 245 mph
Cruise: 215 mph
Normal range: 1250 mi
Max range: 1800 mi

Whitley V
Engines: 2 x Rolls-Royce Merlin X, 840kW / 1,145hp
Wingspan: 25.6 m / 84 ft 0 in
Length: 21.5 m / 72 ft 6 in
Height: 4.6 m / 15 ft 1 in
Wing area: 114.4 sq.m / 1231.39 sq ft
Maximum Take-off weight: 12800 kg / 28219 lb
Empty weight: 8770 kg / 19335 lb
Wing load : 29.52 lb/sq.ft / 144.0 kg/sq.m
Fuel cap: 837 Imp.gal.
Max. speed: 357 km/h / 222 mph
Cruise speed: 297 km/h / 185 mph
Rate-of-Climb: 938ft/min (286m/min)
Op. Ceiling: 5360 m / 17600 ft
Service ceiling: 26,000 ft / 7,925m
Range w/max.fuel: 2600 km / 1616 miles
Range w/max.payload: 760 km / 472 miles
Armament:
1 x 7.7mm machine gun in nose turret
4 x 7.7mm machine guns in tail turret
Bombload: 7,000lb / 3150kg
Crew: 4-6

Armstrong Whitworth AW.35 Scimitar

A development of the A.W.16, the A.W.35 Scimitar was powered by a Panther VII engine enclosed by a long-chord cowling and rated at 565hp at 3660m, and a maximum output of 605hp at 4115m. Armament was two 7.7mm Vickers Type E machine guns and provision was made for four 9kg bombs to be carried beneath the lower mainplane.
Two prototypes of the Scimitar were flown in 1933, and these were followed by four production examples for the Norwegian Army Air Force which were delivered at the beginning of 1936. These were powered by the Panther XIA with a maximum rating of 730hp.

Engine: Panther XIA, 730hp
Take-off weight: 1860 kg / 4101 lb
Empty weight: 1276 kg / 2813 lb
Wingspan: 10.06 m / 33 ft 0 in
Length: 7.62 m / 25 ft 0 in
Height: 3.53 m / 11 ft 7 in
Wing area: 24.28 sq.m / 261.35 sq ft
Max. speed: 343 km/h / 213 mph

Armstrong Whitworth AW.27 Ensign

The Ensign class of airliner was designed to an Imperial Airways specification for an aircraft capable of operating Empire routes to South Africa and Australia. The aircraft was proposed in two forms: the 40-seat ‘European’ or ‘Western’ (with 12 passengers in the front cabin, 4 in the card room, 12 in the middle cabin and 12 in the rear cabin, plus 3 toilets) and the 27-seat ‘Empire’ or ‘Eastern’ (with 3 cabins and 2 toilets) which could also be configured as a 20-passenger sleeper. Both versions were externally similar, being shoulder-wing monoplanes with the four 596kW Armstrong Siddeley Tiger IX radial engines mounted in the leading edges of the wings. The fuselage had a retractable undercarriage, each main leg carrying a single large Dunlop wheel.

The design was accepted and development proceeded, albeit at a interrupted pace thanks to the changing requirements put forth by Imperial Airways, coupledd with early engine reliability issues.

Design of the Ensign was characterized by its smooth lines and high-wing mounting. The cockpit was situated at extreme forward offering up good views past the wings which were seated to the middle of the fuselage, far back from the cockpit. Oval-shaped windows dotted the fuselage sides while the fuselage bottom sagged from nose to tail tip. The main landing gear were housed in the wing roots and consisted of large donut type wheels consistent with large aircraft design of the times. Four engines were placed two to a wing in the leading wing edges and contoured nicely into the wing elements. The empennage was of a traditional layout complete with rounded fin edges. Crew accommodations amounted to five personnel that included the pilot, co-pilot, radio operator and – if needed – two cabin stewards for passenger flight. Depending on the required range, passenger seating numbers fell between 27 and 40 total personnel.

The first A.W.27 flew on 23 January 1938 and from October it flew the London-Paris service. Production was slow but three more were completed in time for mail-carrying flights to Australia in late 1938. Due to engine troubles, all broke down well short of their goal.

The sixth production A.W.27 was fitted with 637kW Tiger IXC engines driving new de Havilland three-blade constant-speed propellers, and had a modified tail unit. This arrangement became standard on all the A.W.27s.

With the outbreak of World War II the A.W.27s were used to ferry RAF personnel initially to France and then between RAF stations within the UK with No. 24 Squadron. During this period several were destroyed or damaged by German fighters. In 1941 the surviving aircraft were re-engined with 671kW Wright R-1820-G102A Cyclone radials and were known as A.W.27A Ensign Mk IIs.
The AW.27 appeared in a single captured form with the Vichy French and later the Luftwaffe.
With the end of the war the airliners were scrapped.
Altogether 14 A.W.27s had been built.

Armstrong Whitworth AW 27 A Ensign
Engine: 4 x Armstrong Siddeley Tiger IX, 779 hp
Length: 114.173 ft / 34.8 m
Height: 23.031 ft / 7.02 m
Wingspan: 123.032 ft / 37.5 m
Wing area: 2449.886 sqft / 227.6 sq.m
Max take off weight: 48951.0 lb / 22200.0 kg
Weight empty: 32854.5 lb / 14900.0 kg
Max. payload weight: 9569.7 lb / 4340.0 kg
Max. speed: 177 kts / 328 km/h
Cruising speed: 147 kts / 272 km/h
Service ceiling: 18012 ft / 5490 m
Cruising altitude: 7005 ft / 2135 m
Wing load: 20.09 lb/sq.ft / 98.0 kg/sq.m
Range: 695 nm / 1288 km
Crew : 3+2
Payload : 27 pax

Armstrong Whitworth AW 27 A Ensign
Engines: 4 x Armstrong Siddeley Tiger IXC, 634kW
Take-off weight: 22226 kg / 49000 lb
Empty weight: 14392 kg / 31729 lb
Wingspan: 37.49 m / 122 ft 12 in
Length: 34.75 m / 114 ft 0 in
Height: 7.01 m / 22 ft 12 in
Wing area: 227.61 sq.m / 2449.97 sq ft
Max. speed: 330 km/h / 205 mph
Cruise speed: 274 km/h / 170 mph
Ceiling: 5485 m / 18000 ft
Range: 1384 km / 860 miles

Armstrong Whitworth AW.27 Ensign Mk I
Engines: 4 x Wright GR-1820-G102A radial, 1,100hp
Length: 114.17 ft (34.8m)
Wing span: 123.03 ft (37.50m)
Height: 23.03 ft (7.02m)
Maximum Speed: 205mph (330kmh; 178kts)
Maximum Range: 1,367miles (2,200km)
Rate-of-Climb: 900ft/min (274m/min)
Service Ceiling: 23,950ft (7,300m)
Accommodation: 5 + 27 to 40 passengers
Empty Weight: 35,053 lbs (15,900kg)
Maximum Take-Off Weight: 55,556 lbs (25,200kg)

A.W.27A Ensign Mk II
Engines: 4 x 671kW Wright R-1820-G
Wingspan: 37.49 m / 122 ft 12 in
Length: 34.75 m / 114 ft 0 in
Height: 7.01 m / 22 ft 12 in
Wing area: 227.61 sq.m / 2449.97 sq ft

Armstrong Whitworth Atlas

The Armstrong Whitworth Atlas was designed to replace the de Havilland DH.9A biplane of 1918 as well as the Bristol Fighter of 1916 against the RAF requirements of Specification 20/25. The Atlas design was intended to replace both airframes as the primary RAF “army co-operation” (mission liaison) mount. The Atlas was attributed to an engineering team led by John Lloyd who headed up design at the Armstrong Whitworth Aircraft firm as its Chief Designer.

Armstrong Whitworth and Lloyd’s design team initially undertook the Atlas project as a private venture, the prototype first flying on May 10th, 1925. The RAF then accepted the prototype for evaluation against other aircraft and the two-seat Atlas biplane proved a sound design save for some noticeable “sideslipping”. The issue was resolved with the fitting of new metal wings that featured sweepback. However, the new wings degraded the quality of the aircraft’s in-flight handling – then deemed excellent – and now showcased poor stall characteristics as well. As such, automatic slats were added to the wings and sweep was increased to an extent and, in the case of aircraft for the RCAF, the addition of ailerons on the lower wings. This rectified the less-than-stellar handling characteristics caused by the wing change.

Design was highly conventional for the time. The aircraft mounted its engine in a forward compartment to power the propeller system. The steel tube fuselage (fabric covered) was rather rounded in shape, thicker forward and tapering off at the rear. The wings were of an unequal span, single-bay biplane assemblies made of metal sporting slight dihedral on each unit, moreso in the lower assembly. The pilot sat direct aft of the upper wing assembly in an open-air cockpit with his observer/gunner in an open-air cockpit aft of the pilot. The empennage was relatively conventional in design, featuring a rounded vertical tail fin with a pair of horizontal stabilizers. The undercarriage varied based on sortie need – either a pair of wheels were set in a fixed undercarriage for land-based assignment or a set of long-running pontoon floats could be installed for at-sea work. Either way, the empennage was supported by a simple tail skid made particularly suitable for the land-based model. A hook could be optionally fitted to the fuselage underside to make quick pick-ups of ground messages without having the aircraft be required to land.

Standard armament for the series centered around a pairing of machine guns. A .303in (7.7mm) Vickers type machine gun was in a fixed position set to fire forward. A .303 (7.7mm) Lewis machine gun was mounted on a “Scarff ring” in the rear cockpit for trainable fire against emerging enemy threats from the rear. The flexible Scarff ring was developed in World War 1 by Britain Warrant Officer (Gunner) F.W. Scarff to address the armament needs of a rear gunner faced with the prospect of fighting the enemy from multiple angles from his open-air cockpit. In addition to the machine guns, the Atlas could be fitted with 112lb bombs under the wing elements.

Production of the Atlas began soon after with the aircraft formally introduced for service with the British Royal Air Force in 1927, an initial production batch numbering 37 aircraft. The Atlas entered service with 13 Squadron and 26 Squadron immediately and was eventually fielded with the overseas 208 Squadron out of Heliopolis, Egypt in 1930. It served in the mission liaison role – as well as trainer and communications – up until she was retired in 1935.

The initial production model became the Atlas I and some 271 examples were delivered to the RAF. Production lasted from 1927 to 1933 to which 478 were ultimately produced. 175 were dual-control advanced trainers.
The Atlas Trainer served as a dual-control mount in the training of future Atlas pilots.

These aircraft were to remain in service until 1934 in the army cooperation role, and as advanced trainers and communications aircraft into 1935.

Beyond British use, the Atlas was in the inventories of Canada, Egypt and Japan. The Atlas was eventually superseded by the Hawker Audax, based on the Hawker Hart biplane, and its trainer derivatives were themselves replaced by the Hawker Hart Trainer.

The Atlas II soon appeared as an improved Atlas model with more output from its Armstrong Siddeley Panther IIA engine of 525 horsepower/399kW, radio, message pick-up hook and cameras. However, the RAF elected to go with the competing Audax design and 15 of this model were delivered to the Chinese Air Force. Ajax represented Atlas I models with slight variations and only 4 were ever built for the RAF. Aries was a proposed and improved Atlas I model with slightly larger surfaces and overall dimensions while also being made easier to maintain in the field. However, only one was ever completed. The EAF Atlas was an export product for the Greek Air Force (Hellenic Air Force) that primarily differed in its selected engine, propeller and wing assemblies. At least 10 of this model were locally built by EAF (State Aircraft Factory) in Greece after 1931.

The last Armstrong Siddeley Atlas in RAF service was fielded by 208 Squadron, which replaced their aircraft with the newer Hawker Audax in 1935. Privately-held Atlas aircraft operated until 1938.

Atlas Mk I
Engine: 1 x Armstrong Siddeley Jaguar IVC, 450hp / 298kW.
Length: 28 ft 6.6 in (8.68m)
Wing span: 39 ft 6.6 in (12.04m)
Height: 10 ft 6 in (3.20m)
Empty Weight: 2,557 lbs (1,160kg)
Maximum Take-Off Weight: 4,028 lbs (1,827kg)
Endurance: 3.5 hr
Maximum Speed: 142mph (229kmh; 124kts)
Maximum Range: 400miles (644km)
Service Ceiling: 16,798ft (5,120m; 3.2miles)
Armament: 1 x 7.62mm Vickers mg, 1 x 7.62mm Lewis mg position
Up to 4 x 50kg bombs underwing
Crew: 2
Hardpoints: 4

Atlas Mk II
Engine: 399kW Panther IIA

Armstrong Whitworth AW.19

Air Ministry Specification G.4/31 called for a General Purpose aircraft, capable of level bombing, army co-operation, dive bombing, reconnaissance, casualty evacuation and torpedo bombing. The Vickers Type 253 won against the Fairey G.4/31, Westland PV-7, Handley Page HP.47, Armstrong Whitworth AW.19, Blackburn B-7, Hawker PV-4 and the Parnell G.4/31.
One prototype, first flown on 26 February 1934. No production.

Engine: 1 x 810hp Armstrong Siddeley Tiger VI
Take-off weight: 3969 kg / 8750 lb
Empty weight: 1950 kg / 4299 lb
Wingspan: 15.14 m / 49 ft 8 in
Length: 12.85 m / 42 ft 2 in
Height: 3.96 m / 12 ft 12 in
Wing area: 60.78 sq.m / 654.23 sq ft
Max. speed: 262 km/h / 163 mph
Ceiling: 6400 m / 21000 ft

Armstrong Whitworth AW.16

The Specification 21/26, issued by the Air Ministry’s Directorate of Technical. Development (DTD) on September 30, 1926, called for a “Single Seater Fighter Ship¬-plane for use from HM ships,” fitted with a land undercarriage which could be replaced by floats, and vice versa, within half an hour. The aircraft, which was to have an all metal structure but could be fabric covered, was to be suitable for launch from a catapult and for taking off from and alighting on the deck of an aircraft carrier.
Engines specified were the air cooled Bristol Mercury radial giving 550hp at 2,000rpm or the water cooled Rolls Royce Falcon X giving 480hp at 2,300rpm. A metal propeller was specified.
There was to be tankage for 74 gallons of fuel, plus an easily removed 20 gallon auxiliary tank and a gravity tank of sufficient capacity to allow half an hour’s flight at full power at ground level. An 11 gallon oil tank was to be provided if the Mercury engine was used, or an 8.5 gallon oil tank and a 2.5 gallon reserve water tank for the Falcon.
Alternative exhaust systems for day or night flying were required, and were to be easily changed.
Additional equipment to be carried during the acceptance flights weighed 5581b and included a Vickers 0.5in gun and 300 rounds, a Vickers 0.303in gun and 600 rounds, a rocket launching (R/L) tube and six bombs, and flotation gear. A second 0.303in gun with 600 rounds was to be provided for if the 0.5in gun was not available in time.
Minimum performance requirements with this load, using the Mercury, called for a horizontal speed of 132kt (152mph) at 10,000ft and a service ceiling of 23,000ft. With the Falcon X the figures were 127kt (146mph) at 10,000ft and 22,000ft. The length of run to take¬off was not to exceed 47ft in a relative wind of 28kt (32mph), and the aircraft was to become airborne at a speed of 55mph when catapulted in still air. The suitability for launching from a catapult or alighting on the deck of an aircraft carrier was “of first importance”, and the aircraft had to be capable of taking off from a turret or cruiser platform.
Despite the emphasis placed on the machine’s naval use, it was stressed that: “The aircraft is to be designed primarily as a landplane fighter and qualities required for this work are not to be sacrificed in order to improve its characteristics when equipped with the float alighting gear”.
A limit of 35ft was put on the wing span, the overall length was restricted to 23ft, the height was not to exceed 14ft 9in. Quick and easy removal and erection of the wings was specified, with the ability to remove the wing structure completely in ten minutes and replace it in fifteen minutes.
Tendering for this demanding specification were Armstrong Whitworth, which offered the AW XVI; Fairey, with the Flycatcher II; Gloster, which tendered the Gnatsnapper; Hawker, which offered the Hoopoe; Vickers, with a modified version of its Type 141 Scout; and George Pamall & Co.
Developed as a private venture to meet the requirements of both N.21/26 and F.9/26, the A.W.16 appeared in 1931. Two prototypes were flown. The first conforming to N.21/26 and the second to F.9/26, both being initially powered by the geared and supercharged Panther IIIA of 540hp. The second prototype was re-engined with a 565hp Panther VII during the course of trials at the A & AEE in 1933. Eighteen production examples of the A.W.16 were produced late in 1931, 17 of these for delivery to the Chinese Kwangsi Air Force and one being used as an engine test bed before being passed to the Alan Cobham circus. Armament comprised two 7.7mm Vickers machine guns.

Engine: Panther IIIA, 540hp
Take-off weight: 1597 kg / 3521 lb
Wingspan: 10.06 m / 33 ft 0 in
Length: 7.62 m / 25 ft 0 in
Height: 3.50 m / 11 ft 6 in
Wing area: 24.24 sq.m / 260.92 sq ft
Max. speed: 322 km/h / 200 mph