This is a partial list of the British Air Ministry (AM) specifications for aircraft. A specification started from an Operational Requirement, abbreviated "OR", describing what the aircraft would be used for - this in turn led to a specification e.g. a two engined fighter with 4 machine guns. So for example, OR.40 for a heavy bomber led to Specification B.12/36. Aircraft manufacturers would design and build aircraft which the Ministry then bought for evaluation by the RAF. On very rare occasions, a manufacturer would design and build an aircraft using their own money as a "Private Venture" (PV). This would then be offered to the Ministry for evaluation. If the aircraft generated interest in the Ministry or RAF due to performance or some other combination of features then the Ministry might well bring out a specification based on the Private Venture aircraft.

The system of producing aircraft to a specification ran from 1920 to 1949 during which the Air Ministry was replaced by first the Ministry of Aircraft Production (MAP) and then the Ministry of Supply (MoS). The system was applied to commercial aircraft as well - one of the last being the Bristol Brabazon. During the period, over 800 specifications were issued.

Specification designations

Each specification name usually followed a pattern. A leading letter was usually present to identify the aircraft purpose. The codes used included B for "heavy bomber", P for "medium bomber", F for "fighter" and A for "army co-operation". The second part was a number identifying it in sequence and then after the slash, the year it was formulated, so in the example given above, B.12/36 signifies the twelfth bomber specification issued in 1936. Specifications were not always issued in sequence.

Admiralty specifications were identified by the letter N (Naval) and experimental specifications identified by the letter E (Experimental), with training aircraft signified by the letter T (Training) and unpowered aircraft, i.e., gliders, signified by the letter X. The letter G (General) signified a general-purpose aircraft, with an M (Multi-role) being applied to aircraft intended for more than one specific purpose.

The letter C (Cargo) was applied to military transport aircraft, with the letter O (Observation) used for a naval reconnaissance aircraft - the letter S (Spotter) used for the more specialised role of naval spotting, i.e., observing and reporting back the fall of naval gunfire - and R (Reconnaissance) for a reconnaissance type - often a flying boat. Special purpose aircraft would be signified by a letter Q, this being used to specify aircraft such as target-tugs, radio-controlled target drones, etc.

Sometimes the purpose for which an aircraft is used in service would change from that for which the specification to which it was designed was issued, and so there are some discrepancies and inconsistencies in designation, the Royal Navy in particular liking to specify multiple roles for its aircraft in an attempt to make the best use of the necessarily limited hangar space onboard its aircraft carriers. In this case this resulted in several types designed to specifications originally intended to signify the naval Spotting role also being used for other purposes, e.g., S.15/33, resulting in the Blackburn Shark and Fairey Swordfish, the latter aircraft being primarily utilised as a torpedo bomber. Similarly S.24/37, which produced the Fairey Barracuda, again primarily designed for spotting, the dive bomber/torpedo bomber requirements being regarded as secondary when the specification was issued, but for which roles it was almost exclusively subsequently used, the original spotting requirement having been made obsolete with the introduction of radar.

In addition, some (mostly early) specifications appear to have no letter prefix at all, e.g., 1/21, the Vickers Virginia III.

List of specifications (incomplete)

The names of the aircraft shown in the table are not necessarily those they carried when provided for evaluation as at this point an aircraft would usually be referred-to as the Manufacturer X.XX/XX, e.g., the Avro B.35/46 - this is in addition to the manufacturer's own separate internal designation for the aircraft, e.g., Avro 698. With several manufacturers submitting designs to the same specification this could result in a number of different aircraft with the same X.XX/XX designation, e.g., Handley Page B.35/46, etc.

Upon acceptance of the design(s) the final service names would usually be chosen by the Air Ministry when they placed a production order, in the above B.35/46 cases, where two aircraft were accepted to this specification, Vulcan and Victor respectively.

Upon entering service, in the absence of any already-planned variants a new type would initially have no Mark Number after the aircraft name, being simply referred-to as the Manufacturer Service-name, e.g., the Avro Anson, however upon acceptance of a new variant the previous (initial) version automatically became the 'Mark I', so in the example given, the previous (first) version of the Anson retrospectively became the Avro Anson Mk I upon acceptance of an Avro Anson Mk II. Sometimes planned variants would be later cancelled leading to 'missing' Mark Numbers, or the extent of the changes may have justified given the new variant a completely new name, e.g., the Hawker Typhoon II subsequently becoming the Hawker Tempest, or the Avro Lancaster B.IV & B.V entering service as the Avro Lincoln. Typographical designation of Mark Numbers (Mk.) varied over time and inconsistencies are common, e.g., Mark II, Mk. II, II, etc. Initially Roman numerals were used, changing to Arabic numerals post-World War II, e.g., Supermarine Spitfire Mk I to Supermarine Spitfire Mk 24.

Main article: British military aircraft designation systems

Note 1: where possible Mark Numbers are given here in this list in the form that was used at the time of acceptance. Variations may be encountered due to changes in format/typographical convention over time.

Note 2: due to mergers and amalgamations within the UK aircraft industry sometimes the name of the manufacturer changed over time, e.g., English Electric later became part of the British Aircraft Corporation (BAC), so the English Electric Lightning then became the BAC Lightning; the British Aircraft Corporation itself and Hawker Siddeley (HS) then later merged and became British Aerospace, subsequently becoming BAe (now BAE Systems). Thus the previously mentioned Avro Vulcan was subsequently referred-to as the Hawker Siddeley Vulcan; similarly, the Blackburn Buccaneer later became the Hawker Siddeley Buccaneer. Where possible, for clarity the aircraft in this list are listed under the ORIGINATING company's name or the name of the manufacturer under which it first entered production.

Specifications within the tables are listed by year of issue and in numerical and alphabetical order. Specifications lacking a letter-prefix or where one is not currently known are listed first at the beginning of each year's entries before those with a letter-prefix.

1920-1929

Spec.	OR	Type	Designs (accepted and tendered)
1/20	None	First spec. issued: spares carrier	Bristol Type 37 Tramp
2/20		'Interim' single-engine heavy bomber	Avro Aldershot, de Havilland Derby
3/20		Single-seat deck-landing torpedo-carrier - Spec. superseded by 32/22 (q.v.)	Blackburn Dart (modified), Handley Page H.P.19 Hanley
1/21		Long-range bomber - Vimy replacement	Vickers Virginia III
2/21		Experimental single-seat convertible biplane/monoplane fighter/interceptor/two seat reconnaissance-fighter aircraft - written for Bullfinch	Bristol Bullfinch
3/21		Naval Fleet spotter/reconnaissance aircraft	Avro Bison
5/21		Light day bomber - DH.9A replacement	Fairey Fawn
19/21		Two-seat reconnaissance aircraft - Bristol Fighter replacement	Short Springbok
3/22		Two seat fighter/reconnaissance powered by a supercharged engine - Bristol Fighter replacement	Bristol Bloodhound
6/22		Naval carrier fighter with interchangeable wheel & float undercarriages using Jaguar or Jupiter engine - Nightjar replacement	Fairey Flycatcher, Parnall Plover
7/22		Army reconnaissance aircraft	Hawker Duiker
16/22		Long range Torpedo Bomber to carry 21 inch torpedo	Blackburn Cubaroo, Avro 557 Ava
21/22		Twin-engined amphibian flying boat for civil operations - see also R.18/24	Supermarine Swan
22/22		Two seat fighter/reconnaissance powered by a supercharged engine - Bloodhound three aircraft order - revised from 3/22 (q.v.)	Bristol Bloodhound
31/22		4-seat heavy night-bomber	Handley Page Hyderabad
32/22		Single-seat deck-landing torpedo-carrier - Spec. supersedes 3/20 (q.v.)	Blackburn Dart II
37/22		fleet reconnaissance biplane	Hawker Hedgehog
38/22		General Purpose seaplane/landplane	Fairey IIID
41/22		'Middle East type transport aeroplane' - civil airliner	Armstrong Whitworth Argosy, de Havilland Hercules
B.30/22		Heavy bomber - written for Bugle II production order but Sidestrand also apparently designed to this spec.	Boulton Paul Bugle II, Boulton Paul Sidestrand
16/23	None	Spotting ship-plane	Avro Bison
21/23		Fleet two-seat torpedo bomber	Avro Buffalo, Blackburn Ripon, Handley Page H.P.31 Harrow
25/23		Fleet two-seat torpedo bomber/bomber	Handley Page H.P.25 Hendon
26/23		Two-seat long-range day-bomber	Bristol Berkeley, Handley Page H.P.28 Handcross, Hawker Horsley, Westland Yeovil
4/24		"Twin-Engined Home Defence Fighter" armed with two 37 mm cannons	Westland Westbury Bristol Bagshot
7/24		'High Powered Single-Seater Fighter Landplane'	Avro Avenger, Fairey Firefly, Fairey Fox, Gloster Gorcock, Hawker Hornbill
9/24		Twin engine medium day-bomber - Sidestrand II production order - see also 25/27	Boulton Paul Sidestrand II
13/24		Patrol flying boat	Blackburn Iris III, Short Singapore
15/24		4-seat heavy night-bomber - initial production batch of Hyderabads	Handley Page Hyderabad I
16/24		Submarine-borne reconnaissance seaplane	Parnall Peto
19/24		Three-seat Spotter/Reconnaissance (FAA) /two-seat GP (RAF) aircraft with interchangeable land & float U/C & folding wings	Fairey IIIF
23/24		Twin engine civil airliner	Handley Page H.P.32 Hamlet
27/24		Twin engine single seat interceptor	Boulton Paul Bittern
28/24		Day and night fighter - Siskin replacement	Armstrong Whitworth Starling
30/24		Two-seat reconnaissance/army co-operation aircraft	Short Chamois, Vickers Vespa
R.18/24		Twin-engined amphibian flying boat - military version of boat ordered to 21/22	Supermarine Southampton
17/25		Naval single-seater fighter monoplane	Avro 584 Avocet, Vickers Vireo
20/25		Army co-operation aeroplane - Bristol Fighter/DH.9A replacement	Armstrong Whitworth Atlas, Bristol Boarhound
23/25		Two-seat day-bomber	Gloster Goring, Handley Page H.P.34 Hare, Hawker Harrier, Westland Witch
24/25		Torpedo-bomber - Horsely replacement	Vickers Vildebeest
12/26		Fast two-seat day bomber of all-metal construction using Rolls-Royce F.XIB engine	Avro Antelope, Hawker Hart, Fairey Fox II
14/26		Passenger flying boat	Short Calcutta
21/26		Naval Fleet fighter	Parnall Pipit
F.9/26	None	Day and night 'zone' fighter - no design accepted and Spec. superseded by F.20/27 (q.v.)	Armstrong Whitworth Starling II, Bristol Bulldog Mk.I, Bristol Bullpup, Gloster Goldfinch, Gloster SS.18, Hawker Hawfinch, Blackburn Turcock
N.21/26		Naval Fleet fighter	Armstrong Whitworth Starling II, Armstrong Whitworth AW XVI, Blackburn Turcock, Gloster Gnatsnapper, Hawker Hoopoe, Vickers Type 177
O.22/26		Naval high-speed, two-seat, Fleet fighter/reconnaissance	Blackburn Nautilus, Fairey Fleetwing, Handley Page H.P.37F, Hawker Osprey, Short Gurnard
25/27		Twin engine medium day-bomber - Sidestrand II production order - see also 9/24	Boulton Paul Sidestrand II
26/27		General purpose aircraft - D.H.9A replacement	Bristol Beaver, de Havilland Hound, Fairey Ferret, Gloster Goral, Vickers Valiant, Vickers Venture, Vickers Vixen, Westland Wapiti
33/27		'Postal Aircraft' - experimental very-long range aeroplane for world distance-record attempt	Fairey Long-range Monoplane
B.19/27		Twin engine night-bomber - Virginia/Hinaidi replacement - Hendon winner but introduction delayed so runner-up (Heyford) accepted	Fairey Hendon, Handley Page Heyford, Vickers Type 150
B.22/27		Three engine night-bomber - abandoned due to delays and replaced by B.19/27 (q.v.)	Boulton Paul P.32, de Havilland D.H.72 Canberra
C.20/27		Transport version of Hyderabad/Hinaidi - Chitral/Clive	Handley Page Clive
F.20/27		'Interception single-seat fighter'	Armstrong Whitworth Starling II, Bristol Bulldog Mk.II, Fairey Firefly II, Hawker Fury, Vickers Jockey, Westland Interceptor
F.29/27[1]		Fighter utilizing a 37 mm cannon from Coventry Ordnance Works	Vickers Type 161, Westland C.O.W. Gun Fighter
R.5/27		Reconnaissance flying boat	Blackburn Sydney
21/28		High-speed mailplane for Imperial Airways	Boulton Paul P.64 Mailplane, Boulton Paul P.71A
C.16/28		Bomber-transport	Gloster TC.33, Handley Page H.P.43
F.17/28		Bulldog II production order	Bristol Bulldog Mk.II
M.5/28		Torpedo bomber - Spec superseded by M.1/30 (q.v.)	Handley Page H.P.41
R.6/28		Patrol/reconnaissance flying boat	Short Sarafand
4/29		ab initio trainer - Moth with Gypsy I order	de Havilland Moth
9/29		Fast two-seat day bomber - Hart I production order	Hawker Hart
13/29		4-seat heavy night-bomber - production batch of Hinaidi IIs	Handley Page Hinaidi II
B.10/29		Twin engine medium day-bomber - Sidestrand III production order	Boulton Paul Sidestrand III

1930-1939

Spec.	OR	Type	Designs (accepted and tendered)
3/30		Basic trainer - Avro 504N replacement	Avro Type 621 Trainer
6/30		ab initio trainer - Lynx-Avro (Avro 504N) production order	Avro 504N
8/30		ab initio trainer - Moth with Gypsy II order	de Havilland Moth
9/30		Two-seat carrier-borne torpedo bomber/three-seat Spotter-reconnaissance aircraft	Fairey T.S.R.I ;see also S.15/33
16/30		Naval fighter - written for Nimrod	Hawker Nimrod
18/30		Fairey IIIF replacement	Fairey Gordon I
19/30		Naval fighter/reconnaissance with folding wings and interchangeable wheel/float U/C	Hawker Osprey
F.7/30		Fighter capable of at least 250 mph and armed with four machine guns	Gloster Gladiator, Gloster SS.19, Hawker P.V.3, Supermarine Type 224, Westland F.7/30
M.1/30		Torpedo bomber - Spec. supersedes M5/28 (q.v.)	Blackburn M.1/30, Handley Page H.P.46, Vickers Type 207
13/31		ab initio trainer with complete freedom for parachute escape by both occupants - D.H.60T accepted with modifications, becoming D.H.82 - see also T.23/31	Avro Type 631 Cadet, de Havilland D.H. 60T Tiger Moth
18/31		Basic trainer - Avro Type 621 Trainer with Lynx engine	Avro Tutor
C.26/31	OR.4	Bomber-transport - Valentia replacement	Armstrong Whitworth A.W.23, Bristol Bombay, Handley Page H.P.51. Vickers Type 230 - (not built)
G.4/31		General-purpose/torpedo bomber - Wellesley one of two designs submitted by Vickers and itself a PV	Fairey G.4/31, Handley Page H.P.47, Hawker P.V.4, Parnall G.4/31, Vickers G.4/31, Vickers Wellesley, Westland PV-7
R.20/31		Twin-engined flying boat - all-metal Kestrel-engined Southampton II (Southampton IV/Scapa)	Supermarine Scapa
R.24/31		General Purpose Open Sea Patrol Flying Boat	Saunders Roe London, Short R.24/31 Knuckleduster, Supermarine Stranraer
T.23/31		Tiger Moth I production order	de Havilland Tiger Moth I
25/32		Basic trainer - revised-Tutor production order	Avro Tutor I
B.9/32	OR.5	Twin-engine medium day bomber with appreciably higher performance than predecessors - later revised to specify Goshawk power and subsequently re-revised with Goshawk requirement dropped	Vickers Crecy, Handley Page Hampden
B.23/32		Twin-engine medium bomber - written for Heyford I production order	Handley Page Heyford Mk. I
P.27/32		Light day bomber - Hart/Hind replacement - see P.23/35	Armstrong Whitworth A.W.29, Fairey Battle
S.11/32		Naval catapult observation/spotting seaplane for carriage on cruisers	Fairey Seafox
13/33		4-engined mail seaplane and 4-engine flying boat carrier - Short-Mayo Composite	Short S.20 Mercury, Short S.21 Maia
14/33		Fairey Gordon II production order	Fairey Gordon II
21/33		Three-seat general purpose aircraft - improved Vildebeest	Vickers Vincent
24/33		Gloster Gauntlet production order	Gloster Gauntlet
25/33		Twin-engined troop and cargo transport - improved Victoria	Vickers Valentia
B.29/33		Twin engine medium day bomber with power-operated nose turret	Boulton Paul Sidestrand V (Overstrand)
F.5/33		Twin-engine two seat turret fighter - later cancelled	Armstrong Whitworth A.W.34, Boulton Paul P.76, Bristol Type 140, Gloster F.5/33, Parnall F.5/33, Westland-Hill Pterodactyl Mk.V
G.23/33		General purpose aeroplane - Hart for Middle East	Hawker Hardy
R.1/33		Patrol/reconnaissance flying boat	Westland-Hill Pterodactyl Mk.VII
R.2/33		Long-range patrol/reconnaissance flying boat	Short Sunderland
R.3/33		Long-range patrol/reconnaissance flying boat - trials order for Singapore III	Short Singapore III
S.15/33		Naval carrier-borne torpedo bomber/spotter/reconnaissance (TSR) - Fairey 9/30 (q.v.) design modified and re-submitted as T.S.R.II	Blackburn Shark, Fairey Swordfish
T.26/33		Tiger Moth II production order	de Havilland Tiger Moth II
2/34		High-altitude research aircraft capable of reaching 50,000 ft	Bristol Type 138A
16/34		Three-seat general purpose aircraft - Vincent I production order including conversion of outstanding Vildebeests to Vincents	Vickers Vincent I
22/34		Close-support aircraft - Audax for SAAF	Hawker Hartebees
24/34		Basic trainer - production order for second batch of definitive Tutor design - see 3/30, 18/31 & 25/32	Avro Tutor I
30/34		Twin-engined troop and cargo transport - Valentia I production order	Vickers Valentia I
32/34		Navigation trainer - Prefect production order	Avro 626/Prefect
A.39/34		Army Co-operation aircraft	Westland Lysander
B.3/34		Twin-engine night bomber & bomber/transport - Virginia, Heyford & Hendon replacement - transport requirement later removed after protests from manufacturers	Armstrong Whitworth Whitley, Handley Page Harrow
B.20/34		Twin-engine night bomber - Hendon production order to this spec - see also B.19/27	Fairey Hendon
B.23/34		Twin engine medium day bomber - Overstrand production order	Boulton Paul Overstrand
B.28/34		Twin-engine medium bomber - written for Heyford II production order	Handley Page Heyford Mk. II
F.5/34		High-performance fighter with air-cooled engine for overseas (hot climate) use	Bristol 146, Gloster G.38, Martin-Baker M.B.2, Vickers Type 279 Venom
F.36/34 (modified by F.5/34)		Eight-gun fighter with Rolls-Royce PV-12 engine	Supermarine Spitfire, Hawker Hurricane
F.37/34		Eight-gun fighter with Rolls-Royce PV-12 engine capable of 350 mph - see also F.36/34 & F.10/35	Supermarine Spitfire
G.7/34		Interim Hart day bomber replacement	Hawker Hind
O.27/34		Naval dive bomber	Blackburn Skua
P.4/34		Light bomber and close air support aircraft	Fairey P.4/34, Hawker Henley
S.38/34		Written for Swordfish production order	Fairey Swordfish I
2/35		Naval catapult-launched observation/spotting flying boat for carriage on cruisers	Supermarine Walrus
13/35		Naval torpedo-spotter-reconnaissance aircraft - written for Shark production order	Blackburn Shark
14/35		Army Co-operation aircraft - Audax replacement	Hawker Hector
16/35		Autogyro - written for Cierva C.30/Avro 671 Rota evaluation order	Avro Rota
18/35		Twin-engined coastal reconnaissance landplane - written for Anson	Avro Anson
26/35		Naval fighter/reconnaissance - Osprey IV production order	Hawker Osprey IV
36/35		Trans-Atlantic mail plane	de Havilland Albatross
39/35		Twin-engine communications aircraft - Envoy with dorsal turret order for SAAF	Airspeed Envoy
B.1/35	OR.19	Twin-engine medium bomber	Airspeed A.S.29, Armstrong Whitworth A.W.39, Handley Page H.P.55, Vickers Warwick
B.21/35		Twin-engine medium bomber - written for Whitley II production order	Armstrong Whitworth Whitley II
B.27/35		Twin-engine medium bomber - written for Heyford III production order	Handley Page Heyford Mk. III
B.28/35		Drawn up for Bristol 142M	Bristol Blenheim
B.29/35		Written for Harrow intial production order	Handley Page Harrow
F.9/35		Two-seat four-gun turret fighter - Demon replacement	Hawker Hotspur, Boulton Paul Defiant
F.10/35		Drawn up for the Spitfire prototype	Supermarine Spitfire
F.14/35		Written for Gladiator I initial production order	Gloster Gladiator I
F.35/35		Very high speed fighter	Airspeed A.S.31 (not built)
F.37/35	OR.31	Fighter with cannon	Westland Whirlwind, Hawker Hurricane with Oerlikon cannon, Supermarine Type 313
G.24/35		General Reconnaissance - Anson replacement	Bristol Type 149, Bristol Beaufort
M.15/35		Land-based general reconnaissance/torpedo-bomber	Blackburn Botha, Bristol Beaufort
O.30/35		Naval fighter/dive bomber development of Skua (q.v.)	Blackburn Roc
P.23/35		Written for Battle I production order	Fairey Battle I
Q.32/35		Radio-controlled Fleet Gunnery target aircraft - Queen Bee replacement	Airspeed Queen Wasp
10/36		Written for Beaufort production order	Bristol Beaufort I
11/36		Interim General Reconnaissance - aircraft later re-named 'Blenheim IV' and 'Bolingbroke' name transferred to Canadian-built Blenheim	Bristol Bolingbroke I
17/36		Written for Hotspur initial production order - later cancelled	Hawker Hotspur; cancelled
19/36		Naval torpedo-spotter-reconnaissance aircraft - written for Shark additional production order	Blackburn Shark
25/36		Written for Skua initial production order	Blackburn Skua
26/36		Written for Roc initial production order	Blackburn Roc
29/36		Written for Wellington (revised Crecy from B.9/32) initial production order	Vickers Wellington I
33/36		Written for Blenheim I production order (Rootes)	Bristol Blenheim I
36/36		Written for Lysander initial production order	Westland Lysander I
37/36		Written for Walrus additional production order	Supermarine Walrus I
42/36		Target tug - order for Henley target tug conversions by Gloster's	Hawker Henley III
47/36		Written for Bombay II production order	Bristol Bombay II
B.12/36	OR.40	Four-engine heavy bomber	Armstrong Whitworth B.12/36, Short Stirling, Supermarine Type 316
B.20/36		Twin-engine medium bomber - written for Whitley III production order	Armstrong Whitworth Whitley III
B.30/36		Written for Hampden initial production order	Handley Page Hampden I
B.44/36		Written for Dagger-Hampden (Hereford) production order	Handley Page Hereford I
R.1/36	OR.32	Small reconnaissance flying boat	Saro Lerwick, Blackburn B-20
P.13/36	OR.41	Twin Vulture-engined medium bomber for "world-wide use" - introduction delayed due to production difficulties necessitating further order of Whitleys & Wellingtons	Avro Manchester, Handley Page H.P.56, Vickers Warwick with Rolls-Royce Vulture engines.
S.41/36		Naval carrier-borne torpedo bomber - Swordfish replacement	Fairey Albacore
T.6/36		Advanced monoplane trainer mounting manually-operated dorsal turret - Don accepted but proved unsuitable	de Havilland Don, Miles Kestrel
T.23/36		Multi-role crew trainer	Airspeed Oxford
T.40/36	OR.44	Development and production of a trainer version of the Miles Hawk	Miles Magister
2/37		Written for Blenheim I production order (Avro)	Bristol Blenheim I
6/37		Twin-engine VIP transport aircraft - order for The King's Flight	Airspeed Envoy
19/37		Written for Manchester I production order	Avro Manchester I
20/37		Written for Roc floatplane production order	Blackburn Roc
32/37		Written for Halifax initial production order	Handley Page Halifax I Srs 1 - I Srs 3
37/37		Magister I production order	Miles Magister I
38/37		Three-seat communications aircraft & instrument/wireless trainer	Miles Mentor
43/37		Engine testbed	Folland Fo.108; designs also tendered by General Aircraft & Percival
B.32/37	OR.44	Production contract for a four-engine version of the P.13/36 H.P.56 design	Handley Page H.P.57 Halifax
F.9/37	OR.49	Twin-engine day/night fighter	Gloster G.39
F.11/37		Twin-engine two seat day & night fighter/ground support	Boulton Paul P.92
F.18/37		Heavily armed interceptor armed with 12 x 0.303 mgs and capable of at least 400 mph	Bristol F.18/37, Gloster F.18/37, Hawker Tornado, Hawker Typhoon, Supermarine Type 324, Supermarine Type 325
Q.8/37		Radio-controlled Fleet Gunnery target aircraft - Queen Bee replacement - role subsequently carried-on by Queen Wasp - see Q.32/35	Airspeed A.S.37 (not built)
S.23/37	OR.52	Four-engine carrier-based Fleet shadower/follower - low-speed, high-endurance, ship-tracking aircraft - requirement later rendered obsolete due to introduction of radar	Airspeed AS.39, General Aircraft GAL.38
S.24/37	OR.53	Naval torpedo/dive-bomber, reconnaissance - Supermarine entry featured variable-incidence wing	Supermarine S.24/37, Fairey Barracuda
T.1/37		Basic trainer	Heston T.1/37 Trainer, Miles M.15, Parnall 382/Heck 3, Airspeed A.S.36 (not built)
16/38		Trainer - Master I production order	Miles Master T.Mk.I
20/38		Communications aircraft - Vega Gull order	Percival Vega Gull
21/38		Communications aircraft - Dominie production order	de Havilland Dominie
24/38		Twin-engine communications aircraft - Envoy production order	Airspeed Envoy
25/38		Twin-engine communications aircraft	Percival Petrel
26/38	OR.65	Three-seat wireless or navigation training aircraft with dual controls - Vega Gull adapted for communications training	Percival Proctor I
28/38	OR.66	Two-seat helicopter - written for Weir W.6	Weir W.6
B.9/38		Twin-engine medium bomber of simple construction using materials other than light alloy wherever possible	see B.18/38
B.18/38		Twin-engine medium bomber of mixed wood/metal construction	Armstrong Whitworth Albemarle
O.8/38		Naval carrier-borne fighter/observation - winner developed from Fairey's earlier P.4/34 entry	Fairey Fulmar
S.7/38		Naval catapult-launched observation/spotting flying boat - Walrus replacement	Supermarine Sea Otter
T.29/38		Twin-engine R/T (Radio Telephony) training aircraft - Dominie three aircraft order	de Havilland Dominie
19/39		Twin-engine transport aircraft - order for Hertfordshire later cancelled	de Havilland Hertfordshire
20/39		Twin-engine communications aircraft - order for No. XXIV Squadron RAF	de Havilland Flamingo
21/39		Twin-engine VIP transport aircraft - order for The King's Flight	de Havilland Flamingo
B.1/39		Four-engined heavy bomber	Avro Lancaster, Handley Page H.P.60, Short S.34
B.23/39		Very high altitude version of Wellington capable of operating at 40,000 ft	Vickers Wellington V
E.28/39		Experimental aircraft using Whittle jet-propulsion with provision for 4 x 0.303 machine guns	Gloster E.28/39
F.17/39		Long-range fighter development of Bristol Beaufort - written for Beaufighter	Bristol Beaufighter
F.18/39		Fighter - Hurricane/Spitfire replacement	Martin-Baker M.B.3, Martin-Baker M.B.5
F.22/39	OR.76	Fighter fitted with heavy-calibre nose-mounted gun	Vickers 414 Vickers Type 432 - also tests with Vickers Type 439 testbed - specification later cancelled
N.8/39		Naval two-seat carrier-borne fighter - Roc replacement - replaced by N.11/40	see N.11/40
N.9/39		Naval two-seat carrier-borne fighter - Fulmar replacement - replaced by N.11/40	see N.11/40
R.5/39		Long-range patrol flying boat - Sunderland replacement - superseded by R.14/40 (q.v.)	Saunders-Roe S.38 - later cancelled
T.34/39		Advanced trainer	Airspeed Cambridge - later cancelled

1940-1949

Spec.	OR	Type	Designs (accepted and tendered)
17/40		Very high altitude bomber - Wellington V production order	Vickers Wellington V
B.1/40	OR.78	Twin-engine fast bomber carrying no defensive armament	de Havilland Mosquito
B.6/40		Twin-engine day/close support bomber - later renamed Blenheim V	Bristol Bisley
B.20/40		"Close Army Support Bomber" with Merlin engine able to dive bomb and photo-reconnaissance	De-navalised version of Fairey Barracuda offered but specification not proceeded with.[2]
E.28/40		Experimental research aircraft for deck landings - cancelled 1943	Folland Fo.116 (not built)
F.2/40		Fighter using Whittle jet-propulsion (Metrovick) - written for Meteor - see also F.9/40	Gloster Meteor II
F.4/40		High-altitude fighter - superseded by F.7/41 (q.v.)	Westland Welkin
F.9/40		Fighter using Whittle jet-propulsion (Rover/Rolls-Royce) - written for Meteor - see also F.2/40	Gloster Meteor I
F.16/40		High-altitude fighter	Vickers Type 432
F.18/40		Night fighter version of Mosquito	de Havilland Mosquito NF.II
F.19/40		Low-cost emergency production fighter	Miles M.20
F.21/40		Fighter version of Mosquito	de Havilland Mosquito F.II
N.5/40		Naval 2-seat Fleet fighter	Fairey Firefly
N.11/40		Naval Fighter	Blackburn Firebrand F.1
R.14/40	OR.91	Very long range reconnaissance flying boat - Centaurus-engined Sunderland replacement	Saunders-Roe S.41, Short Shetland
S.12/40		Naval catapult-launched observation/spotting flying boat - Walrus & Sea Otter replacement - superseded by S.14/44 (q.v.)	Supermarine Type 381
T.24/40		Training aircraft	Airspeed A.S.50 (not built)
X.10/40		Troop-carrying glider capable of carrying 7 troops	General Aircraft Hotspur I; cancelled after eighteen built - redesigned Hotspur II relegated to training - see X.22/40 & X.23/40
X.22/40		Troop-carrying training glider - Hotspur II production order	General Aircraft Hotspur II
X.23/40		Troop-carrying training glider - Hotspur II further production order	General Aircraft Hotspur II
X.25/40	OR.98	Troop-carrying glider capable of carrying 14 troops	Slingsby Hengist
X.26/40		Troop-carrying glider of wooden construction capable of carrying between 24-36 fully armed troops	Airspeed Horsa
X.27/40		Tank-carrying heavy glider capable of carrying 7-ton load	General Aircraft Hamilcar
12/41		Target tug	Miles Martinet
B.2/41		Twin-engine bomber - Blenheim replacement - requirement exceeded by Mosquito and Buckingham relegated to courier/transport duties	Bristol Buckingham C.1
B.5/41	OR.106	Pressurised high-altitude bomber - evolved into B.3/42 (q.v.)	Pressurised version of the Vickers Warwick III
B.8/41		Four-engined heavy bomber - see also B.3/42	Short S.36, ''Vickers Windsor
B.11/41		High-speed high-altitude unarmed bomber	de Havilland DH.99, Hawker P.1005, Miles M.39
E.6/41		Experimental jet fighter - DH Spider Crab	de Havilland Vampire
F.4/41		Spitfire with Griffon engine - written for Spitfire IV but amended to include Mk. XXI redesign. Preceded in introduction by Mk.s XII & XIV - some overlap with F.1/43 (q.v.)	Supermarine Spitfire XXI
F.7/41	OR.108	High-altitude fighter - revised from F.4/40 (q.v.)	Vickers Type 432, Westland Welkin
F.10/41		Written for Hawker Tempest	Hawker Tempest
N.1/41		Naval fighter	Miles M.20/4
T.9/41		Four-seat radio trainer.	Percival Proctor IV
X.3/41		Emergency Tallboy-carrying conversion of Horsa for attack on Tirpitz - later cancelled when Lancaster was modified to carry Tallboy	Airspeed A.S.52 Horsa
5/42		Glider for RAAF	de Havilland Australia DHA.G2
B.3/42	OR.115	High-performance long-range bomber	Vickers Windsor
C.1/42		Cargo version of Lancaster - York I production order	Avro York I
E.5/42		Experimental single-engined jet fighter - later cancelled - see E.1/44	Gloster GA.1
E.6/42		Experimental lightweight Tempest - written for Tempest Light Fighter - refined & re-issued as F.2/43 (q.v.)	Hawker Fury - see F.2/43
F.6/42		Single-seat fighter	Boulton Paul P.99, Boulton Paul P.100, Hawker Type P.1018, Hawker Type P.1019, Hawker Type P.1020, Folland Fo.117a, Miles M.42, Miles M.43, Miles M.44
H.7/42		Torpedo bomber - Beaufighter replacement	Bristol Brigand
Q.9/42		Twin engine target tug - planned production of Monitor later cancelled - see also Q.1/46	'Miles Monitor TT Mk.1
R.8/42	OR.118	Long-range patrol/reconnaissance flying boat - Sunderland with Hercules engines	Short Sunderland IV/Seaford
20/43	OR.142	Two-seat training glider suitable for ATC cadets	Slingsby Kirby Cadet TX Mk.1
29/43		Airliner version of Lancaster IV - see also B.14/43	Avro Tudor
A.17/43		Army liaison and VIP transport aircraft - Messenger I production order	Miles Messenger I
B.14/43		Heavy bomber	Avro Lincoln, Handley Page H.P.65
B.27/43		Heavy bomber - bomber version of Hastings	Handley Page H.P.66/Hastings B.1
E.16/43		Experimental helicopter	Cierva W.9
E.24/43		Experimental jet research aircraft capable of 1,000 mph and able to reach 36,000 ft in 1 and 1/2 minutes	Miles M.52; cancelled 1946
F.1/43	OR.120	Development of Spitfire with Griffon & laminar flow wing - see also N.5/45	Supermarine Spiteful
F.2/43		Written for Tempest Light Fighter	Hawker Fury; cancelled at conclusion of hostilities.
F.9/43		Two-seat high-altitude night fighter	Westland Welkin NF.II
F.12/43		Long-range fighter for Pacific - written for Hornet	de Havilland Hornet
F.19/23			Folland design to be built by English Electric
N.4/43	OR.113	Carrier-based fighter - Seafire with Griffon engine	Supermarine Seafire XV
N.7/43		Carrier-based fighter - revised as N.22/43 (q.v.)	Hawker Sea Fury
N.22/43		Revision of N.7/43; carrier-based fighter	Hawker Sea Fury
O.5/43		Torpedo bomber - Barracuda replacement	Fairey Spearfish
Q.10/43		Radio-controlled Fleet Gunnery target aircraft - Queen Wasp replacement	Miles Queen Martinet
S.11/43		Naval carrier-borne attack/strike aircraft - later cancelled - Sturgeon also submitted to Q.1/46 & M.6/49 (q.v.)	Armstrong Whitworth A.W.54, Short Sturgeon
S.28/43		Firebrand replacement	Blackburn B-48 YA.1/Firecrest
T.13/43		Advanced trainer	Bristol Buckmaster
T.23/43		Trainer - all-weather fully aerobatic three-seater	Percival Prentice
TX.3/43		Two-seat side-by-side seating training glider	General Aircraft G.A.L.55
2/44	Brabazon Committee Type I	Long range transatlantic airliner	Bristol Brabazon I, Miles X-15 (not built)
16/44		Stop-gap airliner version of Lancaster	Avro Lancastrian C.Mk 1
18/44	Brabazon Committee Type Va	Civil feederliner	Miles Marathon
22/44		Transport aircraft - mixed passenger, freight/passenger or all-freight high-payload/short-distance - see also G.9/45	Bristol Wayfarer/Freighter
C.3/44		Long-range general-purpose transport - York replacement	Handley Page Hastings
E.1/44		Experimental Nene-powered jet fighter	Gloster GA.2
E.6/44		Written for Saro SR.44 flying-boat jet fighter	Saro SR.A/1
E.9/44		Flying wing bomber/airliner	Armstrong Whitworth A.W.52
E.10/44		Experimental Nene-powered jet fighter - Jet Spiteful	see N.5/45
F.13/44		Long-range fighter with Eagle 22 piston engine capable of accepting a turboprop at a later date - RAF version of N.11/44 (q.v.) - see also N.12/45	Westland Wyvern
N.5/44		Naval carrier-version of Hornet	de Havilland Sea Hornet
N.7/44	OR.167	Carrier-based fighter - navalised version of Spitfire F Mk.21	Supermarine Seafire F Mk.45
N.11/44		Naval long-range carrier-based fighter with Eagle 22 piston engine capable of accepting a turboprop at a later date - RN version of F.13/44 (q.v.) - see also N.12/45	Westland Wyvern
N.15/44		Naval carrier-version of Mosquito	de Havilland Sea Mosquito TR.33
S.14/44		Naval land-based ASR	Supermarine Seagull ASR-1
X.4/44		Tank-carrying heavy glider capable of carrying 7-ton load and returning under its own power	General Aircraft Hamilcar X
A.2/45		Army Aerial Observation Post (AOP) - replacement for Taylorcraft Auster AOPs	Auster A.2/45, Heston A.2/45
A.4/45		Army three-seat light communications aircraft - Leonides-powered Pioneer II later accepted 1950	Scottish Aviation Pioneer I
B.3/45		Two-seat twin-engine high-altitude fast jet bomber carrying no defensive armament - Mosquito replacement - revised from E.3/45 (q.v.)	English Electric Canberra B.1 - see also B.5/47
C.15/45		Transport aircraft	Handley Page H.P.72
E.1/45	OR.207	Experimental aircraft for research into proposed tailless configuration of early DH.106 Comet airliner design	de Havilland DH.108
E.3/45		Experimental two-seat twin-engine high-altitude fast jet bomber carrying no defensive armament - Mosquito replacement - reissued as B.3/45 (q.v.)	English Electric Canberra
E.11/45		Experimental aircraft for research into low-speed handling and high Mach number flying of tailless designs - two examples of Swallow (one low- and one high-speed) ordered - see also E.1/45	de Havilland DH.108
N.5/45		Naval carrier-borne fighter - Seafang developed to this spec. but supplanted by Nene-powered, Naval version of E.10/44 (q.v.)	Supermarine Attacker, Supermarine Seafang
N.12/45		Long-range carrier-based fighter - Wyvern with Python turboprop engine - see also F.13/44 & N.11/44	Westland Wyvern S.4
G.9/45		Military transport aircraft capable of carrying a 3 ton load into jungle areas - see also 22/44	Bristol Wayfarer/Freighter
GR.17/45	OR.220	Carrier-borne ASW	Blackburn B-54/B-88, Fairey Gannet
Q.19/45	OR.204	Mosquito target tug	de Havilland Mosquito TT.39
T.7/45		Three-seat advanced trainer using turboprop engine - Harvard replacement - replaced by T.14/47 (q.v.)	Avro Athena T.1, Boulton Paul Balliol T.1
2/46	Brabazon Committee Type I	Long range transatlantic airliner - Brabazon II (Coupled Proteus) order	Bristol Brabazon II
26/46	Brabazon Committee Type II	Short-range feederliner - Dragon Rapide replacement	de Havilland Dove
B.14/46	OR.239	Four engine jet heavy bomber - later used as insurance against delay of aircraft submitted to B.35/46	Short Sperrin
B.35/46	OR.229	Four engine swept-wing jet heavy bomber with a cruising speed of 500 kt and a ceiling of at least 55,000 ft	Armstrong Whitworth A.W.56, Avro Vulcan, Bristol Type 172, Handley Page Victor, Short PD.1; Designs also submitted by Vickers & English Electric
C.16/46	Brabazon Committee Type IIB	Short-medium range airliner	Armstrong Whitworth A.W.55 Apollo, Handley Page H.P.76, Handley Page H.P.77, Handley Page H.P.78, Vickers Viscount
E.4/46		Experimental gyrodyne	Fairey Gyrodyne
E.19/46		Experimental helicopter for crop spraying	Cierva Air Horse
E.27/46		Experimental aircraft for investigation into delta wing characteristics at transonic speeds	Boulton Paul P.111
E.41/46		Experimental swept-wing version of Attacker - evolved into Swift	Supermarine 510, Supermarine Swift
F.43/46		Interceptor using Rolls-Royce AJ.65 or Metrovick F.9 axial engines - superseded by F.3/48 (q.v.)	Gloster P.234, Gloster P.248, Gloster P.250, Hawker P.1054
F.44/46		Two-seat twin-engined night/all weather fighter	see F.24/48 & F.4/48
N.7/46		Naval carrier-borne interceptor/fighter bomber	Hawker Sea Hawk
N.11/46		Two seat trainer version of Sea Fury	Hawker Sea Fury T.20
N.40/46		Naval carrier-borne jet fighter - see also F.4/48	de Havilland DH.110
R.5/46		Four engine long-range Maritime patrol bomber - Liberator GR replacement	Avro Shackleton
Q.1/46		Naval target tug	de Havilland Mosquito TT.39, Miles Monitor, Short Sturgeon TT.1,
B.5/47	OR.235	Three-seat twin-engine high-altitude fast jet bomber carrying no defensive armament - Mosquito replacement - revised from B.3/45 (q.v.) to include visual bombing requirement	English Electric Canberra B.2
C.2/47	Brabazon Committee Type III	Airliner - medium-range Empire transport	Bristol Britannia, Handley Page H.P.83, Handley Page H.P.84, Handley Page H.P.85, Handley Page H.P.86
E.8/47	OR.250	Experimental one-half scale research version of Bristol Type 172 four-jet long range bomber design - later revised for reconfigured Type 176 - all subsequently cancelled	Bristol Type 174
N.9/47		Naval carrier-borne jet fighter	Supermarine Type 508
T.1/47		Two seat trainer version of Meteor - written around Gloster's civil Meteor demonstrator G-AKPK	Gloster Meteor T.7
T.14/47		Two-seat advanced trainer using Merlin 35 - replacement for T.7/45 (q.v.)	Avro Athena T.2, Boulton Paul Balliol T.2
8/48		ab initio trainer - Tiger Moth replacement - written for Chipmunk T.10 production order	de Havilland Chipmunk T.10
E.6/48	no OR	Experimental research aircraft using one-third scale version of Handley Page B.35/46 wing design	'''Handley Page HP.88
E.15/48	no OR	Experimental one-third scale low-speed research version of Avro's B.35/46 design	'''Avro 707
F.3/48	OR.228	Written for P.1067, replaced F.43/46	Hawker P.1067 (Hawker Hunter)
F.4/48	OR.227	Two-seat twin-engined night/all weather fighter - replacement for Vampire NFs	de Havilland DH.110, Gloster Javelin
F.24/48		Two-seat twin-engined night/all weather fighter - interim stop-gap for F.4/48 - Meteor NF development originally to F.44/46 (q.v.)	Armstrong Whitworth Meteor NF.11
B.9/48	OR.231	Four engine jet heavy bomber - less advanced stop-gap for B.35/46 designs - written around Valiant	Vickers Valiant
B.22/48	OR.302	Pathfinder version of Canberra	English Electric Canberra B.5
R.2/48	OR.231
T.12/48		Trainer - two-seat Wyvern conversion trainer	Westland Wyvern T.3
T.16/48		Trainer - Prentice replacement	Handley Page H.P.R.2, Percival Provost
C.19/49		Transport - Hastings C.2 order	Handley Page Hastings C.2
E.10/49		Experimental - additional order for Avro 707s including side-by-side seating conversion-trainers - these later cancelled - see also E.15/48	'''Avro 707
F.15/49		Jet fighter - interim Vampire replacement	de Havilland Venom
F.23/49	OR.268	Supersonic jet fighter/interceptor	English Electric Lightning
M.6/49	OR.275	Light carrier-borne ASW - written around Short Sturgeon variant - spec derived from GR.17/45	Short S.B.3
N.14/49		Naval carrier-borne all-weather strike fighter - see also N.40/46 & F.4/48	de Havilland Sea Vixen
E.27/49		Delta wing research	Boulton Paul P.120

Post 1949 Operational Requirements and Naval Requirements

OR	Year	Type	Related aircraft
ER.100	194?	Experimental low-speed research version of English Electric P.1 (q.v.)	Short S.B.5
ER.103	1947	Experimental research aircraft capable of Mach 1.5 at 36,000 ft - modified for P.1 as F.23/49 (q.v.)	English Electric P.1, Fairey Delta 2
OR.301	February 1952	Rocket propelled interceptor	Saunders Roe SR.53, Avro 720
OR.303	195?	Lightweight fighter to intercept Soviet Tu-4 bombers	Folland Midge
OR.304	195?	Helicopter for Coastal Command	Bristol Sycamore
OR.323	195?	Transport aircraft - Hastings replacement	Armstrong Whitworth Argosy
OR.324	1952	Low-level bomber - Spec. B.126T written to this OR - cancelled 1954	Avro 721, Handley Page H.P.99 - proposals also tendered by: Bristol, Shorts & Vickers.
OR.334	195?	VTOL transport aircraft	Fairey Rotodyne; later cancelled
ER.43	~1953	Experimental direct jet-lift VTOL research aircraft	Short SC.1
ER.134	1953	Experimental high-speed research aircraft capable of sustaining Mach 2.75 to investigate effect of kinetic heating on airframe	Bristol 188
ER.163	195?	Experimental Fairey Delta 2 with de Havilland Gyron engine - later cancelled	Fairey Delta 2
ER.204D	195?	Experimental VTOL aircraft using Bristol Pegasus	Hawker P.1127
NA.39	1953	Carrier borne strike aircraft to Spec. M.148T	Blackburn Buccaneer, Short PD.13
NA.47	195?	Mixed rocket-jet interception fighter for RN	Saunders-Roe SR.177; cancelled 1957
NR/A.32	195?	Light carrier-borne ASW to Spec. M.123	Short Seamew
F138D	1953	Mixed rocket-jet interception fighter - written around SR.53	Saunders-Roe SR.53
OR.330	1954	Supersonic high flying reconnaissance aircraft	Avro 730, Handley Page H.P.100
OR.329 /F.155	1955?	Supersonic high flying interceptor	Fairey "Delta III"; cancelled 1957
OR.356	19??	Supersonic V/STOL - Spec. SR.250	Hawker Siddeley P.1154; later cancelled
OR.357	19??	Maritime reconnaissance aircraft - led to Nimrod	Hawker Siddeley Nimrod
OR.362	19??	Supersonic trainer aircraft - led to Jaguar	SEPECAT Jaguar
GOR.339	1956	STOL Tactical-Strike/Reconnaissance aircraft capable of Mach 2 and suitable for operation from unpaved strips - Canberra replacement	British Aircraft Corporation TSR-2; later cancelled
GOR.345	195?	V/STOL combat aircraft version of Hawker P.1127 - Harrier development	Hawker Siddeley Harrier
GSR.3335	196?	Helicopter - Scout replacement	Westland Lynx
GSR.3336	196?	Helicopter - Sioux replacement	Westland Gazelle
RB.156		Reconnaissance-bomber	Avro 730
ASR.365	196?	Helicopter - Tactical Support	Westland Puma
ASR.367	196?	Bomber - Vulcan B.2 - see also B.35/46	Avro Vulcan B.2
ASR.368	196?	Bomber - Victor B.2 - see also B.35/46	Handley Page Victor B.2
ASR.371	196?	Transport aircraft	Short Belfast
ASR.372	196?	Trainer version of Lightning - Lightning T.5	English Electric Lightning T.5
ASR.373	196?	VIP Transport aircraft - Andover CC.2	Hawker Siddeley Andover CC.2
ASR.376	196?	Tanker aircraft	Handley Page Victor B(K).1/1A
ASR.378	196?	Transport aircraft - VC10	Vickers VC10
ASR.381	196?	Interim Maritime Patrol aircraft to Spec. MR.254 - written around Atlantique	Breguet Atlantique
ASR.382	196?	Two-seat trainer version of P.1154 for RAF - cancelled	Hawker Siddeley P.1154
ASR.384	196?	Harrier requirement - see also GOR.345	Hawker Siddeley Harrier
ASR.385	196?	Phantom for RAF	McDonnell Douglas F-4M Phantom
ASR.397	1970	Basic jet trainer - Jet Provost replacement	Hawker Siddeley Hawk
ASR.409		Harrier replacement	McDonnell Douglas AV-8 as Harrier GR.5
NSR.6451	19??	V/STOL carrier borne fighter aircraft - Naval Harrier	BAE Sea Harrier

See also

• British military aircraft designation systems
• General Staff Target - the British Army equivalent

References

• Aeroplane Monthly Magazine. - various articles - various issues 1973-1987. Web site
• Buttler, Tony. Secret Projects: British Fighters and Bombers 1935 -1950 (British Secret Projects 3). Leicester, UK: Midland Publishing, 2004. ISBN 1-85780-179-2.
• Green, William. Famous Bombers of the Second World War, 2nd Edition. London: MacDonald & Jane's,1975. ISBN 0-356-08333-0.
• Meekcoms, K.J. and Morgan, E.B. The British Aircraft Specifications File. London: Air Britain, 1994. ISBN 0-85130-220-3.
• Munson , Kenneth. Bombers Between the Wars 1919-39 - Including Patrol and Transport Aircraft (Blandford Colour Series). London: Associate R.Ae.S., 1970. ISBN 0-7137-0514-0.
• Munson , Kenneth. Bombers In Service - Patrol and Transport Aircraft Since 1960 (Blandford Colour Series). London: Associate R.Ae.S., 1972. ISBN 0-7137-0586-8.
• Munson , Kenneth. Fighters 1939-45 - Attack and Training Aircraft (Blandford Colour Series). London: Associate R.Ae.S., 1975. ISBN 0-7137-0378-4.
• Munson , Kenneth. The Pocket Encyclopedia of Bombers At War (Blandford Colour Series, New Orchard Edition). London: Associate R.Ae.S., 1977. ISBN 0-18507-902-8.

Note: This is a combined volume made up of the following separate books:

: Munson, Kenneth.Bombers Patrol and Reconnaissance Aircraft 1914-1919 (Blandford Colour Series) . London: Associate R.Ae.S., 1977. ISBN 0-7137-0632-8.

: Munson, Kenneth. Bombers Patrol and Transport Aircraft 1939-1945 (Blandford Colour Series) , London: Associate R.Ae.S., 1975. ISBN 0-7137-0379-2.

• Sinnott, Colin. The RAF and Aircraft Design, 1923-1939: Air Staff Operational Requirements London: Frank Cass, 2001. ISBN 0-7146-5158-3.

External links

• Handley Page Aircraft
• United Kingdom Aerospace and Weapons Projects- Post War Operational Requirements
• Unusual Aircraft - British Projects
• WW2 British Secret Projects Vol. 1