List of Air Ministry specifications
1940–1949

List of Air Ministry specifications

Section Title: 1940–1949
Table Section Text: None

Spec	OR	Type	Designs

B.1/40	OR.78	Twin-engine fast bomber carrying no defensive armament	de Havilland Mosquito

F.1/40	Air Observation Post (AOP)	Fane F.1/40, General Aircraft GAL.47

2/40	OR.79	Twin-engined trainer aircraft	Caproni Ca 311, Caproni Ca 313

F.2/40	Fighter using Whittle jet-propulsion (Metrovick) – written for Meteor – see also F.9/40	Gloster Meteor II

B.3/40	OR.80	High speed bomber	Blackburn B.28[page needed]

F.4/40	OR.81	High-altitude fighter – superseded by F.7/41 (q.v.)	Westland Welkin

N.5/40	OR.82	Naval 2-seat Fleet fighter	Fairey Firefly

B.6/40	OR.83	Twin-engine day/close support bomber – later renamed Blenheim V	Bristol Bisley

B.7/40	OR.84	Medium Bomber replacement for Blenheim bomber development of Beaufighter	A design by Armstrong Whitworth not taken further Bristol Beaumont accepted but not built, led to Buckingham (q.v.)

8/40	OR.85	Ambulance Aircraft	Airspeed Oxford

F.9/40	OR.86	Fighter using Whittle jet-propulsion (Rover/Rolls-Royce) – written for Meteor – see also F.2/40	Gloster Meteor I

X.10/40	OR.87	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

N.11/40	OR.88	Naval single-seat Fleet fighter powered by Napier Sabre – see also S.8/43	Blackburn Firebrand F.I, Hawker P.1009 "Fleet Fighter"

S.12/40	OR.89	Naval catapult-launched observation/spotting flying boat – Walrus & Sea Otter replacement – superseded by S.14/44 (q.v.)	Supermarine Type 381

R.13/40	OR.90	General-purpose flying boat	Blackburn B-40

R.14/40	OR.91	Very long range reconnaissance flying boat – Centaurus-engined Sunderland replacement	Saunders-Roe S.41, Short Shetland

15/40	OR.92	Conversion of Supermarine Spitfire for Photographic Development Unit	Supermarine Spitfire

F.16/40	High-altitude fighter	Vickers Type 432

17/40	OR.94	Very high altitude bomber – Wellington V production order	Vickers Wellington V

F.18/40	OR.95	Night fighter with turret	Gloster F.18/40, fulfilled by de Havilland Mosquito NF.II

F.19/40	Low-cost emergency production fighter	Miles M.20/2

B.20/40	"Close Army Support Bomber" with Merlin engine able to dive bomb and photoreconnaissance	De-navalised version of Fairey Barracuda offered but specification not proceeded with.[page needed]

F.21/40	OR.96	Fighter version of Mosquito	de Havilland Mosquito F.II

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

T.24/40	Training aircraft	Airspeed A.S.50 (not built)

X.25/40	OR.98	Troop-carrying glider capable of carrying 14 troops	Slingsby Hengist

X.26/40	OR.99	Troop-carrying glider of wooden construction capable of carrying between 24-36 fully armed troops	Airspeed Horsa

X.27/40	OR.100	Tank-carrying heavy glider capable of carrying 7-ton load	General Aircraft Hamilcar

E.28/40	OR.101	Experimental research aircraft for deck landings - cancelled 1943	Folland Fo.115, Folland Fo.116 (ordered but not completed)

F.29/40	Twin-engined night fighter	to cover the Gloster "Reaper" development of F.9/37 (cancelled May 1941)

N.1/41	OR.102	Naval fighter	Miles M.20/4

B.2/41	Twin-engine bomber - Blenheim replacement - written for redesigned Bristol Type 162 Beaumont. Changes in requirements and availability of superior aircraft led to type no longer being needed	Bristol Buckingham (adapted for courier duties as C.1)

X.3/41	OR.104	Emergency Tallboy-carrying conversion of Horsa for attack on Tirpitz - later cancelled when Lancaster was modified to carry Tallboy	Airspeed A.S.52 Horsa

F.4/41	Spitfire with Griffon engine - written for Spitfire IV but amended to include Mk. XXI redesign.	Supermarine Spitfire XXI

B.5/41	OR.106	Pressurised high-altitude bomber - evolved into B.3/42 (q.v.)	Pressurised version of the Vickers Warwick III

E.6/41	OR.107	Experimental jet fighter - DH Spider Crab	de Havilland Vampire

F.7/41	OR.108	High-altitude fighter - revised from F.4/40 (q.v.)	Vickers Type 432, Westland Welkin

B.8/41	Four-engined heavy bomber - see also B.3/42	Short S.36, Vickers Windsor

T.9/41	Four-seat radio trainer.	Percival Proctor IV

F.10/41	OR.109	Written for Hawker Tempest a.k.a. "Thin-Wing Typhoon"	Hawker Tempest

B.11/41	OR.110	High-speed high-altitude unarmed bomber	de Havilland DH.99, Hawker P.1005, Miles M.39

12/41	Target tug	Miles Martinet

C.1/42	OR.113	Interim transport aircraft - cargo version of Lancaster - York I production order	Avro York I

N.2/42	OR.114	Single-seat boat fighter	Blackburn B-44

B.3/42	OR.115	High-performance long-range bomber	Vickers Windsor

B.4/42	High performance bomber (Mosquito replacement) - Cancelled

5/42	Glider for RAAF	De Havilland Australia DHA-G2

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	OR.117	Torpedo bomber - Beaufighter replacement	Bristol Brigand

R.8/42	OR.118	Long-range patrol/reconnaissance flying boat - Sunderland with Hercules engines	Short Sunderland IV/Seaford

Q.9/42	OR.119	Twin engine target tug - planned production of Monitor later cancelled - see also Q.1/46	'Miles Monitor TT Mk.1

10/42	"Special Rotating Wing Glider"	used to identify the Hafner Rotabuggy

B.27/42	Halifax development aircraft	Handley Page Halifax

F.1/43	OR.120	Development of Spitfire with Griffon & laminar flow wing - see also N.5/45	Supermarine Spiteful

F.2/43	OR.121	Written for Tempest Light Fighter	Hawker Fury; cancelled at conclusion of hostilities.

TX.3/43	OR.122	Two-seat side-by-side seating training glider	General Aircraft G.A.L.55

N.4/43	OR.113	Carrier-based fighter - Seafire with Griffon engine	Supermarine Seafire XV

O.5/43	OR.144	Torpedo bomber - Barracuda replacement	Fairey Spearfish

S.6/43	Torpedo Bomber Reconnaissance Aircraft (Cancelled)	Armstrong Whitworth A.W.53

N.7/43	Carrier-based fighter - revised as N.22/43 (q.v.)	Hawker Sea Fury

S.8/43	OR.124	Naval single-seat Fleet fighter capable of carrying rockets, torpedo or bombs - Firebrand powered by Centaurus - see also N.11/40	Blackburn Firebrand TF.III

F.9/43	OR.125	Two-seat high-altitude night fighter	Westland Welkin NF.II

Q.10/43	Radio-controlled Fleet Gunnery target aircraft - Queen Wasp replacement	Miles Queen Martinet

S.11/43	OR.146	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

F.12/43	OR.126	Long-range fighter for Far East - written for Hornet	de Havilland Hornet

T.13/43	OR.148	Advanced trainer	Bristol Buckmaster

B.14/43	Heavy bomber for Far East	Avro Lincoln, Handley Page H.P.65

15/43	OR.151	Medium Range Civil Transport Aircraft	Handley Page Hermes

E.16/43	Experimental helicopter with powered tilting hub controlled rotor with automatic collective pitch control, and torque reaction control using jet efflux.	Cierva W.9

A.17/43	OR.145	Army liaison and VIP transport aircraft - Messenger I production order	Miles Messenger I

C.18/43	Stop-gap airliner version of Stirling	Short S.37 Stirling

F.19/43	OR.127	Folland design to be built by English Electric

20/43	OR.142	Two-seat training glider suitable for ATC cadets	Slingsby Kirby Cadet TX Mk.1

T.21/43	OR.153	Trainer version of Fairey Spearfish	Fairey Spearfish T. Mk 1

N.22/43	OR.155	Revision of N.7/43; carrier-based fighter	Hawker Sea Fury

T.23/43	OR.131	Trainer – all-weather fully aerobatic three-seater	Percival Prentice

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

25/43	Brabazon IIA – Civil Transport for European service	Airspeed Ambassador

C.26/43 (26/43)	Brabazon VB – Light Civil Air Transport	De Havilland Dove

B.27/43	OR.149	Heavy bomber – developed Halifax	Handley Page HP.66 and HP.69 – cancelled with end of war.

S.28/43	OR.150	Firebrand replacement	Blackburn B-48 YA.1/Firecrest

29/43	Airliner version of Lancaster IV - see also B.14/43	Avro Tudor

E.1/44	OR.157	Experimental Nene-powered jet fighter	Gloster GA.2

2/44	Brabazon Committee Type I	Long range transatlantic airliner	Bristol Brabazon I, Miles X-11 (not built)

C.3/44	Long-range general-purpose transport - York replacement	Handley Page Hastings

X.4/44	OR.160	Tank-carrying heavy glider capable of carrying 7-ton load and returning under its own power	General Aircraft Hamilcar X

N.5/44	OR.162	Naval carrier-version of Hornet	de Havilland Sea Hornet

E.6/44	OR.170	Written for Saro SR.44 flying-boat jet fighter	Saro SR.A/1

N.7/44	OR.167	Carrier-based fighter - navalised version of Spitfire F Mk.21	Supermarine Seafire F Mk.45

PR.8/44	Photoreconnaissance version of the Bristol Buckingham	Specification cancelled

E.9/44	Flying wing jet bomber/airliner	Armstrong Whitworth A.W.52

E.10/44	OR.182	Experimental Nene-powered jet fighter - Jet Spiteful	see N.5/45

N.11/44	OR.174	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

12/44	Medium range civil transport aircraft	Handley Page Hermes II

F.13/44	OR.194	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, Hawker P.1027/P.1030

S.14/44	OR.89	Naval land-based ASR	Supermarine Seagull ASR-1

N.15/44	OR.189	Naval carrier-version of Mosquito	de Havilland Sea Mosquito TR.33

16/44	Stop-gap airliner version of Lancaster	Avro Lancastrian C.Mk 1

17/44	Medium-short haul passenger aircraft - stop-gap airliner version of Wellington	Vickers Wellington Transport Aircraft

18/44	Brabazon Committee Type Va	Civil feederliner	Miles Marathon

19/44	Civil transport version of the Avro York C1	Avro York

20/44	Jet civil transport (de Havilland DH.106)	Not issued

O.21/44	Twin-Merlin engined Fairey Spearfish	Specification cancelled

22/44	Transport aircraft - mixed passenger, freight/passenger or all-freight high-payload/short-distance - see also G.9/45	Bristol Wayfarer/Freighter

E.1/45	OR.195	Experimental aircraft for research into proposed tailless configuration of early DH.106 Comet airliner design	de Havilland DH.108

A.2/45	OR.176	Army Air Observation Post (AOP) - replacement for Taylorcraft Auster AOPs	Auster A.2/45, Heston A.2/45

B.3/45	OR.199	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

B.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

A.4/45	OR.164	Army three-seat light communications aircraft - Leonides-powered Pioneer II later accepted 1950	Scottish Aviation Pioneer I

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

T.7/45	OR.159	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

TX.8/45	OR.180	Tandem-seat training glider for Air Training Corps	Slingsby T.24 Falcon 4

C.9/45	OR.192	Military transport aircraft capable of carrying a 3 ton load into jungle areas - see also 22/44	Bristol Wayfarer/Freighter

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.12/45	OR.213	Long-range carrier-based fighter - Wyvern with Python turboprop engine - see also F.13/44 & N.11/44	Westland Wyvern S.4

C.13/45	High speed military transport aircraft	Airspeed Ayrshire

C.15/45	Long range transport aircraft	Handley Page H.P.72

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

E.20/45	OR.221	Experimental helicopter - see also E.34/46	Bristol Type 171

N.21/45	OR.226	Naval carrier-borne two-seat night fighter	de Havilland Sea Hornet NF.21

Q.1/46	OR.225	Naval target tug	de Havilland Mosquito TT.39, Miles Monitor, Short Sturgeon TT.1,

2/46	Brabazon Committee Type I	Long range transatlantic airliner - Brabazon II (Coupled Proteus) order	Bristol Brabazon II

C.3/46	Medium-range tactical transport	General Aircraft Ltd. 65 Universal Freighter

N.3/46	Naval helicopter	Cierva Air Horse

E.4/46	Experimental gyrodyne	Fairey Gyrodyne

R.5/46	OR.200	Four engine long-range Maritime patrol bomber - Liberator GR replacement	Avro Shackleton

N.7/46	OR.218	Naval carrier-borne interceptor/fighter bomber	Hawker Sea Hawk

C.9/46	All-round air transport - military version of Viking	Vickers Valetta C.Mk.1

N.11/46	Two-seat trainer version of Sea Fury	Hawker Sea Fury T.20

B.14/46	OR.239	Four engine jet medium bomber - later used as insurance against delay of aircraft submitted to B.35/46	Short Sperrin

C.16/46	Brabazon Committee Type IIB	Short-medium range turboprop airliner carrying 24-30 passengers	Armstrong Whitworth A.W.55 Apollo, Handley Page H.P.76, Handley Page H.P.77, Handley Page H.P.78, Vickers Viscount

E.19/46	Experimental helicopter for crop spraying	Cierva Air Horse

22/46	Brabazon Committee Type IV	Jet-propelled trans-atlantic mail plane/jet airliner - MoS order for two Comet prototype/production aircraft	de Havilland Comet

26/46	Brabazon Committee Type II	Short-range feederliner - Dragon Rapide replacement	de Havilland Dove

E.27/46	OR.241	Experimental aircraft for investigation into delta wing characteristics at transonic speeds	Boulton Paul P.111

X.30/46	Assault glider	Shorts S.48 / S.A.9

PR.31/46	OR.223	Photo Reconnaissance version of B.3/45	English Electric Canberra PR3

E.34/46	OR.242	Experimental helicopter - see also E.20/45	Bristol Sycamore

B.35/46	OR.229	Four engine swept-wing jet medium 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, de Havilland DH.111, Handley Page Victor, Short PD.1; Designs also submitted by Vickers & English Electric

E.38/46	OR.243	Experimental aircraft for investigation into the controllability and stability of swept wings at low speeds.	Hawker P.1052

N.40/46	OR.246	Naval carrier-borne jet fighter - see also F.4/48	de Havilland DH.110

E.41/46	Experimental swept-wing version of Attacker - evolved into Swift	Supermarine 510, Supermarine Swift

R.42/46	Marine Reconnaissance Landplane (Avro Shackleton MR.III replacement) - cancelled	Avro Shackleton MR.IV

F.43/46	OR.228	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	OR.227	Two-seat twin-engined night/all weather fighter	see F.24/48 & F.4/48

T.1/47	OR.238	Two-seat trainer version of Meteor – written around Gloster's civil Meteor demonstrator G-AKPK	Gloster Meteor T.7

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

F.3/47	Fighter – Vampire with wing strengthened for carriage of underwing stores	de Havilland Vampire F.Mk.3

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

A.6/47	Two-seat Army Helicopter	Bristol Type 171

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	OR.254	Naval carrier-borne jet fighter/research aircraft	Supermarine Type 508, Supermarine Type 529

E.10/47	OR.252	Experimental research jet	Fairey Delta 1

T.14/47	OR.159	Two-seat advanced trainer using Merlin 35 – replacement for T.7/45 (q.v.)	Avro Athena T.2, Boulton Paul Balliol T.2

E.1/48	Small Jet Propelled Helicopter (not-built)	Isacco Helicogyre No. 5

R.2/48	OR.231	Reconnaissance flying boat, updated and renumbered as R.112D in 1950s but cancelled. Expected order for PD.2 suspended	Blackburn B-78, Saunders-Roe P.104/Saunders-Roe P.162, developed Short Shetland Short PD.2, Supermarine 524

F.3/48	OR.228	Written for P.1067, replaced F.43/46	Hawker P.1067 (Hawker Hunter), Bristol Type 177

F.4/48	OR.227	Two-seat twin-engined night/all weather fighter - replacement for Vampire NFs	de Havilland DH.110, Gloster Javelin

5/48	Long Range Empire Aircraft (cancelled)	Avro 709, Blackburn B-73, Fairey FC.4

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.7/48	Experimental unmanned target aircraft powered by turbojet engine - Queen Martinet replacement	Government Aircraft Factory Jindivik

T.8/48	OR.260	ab initio trainer - Tiger Moth replacement - written for Chipmunk T.10 production order	de Havilland Chipmunk T.10

B.9/48	OR.231	Four engine jet medium bomber - less advanced stop-gap for B.35/46 designs - written around Valiant	Vickers Valiant

10/48	Twin-engine crop sprayer (cancelled)	Cierva W.11T

11/48	Production of Avro Tudor IVB civil aircraft (cancelled)

T.12/48	Trainer - two-seat Wyvern conversion trainer	Westland Wyvern T.3

T.13/48	OR.249	Trainer - multi-engine - replacement for Wellington T.Mk 10	Vickers Varsity T.Mk 1

S.14/48	NAR.21, OR.264	Naval version of the Sikorsky S-51	Westland Dragonfly

E.15/48	no OR	Experimental one-third scale low-speed research version of Avro's B.35/46 design	Avro 707

T.16/48	OR.257	Trainer - Prentice replacement	Avro 714, Handley Page H.P.R.2, Percival Provost, Boulton Paul P.115, Boulton Paul P.116

T.17/48	OR.260	Primary Elementary Trainer	Fairey Primer

B.22/48	OR.302	Pathfinder version of Canberra	English Electric Canberra B.5

F.24/48	OR.265	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

T.1/49	OR.269	Navigation / AI trainer	Vickers Type 743 Valetta T.3

T.2/49	OR.244	Dual-control training version of Canberra	English Electric Canberra T.4

T.3/49	Flying classroom	Avro Anson - cancelled

E.4/49	Experimental aircraft for B.9/48	Vickers Type 663 Tay Viscount

F.5/49	Long range fighter for RAF

M.6/49	OR.275 / NRA/9	Light carrier-borne ASW - written around Short Sturgeon variant - spec derived from GR.17/45	Short S.B.3

7/49	not issued

N.8/49	NRA/18	Naval strike aircraft	de Havilland DH.109 cancelled

A.9/49	OR.274	Army / RAF evacuation helicopter	Bristol Sycamore HC.10 & Bristol Sycamore HC.11 prototypes

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

E.11/49	Experimental - flying shell of B.35/46	cancelled

12/49P	Proposed production of B.5/47 by English Electric	cancelled

A.13/49	OR.281	Army helicopter	Saunders-Roe Skeeter

N.14/49	NA/A.14	Naval carrier-borne all-weather strike fighter - see also N.40/46 & F.4/48	de Havilland Sea Vixen

F.15/49	OR.277	Jet fighter - interim Vampire replacement	de Havilland Venom

E.16/49	OR.282	Swept-wing Mach 2 research aircraft	Armstrong-Whitworth AW.58

T.17/49	NR/A20 & OR.283	Crew trainer for Royal Navy / FAA	Percival Sea Prince T.1

C.18/49	NR/A15 & OR.283	Communication aircraft	Percival Sea Prince C.1

19/49P	Transport - Hastings C.2 order	Handley Page Hastings C.2

A.20/49	OR.270	Air Observation Post Aircraft	Auster AOP.9, Percival O.68 and Percival P.69 tendered

A.20/49 Issue 2	Production Auster AOP.9	Auster AOP.9

21/49	Medium range passenger transport	Vickers VC.2 Type 630 Viscount

U.22/49	high speed pilotless target aircraft and launching ramp	GAF Jindivik II - cancelled

F.23/49	OR.268	Supersonic jet fighter/interceptor	English Electric P.1 & English Electric P.1A

F.23/49 Issue 2	OR.268 Issue 1	Three prototype supersonic jet fighter/interceptor aircraft	English Electric P.1B Lightning

F.23/49 Issue 3	OR.268 Issue 4	Three prototype supersonic jet fighter/interceptor aircraft	English Electric P.1B Lightning

F.23/49 Issue 4	OR.268 Issue 6	20 pre-production supersonic jet fighter/interceptor aircraft	English Electric P.1B Lightning

F.23/49 Issue 5	outline Specification for proposed German version	English Electric P.1B Lightning

23/49P	OR.268 Issue 6	Fifty production supersonic jet fighter/interceptor aircraft	English Electric Lightning F.1 & English Electric Lightning F.1A

23/49P.2	OR.268 Issue 6	Forty two production supersonic jet fighter/interceptor aircraft	English Electric Lightning F.2

23/49P.3	Forty seven production supersonic jet fighter/interceptor aircraft + 3 prototypes converted from a pre-prod a/c and two F.2s	English Electric Lightning F.3

H.24/49	Air ambulance helicopter (cancelled)	Fairey FB-1 Gyrodyne

U.25/49	Small low speed pilotless target aircraft and launching pad (cancelled replaced by U.120D)

26/49	Replacement for the de Havilland Rapide (cancelled)	Blackburn B-84, Folland Fo 134

E.27/49	[Configuration Research for F.23/49 (Cancelled and replaced with ER.100)	Short SB.5

F.28/49	Development of E.38/46 (P.1052) for Australian government.	Hawker P.1052

Sentence(s)

Avro began work on the Specification 29/43 of the Lancaster IV.

final_sentence: Avro began work on the Specification 29/43 of the Lancaster IV.