UNIT	COMMENT
B-29	Eight months before the attack on Pearl Harbor the USAAC issued a contract to purchase 250 Boeing B-29 bombers but it was only on June 5, 1944 (the day before D-Day) that B-29s flew on their first combat mission. Many of the innovations of the B-29 (pressurised cabins, remote controlled guns, radar controlled bombing) had appeared on other bomber prototypes but this aircraft was the first to bring them together in the one weapon. Beginning in March 1945 massed B-29s were used on low altitude incendiary raids over Japanese cities.
B-29A	Technically the only difference between the B-29 and the B-29A was the method of construction of the wing centre structure. However other changes were slipstreamed into the design during this production run including replacing the rear 20mm cannon with twin 0.50-inch machine guns.
B-29B	Lack of effective Japanese fighter opposition to the B-29 raids led the USAAC to remove most of the defensive armament from the B-29A to increase the bomb carrying capacity of the aircraft.  The sole remaining weapon was a twin 0.50-inch machine gun mount in the tail gunner position which was aimed and fired by an automatic radar fire control system. 
B-32	The Consolidated B-32 Dominator was ordered as an alternative in case the B-29 failed to perform to specification but delays in completion of its own test program gave the B-32 no chance to outshine its competitor. By the time the B-32 went into combat in the Philippines in May 1945 the writing was on the wall and the entire B-32 program was cancelled in September 1945. Only 118 units were built and at the end of the programme the aircraft were flown straight from the factory to the scrap yard. The planes specifications were similar to the B-29 with four 2,200 hp engines, ten 12.7mm machine guns and 9,000kg of bombs.
B-34	The Lockheed B-34 Ventura was a conversion from an existing Lockheed civilian aircraft which should have given Lockheed an excellent start in getting it into production. They proposed the idea to the British Air Ministry in September 1939 however it wasn’t until September 1941 that the RAF took delivery of its first Venturas. Four 7.9 mm and four 12.7mm machine guns plus a 1,500kg bomb gave the B-34 a good offensive punch in its role as a sea patrol and ASW aircraft but its high weight and poor survivability made it unpopular with aircrews. The Ventura served with the USAAC, USN, RAF, RAAF and the SAAF.
B-36	The prototype of the Consolidated Vultee B-36 Peacemaker first flew in 1946 with 383 units going into service between 1947 and 1959 as the stepping stone between the B-29 Superfortress and the B-52 Stratofortress. The use of pusher propellers on the six wing-mounted engines assisted flight characteristics but created icing problems at high altitudes. The 21 units of the B36-A production run of were used for crew conversion and later converted to RB-36E reconnaissance models which could reach 60,000 ft (18,000 m) with a 50 hour endurance.
B-36B	The B-36B was the first version of the Peacemaker to be deployed as a bomber. Its thirty tonne bomb load was eight times the capacity of the B-17 and with sixteen 20mm cannon in eight dual mounts the B36 was well able to defend itself. The anomaly of a piston-engine bomber being deployed as the mainstay bomber of the USAAF until the mid 1950's was explained because the gas-guzzling jet engines of alternative bomber designs could not provide the 13,000km range of the B-36.
B-50	The B-29D/B-50 was a standard B29A with engines upgraded from 2,200 hp to 3500 hp. It was renamed to B-50 because of the reluctance of Congress to sink money into anything perceived as WWII era technology. With a simple change of designation the USAAC could present the B-29D as a new design and obtain the funding. Although approval for the funding was achieved no B-50s were ever ever built.
B5N1	The Nakajima B5N1 Kate was the standard torpedo bomber for the IJN at the start of the WWII. It had entered service in 1938 and when teamed with the fearsome “Long Lance” torpedo it was quite capable of disposing of enemy shipping as shown at Pearl Harbor on December 7th 1941. It carried a torpedo or two 250kg bombs and its sole defensive armament was a single rear-mounted 7.7 machine gun.
B5N2	Combat losses in the China War at the hands of the Russian-built Polikarpov I-16 fighters serving with the Chinese air force forced the IJN to consider upgrades to the B5N1. Defensive features such as armor plate and self-sealing fuel tanks were dismissed in favour of upgrading the engine from 770hp to 1000 hp engine which boosted the top speed from 217 to 235 mph. The B5N2 first flew in December 1939. Total B5N production for all models was 1,149 aircraft.
B6N1	Although technically a new design, the Nakajima B6N Tenzan closely resembled the B5N Kate which it was designed to replace. Known to the Allies as “Jill” this aircraft carried a 1870hp engine and an additional rear-firing machine gun in a ventral tunnel. Only 133 B6N1’s were built before the introduction of the B6N2.
B6N2	Rationalisation of Japan’s engineering efforts forced Nakajima to use a less powerful 1850 hp engine for the 1,133 units of the B6N2 which were produced. Refined streamlining and other minor modifications limited the adverse effects of this engine downgrade. 
B7A2	The payload of the Aichi B7A Ryusei (allied codename of “Grace”) was similar to that of the B6N “Jill” torpedo plane and the D4Y “Judy” dive bomber which it was designed to replace, however the manoeuvrability of this new aircraft was more like that of a Zero. Its maximum speed of 566km/h and ceiling of 8950m made it a powerful air weapon but the destruction of the Aichi factory in Furutaka by an earthquake in May 1945 limited production to 117 units and the lack of carriers forced the IJN to operate these aircraft from land bases. 
BA 65	The Ba-65 was a failed attempt to produce an all-purpose fighter, recon and bomber. Although these aircraft achieved limited success against Russian aircraft during the Spanish Civil War they were unable to compete with Allied fighters during WWII and were rapidly withdrawn from service.
Ba-349	More of a manned missile than an aircraft, the Bachem BA-349 Natter was designed as a point defence weapon which would be positioned at expected enemy targets. It would launch vertically then boost for six minutes to reach its maximum altitude of 14,000m from where it would descend on the allied bomber formations to fire its single salvo of twentyfour 73mm rockets at a selected target. After the attack the Natter would self destruct with the pilot and recyclable engine descending by separate parachutes. The only test flight of the Natter in March 1945 resulted in the death of the pilot.
Baffin	Powering a two seater torpedo bomber with a 545hp engine may have seemed a good idea in 1932 but by the start of WWII the Blackburn B-5 Baffin was clearly outclassed. Some units served with the RNZAF.
Barracuda	
Barracuda Mk.I	It took until January 1943 for the Fleet Air Arm to introduce their first monoplane torpedo bomber to replace the existing biplane Swordfish and Albacore bombers. The 1,260hp engine of the Mark I version was underpowered and the Mark II was rapidly introduced with a 1,640hp engine. In April 1944 Fairey Barracudas flying from HMS Victorious executed Operation ‘Tungsten’ by attacking the German battleship Tirpitz while it was sheltering in a Norwegian fjord.
Barracuda Mk.V	The last production model of the Barracuda was the Mark V of which 30 units were produced before production ceased at the end of the war in 1945. Fairy Barracudas serving with the British Pacific Fleet took part in raids against the Japanese home islands in 1944 and 1945.
Battle	The Fairey Battle first flew in March 1936 and had many of the features required by modern tactical bombers serving in WWII including retractable undercarriage, variable-pitch propellers, cockpit canopies and an all-metal construction. Unfortunately its 1,030hp engine and the armament of two 7.7mm machine guns (one firing forward and one firing to the rear) was insufficient to keep its 3 man crew out of danger. Fairey Battles suffered badly against the Luftwaffe in the Battle for France in 1940.
Beaufighter Mk.21	The Australian made Mk.21 version of the Beaufighter replaced the torpedo armament of the Mk.X with two 250lb bombs and eight rockets. They first flew in May 1944 and were equipped with a Sperry autopilot.
Beaufighter Mk.I	The Bristol Beaufighter was a company funded variant of the existing Bristol Beaufort Torpedo Bomber. This initial investment paid off handsomely for the company when the British Air Ministry ordered 300 units ‘off the drawing board’ in July 1939. The Beaufighter Mark I was powered by two 1,400hp engines but could could only reach 497kph which meant that it was measurably slower than the RAF's 523kph Hawker Hurricane. The decision was made to equip the Beaufighter as a nightfighter where its long airborne endurance would allow it to fly standing patrols against German raiders.
Beaufighter Mk.IF	The Beaufighters Mk.IF (the 'F' indicating 'Fighter Command') first became operational in October 1940 with their deployment as nightfighters equipping No 29 squadron of the RAF. The combination of four belly-mounted 20mm cannon with six 7.9mm machine-guns in the wings allowed prompt dispatch of any German aircraft caught in the scope of Beaufighter’s airborne AI Mk IV radar. 
Beaufighter Mk.VIC	The Beaufighters Mk.VIC (the 'C' indicating 'Coastal Command') arrived in early 1942 powered by upgraded 1,650 hp Hercules engines and provision for carrying torpedos. 
Beaufighter Mk.VIF	The Beaufighter Mk.VIF equipped night fighter units beginning in March 1942 and saw service in Europe and North Africa. In a rare occurence of reverse Lend-Lease four US units in the Mediterranean operated Mk.VIF's until the arrival of the P-61 night-fighter. Mk.VIF's arrived in the Far East in 1942 and the aircraft's effectiveness caused the Japanese to name them 'Whispering Death'.
Beaufighter Mk.X	The last and most numerous version of the Beaufighter was the Mk X powered by two 1,735 hp engines which could carry a large torpedo or bombs and rocket projectiles and was quite effective in ASW warfare against German submarines. A rear-firing 7.9mm machine gun was added to the observers position.
Beaufort Mk.I	The first Bristol Beaufort Mk.1 torpedo bomber with 1,035hp engines was delivered to the RAF in November 1939. One unit was shipped to Australia as a pattern for antipodean production of the Bristol Beaufort Mk.VIII. 
Beaufort Mk.II	The Bristol Beaufort Mk.II was equipped with two 1,200hp engines.
Beaufort Mk.VIII	The Australian built Bristol Beaufort Mk.VIII was equipped with two 1,200hp engines. The engine design was used to build the Boomerang fighter.
Bf-109B	The Bf-109 (also tagged as the Me-109) series of fighters was the most produced fighter aircraft of all time with over 33,000 units produced. The Bf-109A design with two 7.9mm machine guns was scrapped prior to production in favour of the Bf-109B which added a third machine gun firing through the propeller hub. The 'B' model entered service in February 1937 and saw combat during the Spanish Civil War.
Bf-109C	The Bf-109C increased the engine from 610hp to 700hp and changed the armament to four 7.9mm machine guns with two mounted above the engine and one in each wing.
Bf-109E1	The Bf-109E1 increased the engine to 1,015hp and some sub-variants replaced each of the wing mounted machine guns with a 20mm cannon. The E1 version included the first use of a Bf 109 as fighter-bomber.  
Bf-109E2	The Bf-109E2 description was never assigned to a production version of a Bf-109. 
Bf-109E3	The Bf-109E3 added armor protection for the pilot, increased the engine to 1,175hp and standardised the armament as two 7.9mm machine guns and two 20mm cannon.  Ten Bf-109E3 were modified into the Bf-109T-0 variant for deployment on the Kreigsmarine’s Graf Zeppelin. An E-3 was sent to where it influenced the design of the Kawasaki Ki-61 Hien known to the allies as the "Tony". 
Bf-109E4	The Bf-109E4 with additional armor was the standard production unit during the Battle of Britain in 1940. Some later E-4 models were fitted with a 1,175hp engine.
Bf-109E7	The addition of a belly-mounted drop tank increased the range of the Bf-109E7 by 50% over earlier versions.
Bf-109F1	The Bf-109F1 incorporated many structural changes, some of which prevented using wing-mounted guns. The armament was therefore reduced to two 7.9mm and one 20mm cannon all mounted on the engine. The success of the F-series design defined the aerodynamic specification for all future models of the Bf-109.
Bf-109F2	The Bf-109F2 was fitted with a 15mm engine-mounted cannon instead of the 20mm weapon used on earlier versions.
Bf-109F3	The Bf-109F3 was equipped with a 1.350hp engine.
Bf-109F4	The engine-mounted cannon reverted to the 20mm calibre.
Bf-109G1	The Bf-109G “Gustav” series was the most produced of all the Bf-109 variants. The G1 was equipped with a 1475hp engine
Bf-109G10	The Bf-109G10 designation covered a wide variety of production subtypes and field upgrades. Its distinguishing feature was a canopy bulge which gave the pilot a better field of vision.
Bf-109G2	The Bf-109G2 introduced twin underwing (rather than centreline) drop tanks. Locally built variants of the G2 with Rolls-Royce Merlin engines were produced in Spain until 1956 and flew in front-line service until 1964.
Bf-109G6	The G-6 model, the most produced Bf 109 version, had very heavy armament. The G-6/U4 variant with Rüstsatz R6 was armed with two 12.9mm (increased from the previous 7.9mm standard)  above the engine, a 30 mm MK 108 cannon shooting through the propeller axis and one 20 mm MG 151/20 in each wing
Bf-109K2	Armament was a 30 mm engine-mounted cannon and two 12.9 mm machine guns in the nose with an optional wing armament of additional cannons or R4M rockets. 
Bf-109K4	Addition of a pressurised cabin to the Bf-109K2 created the Bf109K4. The Me 109K-4 was the fastest 109 of WW2 with a top speed of 732 km/h. 
Bf-109K6	The K-6 was designed to carry one 30mm cannon in each wing with a third firing through its propeller hub plus two 12.9mm machine guns mounted above the engine. 
Bf-110C	The Bf-110C was the first production version of this long range fighter and it entered service in 1939 powered by two 1,100hp engines. It fared well during the initial months of the war when employed against Poland and France but was severely mauled by RAF Spitfires and Hurricanes when it was tasked to escort German bombers during the Battle of Britain in 1940.  The Bf-110C-4/B fighter-bomber variant carried two 250kg bombs.
Bf-110D	The Bf-110D was a Bf-110C with additional fuel tanks which would permit the Bf-110Ds of Luftflotte V stationed in Norway to escort bombers against Scotland and the north of England.  Unfortunately their first daylight foray across the North Sea on August 15th 1940 to attack airfields in the north of England lost eight of the 63 He 111 bombers and seven of the 21 Bf 110 escorts to the intercepting RAF fighters.
Bf-110E	A strengthenend airframe allowed up to 1200kg bombload.
Bf-110G	The failure of the Bf-210 replacement for the Bf-110 prompted the development of the Bf-110 G-series with two 1475 hp engines. This model was introduced in early 1943 and saw extensive service as a night fighter.
BF2C	Instantly recognisable by its distinctive fuselage-mounted retractable landing gear, the Curtiss-Wright BF2C-1 Goshawk fighter-bomber was plagued by a severe vibration problem which peaked at the aircraft’s cruising speed. Replacing the metal wings with wooden counterparts fixed the vibration but could hardly be considered an upgrade in technology. A squadron of these aircraft served aboard the USS Ranger (CV-4) from October 1936 to November 1937 until they were removed from service and replaced by their immediate predecessor in that role - the Boeing F4B-4. Henceforth Curtiss would concentrate their development efforts on land based fighters such as the P-36 and P-40.
Bl-210	Design flaws within the Me-210 Hornet prevented it from fulfilling its designated role as a replacement for the Bf-110. Some Luftwaffe units were equipped with this fighter starting in April 1942 but production was halted after only 90 units and the factories reverted to producing the supposedly obsolete Bf-110. The handling problems were eventually solved by lengthening the fuselage and upgrading the engines and production restart in mid 1943, but by then the Bf-210 had developed such a bad reputation that the aircraft had to be renamed as the Bf-410.
Blenheim Mk.I	When the Bristol Type 135 with two 840hp Mercury engines first flew in April 1935 its top speed of almost 500kph was faster than any RAF fighter then in service. A contract was placed by the Air Ministry and deliveries started in March 1937. By January 1940 26 squadrons of RAF Bomber Command were equipped with Blenheims but unfortunately the military version of the aircraft could only achieve 460kph which made it slower than Luftwaffe fighters.
Blenheim Mk.IV	The Blenheim Mark.IV (known as the Bolingbroke in Canada) featured upgraded 905hp engines and doubled the single 7.9 machine gun in the Mark.I's dorsal turret. The nose was lengthened to provide a position for a bombardier but this created visibility problems for the pilot during takeoff and landing so the characteristic asymmetrical nose with its lower port side was fitted to the production versions. The Blenheim Mark.IV could reach 475kph but it proved too fragile to survive on the battlefield as demonstrated by RAF 82 squadron which lost eleven out of twelve aircraft in a single raid in May 1940 over Namur and then suffered the same loss ratio a second time when attacking Aalborg airfield in Denmark in August 1940.
Bloch 175	The Bloch MB-174 entered service in March 1940 as a bomber/recon aircraft however the French Armee de l’Air soon realised that the 400kg bombload carried as eight individual 50kg bombs was inadequate. A rapid redesign modified the bomb-bay to accept 200kg bombs but only 25 of these MB-175 series were completed prior to the fall of France.
Boomerang	After the start of the Pacific War it took the Commonwealth Aircraft Corporation only four months of design and construction work to fly the prototype of the CA-12 Boomerang. The 1200 hp engines already being made under license in Australia for locally produced Bristol Beaufort bombers were mated with the frames of the existing CAC Wirraway trainer to create the first fighter to be designed and built in Australia.  Although maneauverable and well armored and with good firepower consisting of two 20 mm cannon and four .303 machine guns, the inadequate maximum speed of 490 km/h and poor high altitude performance meant that the Boomerang found its niche in ground support rather than dogfighting. 
BR 20	The FIAT BR.20 Cicogna (Stork) entered service in November 1936 and saw action with the Nationalist forces in the Spanish Civil War. It performed well in that arena but was severely outclassed when fighting the British in the Mediterranean and during the Battle of Britain. Eighty five of these aircraft were exported to Japan where they served in the China war as the Army type 1 Heavy Bomber model 100 known to the allies as “Ruth”.
BR 20bis	The FIAT BR.20.Bis had increased defensive firepower compared with the original BR.20 and could achieve a maximum speed of 460kph by upgrading the 1,030hp engines to 1,250hp and using an improved aerodynamic design. This version never reached production status owing to the Regia Aeronautica’s decision to standardise on the CANT Z.1018 bomber.
Breguet 693	Originally conceived as a three seat fighter, the Breguet 693 evolved into a two seat light bomber powered by two 700hp engines. It carried 400kg of bombs plus an unusual configuration of guns. The forward facing 20 mm Hispano-Suiza cannon and two 7.5 mm machine guns mounted in the nose could be depressed 15° for use in the ground-attack role and later production models included a rear firing 7.5 mm machine-gun installed in the tail of each engine nacelle. After the Fall of France in 1940 many surviving Breguet 693 were taken over by Italy and used in training and other rear-echelon roles.