North American B-25 Mitchell

History

Text about the development.

Versions.

North American B-25.

Of this, in fact pre production version just twenty-five examples were built, the first being delivered in February 1941.

These aircraft were armed with three .303 inch machine-guns, one in the nose, one through the floor and one pointing through the back plus one .50 machine-gun in the tail.

The first nine examples had a more or less straight wing, slightly pointing upwards. This configuration caused instability, so a new wing configuration in which the part of the wing pointing outwards from the engine was placed under an angle of zero degrees., the well known gull wing of the Mitchell . USAAC serials were 40-2165  till 40-2188

North American B-25A.

An improved version with armouring, an improved arrangement of machine-gun in the tail and furthermore self sealing fuel tanks in the wings Some forty examples of this version were built, USAAC serials  40-2189 till 40-2228.

North American B-25B.

The machine-gun in the tail was removed, the machine-gun arrangement on the back and belly position were replaced by a manned turret with two .50 inch machine-guns and a retractable, remote turret with also two .50 machine-guns,  in the lower position. 124 examples were built, with USAAC serial 40-2229 - 40-2348. The RAF received some of this series under the designation Mitchell Mk.I

Well known is the fact that the model B-25C and B-25D were virtually equal. The C was built in the North American-factory at Inglewood, the B-25D was built in the factory at Kansas City. The latter factory was set up by the US government in order to keep up the war production. Several production blocks which were distinguished by several modifications were built. In fact these types could be identified because of the slightly different wave between the Olive Drab and the Neutral Grey: Inglewood produced Mitchells had somewhat less proportional wave than the Kansas City produced examples

North American B-25C.

The first NEIAF order for 163 B-25Cs, designation NA-82 was signed September 24, 1940.
The B-25C resembled the earlier B-25B and differed in the R-2600-13 Double Cyclone engines with a Holley 1685HA carburettor, which replaced the Bendix Stromberg PD-13E-2 units. These were easier to maintain, but requested a careful de-icing. Further de-icing systems were added, a Stewart-Warner cockpit heating and the electrical system was now 24 Volt.

The armament was initially equal to the armament of the B-25B, to know one single 0.30-inch nose mounted machine gun two 0.50-inch machine guns in the dorsal turret and two 0.50-inch machine guns in a retractable ventral Bendix turret. Often this ventral turret was removed.
Another difference was the new type tail skid, this became a massive rubber skid used on all types to be produced. Also the single exhaust of each engine was shortened.

• From B-25C Fisc. Year no. 41-13176 the nose armament was enforced and became two .303 inch machine guns. A small transparent dorsal blister for the navigator was added from fisc. year no. 41-12817 Also the type of turret was changed in Bendix Amplidyne and an extra 304 US gallon external wing mounted fuel tanks could be used. (I have never seen photos of B-25s using these tanks.)
• B-25C-1 a wing mounted bomb rack was introduced also a torpedo could be used.
• B-25C-5 the 0.30-inch machine gun was replaced with a moveable 0.50-inch machine gun and a fixed 0.50-inch machine gun star board. Also the single exhaust was replaced with several shorter ones, just pointing out of the cowling.
• B-25C-10 mainly internal modifications.
• B-25C-15 Improved Clayton "S"-like flame damping exhaust for each cylinder was used. These exhausts were used on every succeeding B-25 model. Also an emergency system for the hydraulic landing gear was used.

North American B-25D.

The General Motors factory at Kansas City was leased by the North American Aviation in order to built the B-25 Mitchell. The Fisher Body Division of General Motors Corporation was the main contractor. The first order for the delivery of 1200 B-25Ds (NA-82) was signed June 28, 1941. North American/Inglewood produced the first parts for the first 100 B-25Ds.
The first B-25D's were delivered in February 1942. The B-25D was virtually identical to the B-25C and many modifications of the B-25D were parallel with the modifications of the B-25C.

• B-25D 41-29648 till 41-29797 two .303 inch machine guns were mounted, later replaced with two .50 machine guns.
• B-25D-10 mainly internal modifications were introduced.
• B-25D-15 Fisc year no. 41-30353 and on the improved Clayton "S"-like exhaust were introduced.
• B-25D-20 Fisc. Year no. 41-30533 modifications like clear vision wind screen; self sealing 230 gallon tank in bomb bay (every second aircraft); armour plating for the co pilot were added.
• B-25D-25, fisc. year no. 42-87138 and on a movable oxygen unit.
• B-25D-30 further “winterization” modifications and de-icing of the windscreen was added.
• The last version was B-25D-35.

North American B-25J

The B-25J (NA-108) was the last version to be produced. This model was built in the largest numbers. This model was produced in North American’s factory at Kansas City only. For a while both model B-25D and B-25J were built together. The first B-25J was delivered in December 1943; the last B-25D was delivered in March 1944. The medium bomber function of the B-25 returned with armament in the tail, turret, nose and blisters on both sides. Bomb racks and doors were electrically managed.
For the tailgunner heating was added. Three 1000 pound bombs could be carried and also two 1600-pound armour penetrating bombs could be carried. Also six 325 pound depth bombs could be carried under the wings.
The transparent nose section could be replaced with a solid nose with eight fixed 0.50-inch machine guns. Aircraft with this modification were designated B-25J-11, -17, -22, -27, -32, of -37, depending of the production block.

• B-25J-1 From fisc. year no. 43-4019 and on the provision for the 2000 pound bomb was deleted; these proofed to be in sufficient.
• B-25J-5 besides several internal modifications, de icing of the wind screen and gun-blast arrestors for the turret and blisters were added.
• B-25J-10 provision for wing mounted bomb racks were added; the electrical managed bomb racks and heating of the side armament was insufficient and removed.
• B-25J-15 Main modifications: Movable armament was equipped with new direction finders.
  The NEIAF Used B-25J-15s: N5-232 till N5-N5-241. N5-232 and N5-235 were handed over to the RAAF.
• B-25J-20 a second fixed 0.50-inch machine gun was installed in the nose. The moveable gun was relocated at a 4 inches higher position. The floor in the nose was armored. The canopy of the turret was strengthened and a hydraulic emergency brake was added.
  The NEIAF used B-25J-20s: N5-242 till N5-249.
• B-25J-25 Both pilot seats were armored; From fisc. year no 44-30111 armored deflector on the fuselage were used to prevent damage of the own plane by the gunner in the turrets.
  The NEIAF used B-25J-25s: N5-250 till N5-258 and N5-266.
• B-25J-30 the steel exhausts of cylinders 1, 7, and 9 were replaced with stainless steel examples. From fisc. year no 44-31311 an electrical bomb loading system was added. From fisc.year no. 44-31338 a provision for wing mounted rockets (T-64 rocket launchers for eight 5” HVAR (high-velocity aircraft rockets) was added. Later a provision to carry glide bombs was added.
  The NEIAF used B-25J-30s: N5-259 till N5-265.
• B-25J block 35 A provision for carrying mines was added. The transparent nose could be replaced with a solid nose with eight machine guns. The NEIAF modified several B-25J with this nose. These were designated as "B-25K".

1/72nd Scale

The Airfix, Matchbox and the old Frog/Novo-models are not recommended to built a good model of the Mitchell. To built a accurate 1/72nd scale model of the B-25C/D version, you can use the Italeri kits. Hasegawa released a very nice and accurate kit of the B-25J version in 2004.

C- and D-versions (Italeri kit):

In order to built an B-25C/D, based on the Italeri kit, of no 18 squadron NEI, the window just behind the canopy (part no 12) need to be reduced to half its size. The corners must be more rounded. Also this windows was somewhat bulgy (according to the photos of the real aircraft).

The windows, part 21, were, as far as i could see on photos, not present on the first C models. Also the oval windows (the parts just near part 12 in the frame of the kit) were present on the early C-versions.

The blister, part no 20, just aft the cockpit, was not present on the early C-models.

The most radical modification of the kit is that a small angle on top of the fuselage must be added. Remove a V shaped part from the fuselage. This must be about 2 mm at the end of the fuselage and zero millimetre near the ventral turret. Because of this modification you had to reshape the radome of the tail.

See the drawings.

Correction fuselage B-25C model Italeri

Later the aircraft had an extra fixed .50 inch machine gun added to the nose, so two fixed plus one movable machine gun were present. The kit has just on single machine gun, so check your scrap box or buy the guns in an accessory kit.

D-modified:

In the Pacific theatre more modifications were made and also been used by no 18 Squadron NEI. The B-25D-20 and later had additional gun packs added plus two machine guns pointing out of the windows just behind the wings. These windows are the same as used on the B-25J. Note that the location of these windows was identical!

Also these aircraft had an addition gun in the tail. A housing was added, note that this housing had a different shape than the housing of the B-25H and B-25J models, see the drawing added.
The Italeri PBJ-1D has a housing added with a tail gun, but this has a different shape and cannot be used for this version of the Mitchell.
What can be used from this kit are both gunpacks (parts 21 and 22). I think these packs might be some thicker. [By the way all parts for an ordinary B-25C are still with this kit]

Tail of a North American B-25D modified.

See this photo for a good impression of this blister. Note these blisters were slightly different from the blisters used on the first modified strafers!

J-version.

The J-version was usually fitted with two fixed machine guns plus one moveable machine gun in the nose. The kit has only one fixed gun available.

For all models you'll need to put an amount of extra weight in the front of the fuselage, to have model stand nice and easy on its landing gear.

• Airfix
  • Kit 04005: A B-25J with both transparent and solid nose. Fuselage is to narrow.
• ARK Models
  • Kit 72001: North American B25C Mitchell (ex FROG)
• Frog/Novo
  • Kit 159: A B-25C/D. An old model and hardly available. It was released with rather good decals for an aircraft of 320 (Dutch) squadron RAF.
• Hasegawa
  • 240E15 / 00839 / 00866 / 2400748: This is undoubtedly the best B-25J kit available at the moment. Parts for both a transparent and a strafer nose are included with the kit. Kit 2400748 contains decals for an aircraft of 320 squadron RAF
  • Kit 2402058: B25H Mitchell 'Nose Art'
  • Kit 240E17: B25H Mitchell
• Italeri
  • Kit 123: B-25B/C. The first released had a nose section in two parts with rather thick framing. In later releases of this kit the transparent nose section was one piece with a thinner framing. [also released by Bilek)
  • Kit 129: B-25H/J.
  • Kit 340043: N.A. 90 PBJ-1D (This is in fact the same as the B-25B/C kit, with some part added for a PBJ-version.)
• Matchbox
  • Kit 40411: A B-25G/H. The models of Matchbox are no longer available.
• Revell
  • Kit H2022: B-25B/C (Same as (first released) Italeri kit. No longer available.
  • Kit 04360: EB-25J; A release of the Hasegawa, with a lower price and decals for a Mitchells of 18 squadron NEI. Parts for a strafer version are added to the kit

Modelling add-on

• Aeroclub
  • Set P091: Hamilton Standard Hydro 12,6" (B25)
• Airwaves
  • Set C72157: Bombbay detailset B-25B-J
  • Set C72156: B25 Mitchell Cockpit Detail set (Airfix)
• Bilek
  • Set PB010: Detailset NA B25B/C Mitchell (Italeri/Bilek)
• CMK
  • Set A7142: B25J Mitchel Control surfaces t.b.v. Revell/Hasegawa
  • Set A7140: B25J Mitchell Exterior Detail set t.b.v. Revell/Hasegawa
  • Set A7141: B25J Mitchel Armament set (Revell/Hasegawa)
  • Set Q72063: NA B25 Mitchell wheels (Hasegawa)
• Eduard
  • Set E72-139: Bombbay detailleringsset B-25B-J
  • Set E72-166: Detailleringsset B25B/C
  • Set E72-140: Detailset B-25H/J
  • Set E72-423: Detailset B25J Mitchell Interior (Hasegawa)
  • Set E72-426: Detailset B25J Mitchell Interior (Hasegawa)
  • Set E72-425: Detailset B25J Mitchell Bomb bay (Hasegawa)
  • Set E72-424: Detailset B25J Mitchell exterior(Hasegawa)
  • Set SS327: North American B25J Mitchell Solid Nose - self adhesive (Revell/Hasegawa)
  • Set E73-327: Detailset B25J Mitchell solid nose interior self adhesive (Hobby Boss)
  • Set SS328: North American B25H Mitchell - self adhesive (Revell/Hasegawa)
  • Set E72-494: Detailset North American B25J Mitchell Solid Nose exterior (Hasegawa/Revell)
  • Set E72-447: Detailset B25H Mitchell exterior(Hasegawa)
  • Set E72-435: Detailset B25H Mitchell Bomb bay (Hasegawa)
  • Set E72-424: Detailset B25J Mitchell exterior(Hasegawa)
  • Set BIG7201: Detailset B25J Mitchell (Hasegawa)
  • Set BIG7255: Detailset B25J Mitchell Solid Nose (Hasegawa)
  • Set XS233: Express Mask B25J Mitchell (Hasegawa)
  • Set XS124: Express Mask B25C/D Mitchell (Italeri)
• Falcon Canopies
  • Set VAX46: USAF Part 4
• Neomega
  • Set M: Pratt & Whitney R2800 (F8F, F6F, P61, P47, B25)
  • Set M2: Pratt & Whitney R2600 (A20 B25, TBM/TBF)
• Obscureco Aircraft/span>
  • Set 72005: North American PBJ-1D/J Mitchell Conversion
• Part Etchings
  • Set S72-231: Detailset B25 Mitchell Bomb bay(Hasegawa)
  • Set S72-230: Detailset B25H Mitchell (Hasegawa)
  • Set S72-228: Detailset B25J Mitchell (Hasegawa
  • Set S72-227: Detailset B25 Mitchell Generic (Hasegawa)
• QuickBoost
  • Set QG72002: B25H/J Mitchell Corrected Cowlings (Revell/Hasegawa)
  • Set QG72030: B25 Mitchell Engines (Hasegawa)
  • Set QG72010: B25 Mitchell Props (Hasegawa)
  • Set Qg72055: B25B Mitchell Gun barrels (Hasegawa)
  • Set QG72025: B25B/C Mitchell Gun barrels
  • Set 72058: B25H Mitchell Gun barrels (Hasegawa)
• Scale Aircraft Conversions
  • Set 72010: NA B25 Mitchell Landing Gear (Hasegawa)
• Squadron/Signal
  • Set SQ9166: Canopies North American B25 Mitchell.
  • Set SQ9195: North American B25J Mitchell Canopy .
• Tasman
  • Set 232: B25B Mitchell Glass part set (Accurate Miniatures)
• True Detail
  • Set 72034: Wheels for B-25B – J.

Decals

• AviPrint:
  • Set 72005:: Decals for several NEIAF B-25Js e.g. N5-230 ML-KNIL
• DKdecals
  • Set 72007: B25 Mitchell in RAAF and NEIAF Service
• Dutch Decal
  • Set 72017: Decal for several aircraft such as B-25J M-451 (partly stripped of paiint).
  • Set 72033: Decals for several NEIAF Mitchells and some B-25s of 320 squadorn RAF. Note  N5-146 is a B-25C-15 with US-serial 42-32512. It was equipped with the later exhausts and two gunpacks with two .50 inch guns (see the photo on page 47 in Air Enthusiast nr 26); N5-126 should be N5-128, an B-25C with US-serial 41-12935.
  • Set 72079: Dutch Flags (B25 Mitchell, C54, Lockheed L12 (NEIAAF), B24 Liberator, Catalina, Do24 (MLD), Do24 (RAAF)
  • Set 72072: Dutchies in the RAF (Spitfire, Typhoon, Tempest, Mosquito, Halifax, Mitchell, Swordfish
• EagleCal
  • Set D7225: Decals for B-25C/D/J 320 squadron RAF.
• FlevoDecal
  • Set FD72-001: Royal Netherlands Navy part 1
  • Set FD72-003: Netherlands East Indies KNIL 1942-1947 part 1 (Hurricane, C47, C54, P40N, B25 Mitchell'
  • Set FD72-022: Royal Netherlands Historical Flight (B25, C45, S11, L21, Spitfire, T6 etc)

Scale 1/48

• Academy
  • Kit 12290: B25G Shark Mouth Mitchell
• Accurate
  • Kit 3432: North American B25G Mitchell
  • Kit 3431: North American B25C/D Mitchell
  • Kit 3430: North American B25B Mitchell
  • Kit 480030: North American B25C/D Mitchell 345 Bomb group "Air Apache"
• Italeri
  • Kit 342650: B25C/D Mitchell - !
• Monogram
  • Kit 15507: North American B25J Mitchell.
  • Kit 5512: North American B25J Mitchell (Glass Nose)
• Revell
  • Kit XX: Een B-25B/C.
  • Kit 0452: Een B-25J.
  • Kit 05725: B25J Mitchell "The Flying Bulls"
  • Kit 5528: B25J Mitchell Gun nose

Also in this scale several modifications need to be scratch build.

For an modelling article of a B-25 in scale 1/32 I refer to the article of Wim Nijenhuis in "Modelbouw in Plastic, number 3, 1978 (a release of IPMS Nederland).

Modelling add-on

• Aeromaster
  • Set D617: Conversion set for B-25H gunship
• Aires
  • Set 4097: B25B Mitchell Cockpit Detail set (Accurate Miniatures)
• Cutting Edge
  • Set BM48017: B25B thru J Mitchell Wheel Hub Masks
• True Detail
  • Set 48019: Wheelset
• Eduard
  • Set XF117: Express Mask B25 Mitchell (Revell/Monogram)
  • Set XF060: Express Mask B25B Mitchell (Accurate Miniatures)
  • Set FE327: Detailset B25G Mitchell (Accurate Miniatures)
  • Set FE322: Detailset B25B Mitchell (Accurate Miniatures)
  • Set E49-322: Detailset North American B25B Mitchell Interior (Accurate Miniatures/Italeri)
  • Set E48-524: Detailset B25G Mitchell Interior (Revell/Monogram, Accurate Miniatures)
  • Set big4862: Detailset B25G Mitchell (Accurate Miniatures)
  • Set big4861: Detailset B25B Mitchell (Accurate Miniatures/ Italeri)
  • Set E48-525: Detailset B25B Mitchell exterior (Accurate miniatures)
  • Set E48-261: Detailset North American B25J Mitchell (Monogram)
  • Set E48-260: Detailset North American B25G/H Mitchell (Monogram)
• Landing Zone
  • Set X: Corrected Cowls for B25C/D/G/J Mitchell
• Neomega
  • Set M2/48: Pratt & Whitney R2600 (A20 B25, TBM/TBF)
• Obscureco Aircraft
  • Set 48012: North American PBJ-1D/J Mitchell Conversion
• OK Resin
  • Set 48101: B25G Gunship (Accurate Miniatures)
  • Set 48102: B25H Gun nose Mitchell (Monogram)
  • Set 48103: B25 Mitchell Cowlings (late)
• Pavla
  • Set U48015: B25B Mitchel Nose interior (Accurate Miniatures/Italeri)
  • Set S48023: B25 Mitchell Seats (2x)
• Quickboost
  • Set 48038: B25G-H-J Cowlings
  • Set 48029: B25C-D Mitchell Gun barrels
  • Set 48022: North American B25B Mitchell Gun Barrels (Accurate)
• Scale Aircraft Conversions
  • Set 48055: North American B25J Mitchell Landing Gear (Monogram-Revell)
  • Set 48007: North American B25 Mitchell Landing Gear (Accurate Miniatures)
• Squadron
  • Set SQ09646: North American B25C/D Mitchell
  • Set SQ09645: North American B25B Mitchell
• Vector resin
  • Set 48010: Wright R2600
• Verlinden
  • Set 00001574: B25 Detail set (Accurate Miniatures)
  • Set 00001580: B25 Moving Surfaces (Accurate Miniatures)

Decals

• DKdecals
  • Set 48002: B25 Mitchell in RAAF and NEIAF Service
• Dutch Decal
  • Set 48017: Decals for several B-25 Mithcels of NEIAF and 320 squadron RAF.
  • Set 48018: Decals for several B-25 Mithcels of NEIAF and 320 squadron RAF.
  • Set 48056: B25B/D/J Mitchell ML-KNIL, NEIAAF part 1 1942-1945
  • Set 48047: Dutchies in the RAF: Mitchell MKII/III 320sq, RAF, Typhoon, Tempest, Mosquito, Spitfire
• EagleCal
  • Set D4825 : Decals voor B-25C/D/J van 320 squadron RAF.
• FlevoDecal
  • Set FD48-001: Royal Netherlands Navy part 1
  • Set FD48-003: Netherlands East Indies KNIL 1942-1947 part 1 (Hurricane, C47, C54, P40N, B25 Mitchell'
  • Set FD48-004: ML-KNIL Propaganda Mitchells
  • Set FD48-011: Historical Military Aviation in the Netherlands for aircraft such as B25

Literature.

Websites.

• NA B-25C USAF Museum
• NA B-25D USAF Museum
• NA B-25J USAF Museum
• Joe Baugher's Encyclopedie; NA B-25 Mitchell
• NA B-25C 41-12442
• Article written by Gerben Tornij
• F. Bonne: B25 Mitchell
• Strijdbewijs.nl: B-25
• Go2War2.nl: North American B-25
• Wikipedia UK: B-25 Mitchell
• www.B25.net
• B-25 Sarinah
• B-25 at MarsEtHitoria
• Article P. Boer at CortsStichtingen.nl
• B-25: ADF serials
• No 18 squadron NEI: at www.indie-1945-1950.nl>
• www.ozatwar.com/raaf
• www.ozatwar.com/ozcrashes
• Blister of a B-25D with twooe .50 machine guns
• Information about the PVA at www.hetdepot.com
• Information about the B25 at b-25factorytimes.nl