The North American B-25 Mitchell was an American twin-engine, medium bomber manufactured by North American Aviation (NAA).
The design was named in honor of Major General William "Billy" Mitchell, a pioneer of U.S. military aviation. Used by many Allied air forces, the B-25 served in every theater of World War II and after the war ended many remained in service, operating across four decades. Produced in numerous variants, nearly 10,000 Mitchells rolled from NAA factories.
The
B-25C was the first version of the Mitchell to be mass-produced. Following the
completion of the initial B-25, B-25A, and B-25B contracts, a number of
contracts were awarded to North American for 1625 B-25Cs to be built at its
Inglewood factory. At the same time, an additional contract was issued for 2290
essentially identical B-25Ds, to be built at a new North American plant in
Kansas City, Kansas.
The
first B-25C contract was approved on September 24, 1940 for 863 aircraft under
the company designation NA-82. On June 24, 1941, the Netherlands government
ordered an additional 162 aircraft under the designation NA-90 which were later
built as the B-25C-5. Lend-Lease funds financed contracts signed on January 23,
1942 for 150 NA-94 (B-25C-10) for Britain and 150 NA-93 (B-25C-15) for China.
However, these allotments were not followed in the delivery of actual aircraft.
The
B-25C was outwardly almost identical to the B-25B. It introduced the R-2600-13
Double Cyclone engine with Holley 1685HA carburetors in place of the earlier
Bendix Stromberg PD-13E-2 units. The Bendix carburetors were favored because of
their easier maintenance, but they required more careful anti-icing procedures.
De-icer and anti-icing systems were added, and a Stewart-Warner cabin heater
was added in the left wing. A 24-volt electrical system was also added.
The
armament of the B-25C was the same as that of the B-25B, namely a single
0.30-inch machine gun in the nose, two 0.50-inch machine guns in the dorsal
turret, and two 0.50-inch machine guns in a retractable ventral turret. The
ventral turret was often removed in the field.
The
B-25C introduced a new type of tail skid underneath the extreme rear fuselage,
a solid unit which replaced the spring-loaded tail skid of earlier versions.
This type of tail skid was retained throughout the Mitchell production run.
On
the earlier B-25s, the exhaust pipe coming out of the back of the engines
extended all the way to a position underneath the forward leading edge of the
wing. On the B-25C, the exhaust pipes were considerably shortened, and
terminated immediately behind the engines.
The
fuel was carried in four tanks in the inner wing panels, with a total capacity
of 670 US gallons. In addition, a 515-gallon tank could be installed in the
bomb bay for ferrying purposes, bringing total fuel capacity to 1255 US
gallons.
Beginning
with B-25C serial number 41-12817, a small transparent scanning blister was installed
above the navigator's station. At this time, the turrets were changed to Bendix
Amplidyne type, and a carbureter air filter was added. Changes were made so
that an additional 304 US gallons of fuel could be carried in auxiliary cells
in the outer wing panels, for a total of 974 US gallons.
The
B-25C-1 production block introduced under-wing bomb racks which could
accommodate six to eight 100- to 325-pound bombs. In addition, provisions were
made for a rack underneath the fuselage capable of carrying a short 22.4-inch
torpedo weighing 2000 pounds. If the torpedo was carried, no bombs could be,
although a bomb bay fuel tank could be used. The Mitchell was employed only in
limited numbers as a torpedo plane against Japanese shipping. However, extensive
use was made of the external wing racks, which could carry six to eight bombs
of 100-325 pounds in weight.
Beginning
with the B-25C-5 production block, the 0.30-inch nose gun was removed and
replaced by a flexible 0.50-inch machine gun in the extreme nose and a fixed
0.50-inch machine mounted on the starboard side of the nose and firing through
a hole cut into the side of the Plexiglas glazing. At the same time, better
winterization provision were made.
The
B-25C-5 production block also introduced a new type of engine exhaust. The
B-25B and earlier C versions had a problem with bright spurts of flame being
emitted from the exhaust, a dead giveaway during night operations. This problem
was so bad that the Mitchell had to be restricted from night operations where
enemy aircraft could be expected. In these earlier versions, the exhaust from
each cylinder head was gathered by a collector ring, which directed the exhaust
to the outside via a single pipe on the side of the nacelle away from the
fuselage. Several different exhaust modifications were tried out in an attempt
to alleviate this problem. The most effective arrangement was found to be a the
replacement of the single exhaust pipe by a set of "finger"-type
flame dampening exhaust collectors which ported the exhaust through groups of
small rectangular outlets that stuck out underneath the trailing edge of the
cowl flaps. These "finger"-type flame dampeners were installed on the
production line beginning with the B-25C-5 production block. These were fairly
effective flame quenchers, but they suffered considerable cracking and few
B-25Cs reached combat zones without the replacement of these finger exhausts by
full collector rings or by the later Clayton S-shaped stacks that were
introduced on the -15 production block.
The
B-25C-10 production block introduced an AM remote reading compass, provisions
for additional cabin heating, and an improved scanning lens for the sig.
Beginning
with the B-25C-15 production block, the exhaust collector ring was replaced
with Clayton "S"-shaped flame dampening stacks attached to each
individual cylinder. Cutouts and fairings were added to the cowling panels
where each of the stacks protruded, creating a rather cluttered cowling shape.
These protrusions introduced a slight speed penalty, but this was considered an
acceptable tradeoff in view of the better flame dampening that was achieved.
This feature was provided on all subsequent Mitchells. However, the new exhaust
system was not all that popular with Mitchell crews, since it resulted in an
increase in cockpit noise as compared to the old arrangement in which collector
rings ported the exhaust to the outboard side of the nacelles.
At
the same time, emergency hydraulic landing gear lowering devices were provided.
Deliveries
on a new contract (NA-96) began in February 1943 with the similar B-25C-20.
Beginning
with production block B-25C-25, a "clear-vision" windshield was
installed. Provisions were made for the fitting of additional fuel tanks for
ferrying purposes. 125 gallons of fuel could be carried in side-mounted tanks
in the waist position. A 215-gallon self-sealing fuel tank could be installed
in the bomb bay, and provisions for a droppable 335-gallon metal bomb-bay fuel
tank were made on every second airplane.
B-25C
serial number 43-32732 was fitted with a special bomb bay rack to carry an
airborne flame thrower. The results of tests with this unusual feature are
unknown.
The
first B-25C was accepted in December of 1941, with the 1619th and last one
being delivered in May of 1943.
Serials of North American B-25C Mitchell
41-12434/13038 North American B-25C Mitchell
c/n 82-5069/82-5673
41-13039/13296 North American B-25C-1 Mitchell
c/n 82-5674/82-5931
42-32233/32382 North American B-25C-10 Mitchell
c/n 94-12641/94-12790
42-32383/32532 North American B-25C-15 Mitchell
c/n 93-12491/93-12640
42-53332/53493 North American B-25C-5 Mitchell
c/n 90-11819/90-11980
42-64502/64701 North American B-25C-20 Mitchell
c/n 96-16381/96-16580
42-64702/64801 North American B-25C-25 Mitchell
c/n 96-16581/96-16680
Specification of the North American B-25C Mitchell:
Engines:
Two Wright R-2600-13 Double Cyclone fourteen-cylinder air-cooled radials, each
rated at 1700 hp each for takeoff, 1500 hp at 2400 rpm. Equipped with Holley
1685HA carburetors. Performance: Maximum speed 284 mph at 15,000 feet. Cruising
speed 233 mph at 15,000 feet. Initial climb rate 1100 feet per minute. An
altitude of 15,000 feet could be reached in 16.5 minutes. Service ceiling 24,000
feet, Range 1500 miles with 3000 pounds of bombs. Weights: 20,300 pounds empty,
34,000 pounds maximum loaded. Dimensions: wingspan 67 feet 67.7 inches, length
53 feet 0 inches, height 15 feet 9 inches, wing area 610 square feet. Fuel: The
fuel capacity consisted of four tanks in the inner wing panels, with a total
capacity of 670 US gallons. In addition, a 515-gallon tank could be installed
in the bomb bay for ferrying purposes, bringing total fuel capacity to 1255 US
gallons. Later versions had additional auxiliary fuel tanks in the outer wing
panels. Later versions could also have 125-gallon tanks fitted in side waist
positions, a 215-gallon self-sealing fuel tank installed in the bomb bay, and
provisions could be made for a droppable 335-gallon metal bomb-bay fuel tank.
the waist position. Armament: Two 0.50-inch machine guns in dorsal turret. Two
0.50-inch machine guns in retractable ventral turret. One 0.30-inch machine gun
in flexible mount in the nose. Starting with B-25C-5 the 0.30-inch nose gun was
removed and replaced by a flexible 0.50-inch machine gun in the extreme nose
and a fixed 0.50-inch machine mounted on the starboard side of the nose and
firing through a hole cut into the side of the Plexiglas glazing. Normal bomb
load was 3000 pounds but could be increased on the B-25C-1-NA with external
underwing racks to a maximum of 5200 pounds.
Sources:
- B-25 Mitchell: The Magnificent Medium, N. L.
Avery, Phalanx, 1992.
- Medium with the Mostest--The B-25 Mitchell, Jerry
Scutts, Air International, Vol. 44, Nos 2 and 3, 1993.
- Boston, Mitchell, and Liberator in Australian
Service, Stewart Wilson, Aerospace Publications, 1992.
- Famous Bombers of the Second World War, William
Green, Doubleday, 1959.
- North American's Flying Gun--The Story of the
B-25 From Paper Airplane to Legendary Bomber, Jack Dean, Wings, Vol 23 No
4, 1993.
- United States Military Aircraft Since 1909,
Gordon Swanborough and Peter M. Bowers, Smithsonian, 1989.
- United States Navy Aircraft Since 1911, Gordon
Swanborough and Peter M. Bowers, Naval Institute Press, 1990.
- North American B-25A-G Mitchell, Aircraft in
Profile, Doubleday, 1966.
- Jane's American Fighting Aircraft of the 20th
Century, Michael J. H. Taylor.
B-25D through block 20 the series was near identical to the B-25C. The series designation differentiated that the B-25D was made in Kansas City, Kansas, whereas the B-25C was made in Inglewood, California. Later blocks with interim armament upgrades were the D2. First flew on 3 January 1942. (Number made: 2,290.)
The Kit
The box contains a very comprehensive instructions manual with two large (A2 format) sheets with colour painting guideline and stencils decals positioning.It also contains 5 grey sprues with parts and 2 clear sprues with clear parts totalling 168 parts (144 grey and 24 clear).
There are 2 decal options:
1- NA B-25D-15 Mitchell. 23 Anti-submarine Squadron 41-30409 "Lady Jane" (Tampa, FL July 1943)
2- NA B-25C Mitchell. 81 BS (medium) / 12 BG (medium) 41-12480 "Desert Warrior"
The parts are exceptional with crisp details e nice recessed panel lines
Steps
As usual, the construction begins by the cockpit which seems to be well detailed for the scale and considering it will be enclosed. There is a recommendation to add 25gr weight on the nose landing gear bay to prevent tail sitting ( I particularly don't think to be able to squeeze that much weight in that area, but we need to remember that the landing gear door is mostly closed when the aircraft is landed.
The bomb bay is very well detailed and you have the option to leave it open or closed.
The wings comes with a reinforcement which is nice to see in this small scale. it looks very well moulded and detailed.
The tail plane allows you to have the rudder in different positions.
The engine mounts and main landing gear are also well detailed. The landing gear needs to be fixed prior the engine boom and it will probably require extra care to not to be knocked off during building handling. I'll probably squeeze a few lead pellets in the back of the engine to prevent tail sitting since there is not much space on the nose and cockpit area. You have the option to make the aircraft in flight with all landing gear doors closed. Main wheel comes in two parts and looks all right.
You also have the option to have the flaps up or down.
Machine guns turrets are very well detailed. The underside turret can be built in two positions. Both sub-assemblies can be added after painting which is very good.
There are two types of windshield model you can choose depending on the model you are building. All clear parts looks very clear and free of distortion.
Conclusion
In box the kit looks exceptional and definitely is the best B-25C/D in the market. Airfix has raised the standard with this kit. I highly recommend it and I can't wait to start building it.
Model courtesy of my own pocket!
Cheers
