|
The B-25
medium bomber was one of America's most famous airplanes
of WW II. It was the type used by General Doolittle for
the
Tokyo Raid
on April 18, 1942. Subsequently, it saw duty in every
combat area being flown by the Dutch, British, Chinese,
Russians and Australians in addition to our own U.S.
forces. Although the airplane was originally intended
for level bombing from medium altitudes, it was used
extensively in the Pacific area for bombing Japanese
airfields from treetop level and for strafing and skip
bombing enemy shipping.
More than 9,800 B-25s
were built during WW II. The airplane on display was
rebuilt by North American to the configuration of the
B-25B used on the Tokyo Raid and was flown to the Air
Force Museum in April 1958.
The B-25 can trace its lineage back to the mid-1930s
development of the XB-21 (Model NA-39). Only one twin-engined
XB-21 was built, but North American used experience
gained for the company financed NA-40 project. This
aircraft was also a twin-engine design but had a
tricycle landing gear rather than the tail-dragger
configuration of the XB-21. Only one NA-40 was built and
it had several modifications done to test various
features including an engine change. The original Pratt
& Whitney R-1830 engines were replaced by Wright R-2600s
which would become standard on the B-25.
The NA-40B was initially submitted for evaluation as an
attack bomber for export use by Great Britain and France
which had an immediate need for aircraft in the early
stages of WWII. The aircraft lost to what would become
the Douglas A-20 "Havoc" but gained new life when it was
evaluated for use as a medium bomber even though the
aircraft was destroyed in a crash on 11 April 1939.
The redesigned NA-40B was designated NA-62 by North
American and along with the Martin B-26 was selected for
production in 1939. 184 aircraft were ordered and would
eventually be delivered as 24 B-25s, 40 B-25As and 120
B-25Bs. The B-25 was so desperately needed, no
experimental or service test (XB-25 or YB-25) aircraft
were built. Changes to the basic design were
incorporated into aircraft on the production line and
post-production or depot modification centers. One
significant change involved a design of the wing. The
first nine B-25s were built with constant dihedral
(angle) wings; however, stability problems forced a
change which kept the dihedral angle on the inboard wing
but nullified it on the outboard wing (0 angle). This
gave the B-25 its distinctive 'gull wing.' Another
change replaced smaller angled vertical stabilizers with
larger less angled ones.
Before production ended, about 10,000 B-25s were built
of all types which included a reconnaissance (F-10) and
Navy version (PBJ-1). The B-25 was also used by numerous
foreign countries including Great Britain which received
more than 900 aircraft by war's end.
|
