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"In 1982, the Japanese government announced that they were seeking
a new warplane to succeed the Mitsubishi F-1 fighter support
aircraft. This led to a project known as the Next Fighter Support
Aircraft, or FS-X. The Japanese government contacted several
foreign aircraft manufacturers to see if existing types could meet
the FS-X requirement. At the same time, the indigenous Japanese
aircraft industry was approached to see if it were practical for
them to come up with a solution. Very rapidly, the contenders
narrowed down to the F-16 Fighting Falcon, the F/A-18 Hornet, the
Panavia Tornado IDS, and a possible indigenous aircraft. An
important requirement was the use of a Japanese-built datalink
system and the ability to carry the ASM-1 antiship missile.
The formal requirement was issued on November 22, 1985. The
aircraft was to have the ability to carry up to four antiship
missiles. In addition, the aircraft had to be able to carry 2-4
short-range AAMs and 2-4 medium- range AAMs, although not
necessarily at the same time as the antiship missiles were being
carried. An important requirement was a minimum combat radius of
450 nautical miles.
After looking over the responses, the Japanese Defense Agency
concluded that no existing aircraft was able to meet these
requirements. Only an indigenously-developed aircraft would do. The
three foreign contenders complained bitterly about being ruled out
in favor of an as-yet-nonexistent paper design. In addition, US and
European governments became involved because of the large trade
inbalances that existed between Japan and the economies of the USA
and Europe, and they pressured the Japanese government for a
reconsideration. As a result of the controversy, in April of 1986
the Japanese Defense Agency reissued its request, and all three
foreign contenders issued revised proposals.
The question now came down to whether a co-development of an
existing foreign aircraft would be selected, or if an entirely
indigenous aircraft would have to be developed from scratch. The
choice of an entirely new indigenous design would of course have
pleased the Japanese aviation industry, but the cost would have
been quite high and the project might be subject to lengthy delays
due to the need to start from scratch. If a foreign design were
selected instead, a considerable Japanese contribution to the
project would be required. The Tornado development was eliminated
at an early stage because of vague and unspecified concerns about a
co-development project with European aircraft industries being
somehow incompatible with Japanese security concerns. The revised
F/A-18 was dropped soon thereafter because of its high cost. On
September 11, 1987, it was announced that the choice had narrowed
down to an indigenous aircraft, or a development of the F-15 or
F-16.
On October 21, 1987, the Japanese government announced that it had
ruled out the solely indigenous option, and that it had selected a
development of the F-16C/D as the choice for the FS-X. The decision
was undoubtedly due to a lot of pressure from the US government.
The deal was also rather controversial in the USA at the time, with
critics charging that the US was giving away too much technology to
a competitor. Japanese Air Self Defense Force (JASDF) announced
plans to acquire as many as 130 FS-Xs to replace the Mitsubishi F-1
fighter bomber.
The prime contractor for the FS-X was Mitsubishi Heavy Industries,
in collaboration with General Dynamics (now Lockheed Martin). Fuji
Heavy Industries and Kawasaki Heavy Industries were important
subcontractors. It was agreed that 60 percent of the work would be
done in Japan, with the remaining 40 percent of the work being done
by American industries.
Mitsubshi was assigned the responsibility for the forward fuselage
and for all final assembly, with Kawasaki supplying the central
fuselage, the landing gear doors, and the engine access doors. Fuji
is responsible for the radome, the air intake, the starboard wing
(except for the leading edge flaps), wing root fairings, the
starboard wing flaperon, vertical tail surface and horizontal tail
surface. General Dynamics (later Lockheed Martin) was given the
port wing (with the exception of the flaperon), the starboard wing
leading edge flaps, and the rear fuselage. "
