The USAF ordered studies to look at
both air-to-air and air-to-ground roles
for the ATF, to assess if a single platform
could effectively fill both requirements. In
November 1981, the Pentagon authorised
the go-ahead for the development of a new
fighter, without any funds actually being
in place. The initiative drew a staggering
variety of design solutions from industry,
which eventually boiled down to the Air
Force finding a sweet spot in terms of size,
speed and manoeuvrability. What’s more,
the USAF started to focus on the air-to-
air mission in light of behind-the-scenes
developments with the F-15E Strike Eagle
and the F-117A Nighthawk.
By late 1982, the ATF had become a real
programme with significant funding as the
USAF set its priority on the air superiority
mission and directly replacing the F-15. A
final Request For Proposals (RFP) was issued
in 1983 and the USAF went into a Concept
Demonstration Investigation (CDI) phase
to help weed out the riskier offerings and
help downselect for a fly-off competition.
Concept definition studies were embarked
upon by Boeing, General Dynamics,
Grumman, Lockheed, McDonnell Douglas,
Northrop, and Rockwell. Interestingly, the
secrecy of the F-117 programme (which first
flew in 1981) was such that the ATF teams
were unaware of emerging technologies
that would help enable them to meet ATF
needs and combine stealth with high speed
and manoeuvrability. However, it appears
that during 1983 some of that relevant
information began to filter down from the
USAF to the ATF teams.
Following a period of evaluation, the
Lockheed YF-22 and Northrop YF-23 were
declared the winners on October 31, 1986,
and the companies were told to prepare
prototypes for a demonstration and
validation (DEM/VAL) phase. In parallel,
both Pratt & Whitney and General Electric
were contracted to develop and build new
engines; the YF119 and YF120 respectively.
Lockheed’s Code One Magazine reports:
‘A few months before the proposals for the
DEM/VAL phase of the programme were
to be submitted, the Air Force amended its
proposal request. The change significantly
increased the importance of stealth in
the design. Lockheed, with a stealthy
configuration derived from the F-117, made
no modifications to its design as a result
of the new requirements. Boeing made
some slight modifications to the design of
their inlet to address the increased stealth
requirements. The company was, however,
satisfied that its twin-tail design would meet
the stealth requirements.Left top to
bottom: A general
arrangement
drawing of an
early Lockheed
ATF design.
Lockheed had
completed the
first studies
by the early
1970s for a
‘superstealth’ air-
to-ground attack
platform for the
US Navy.
Lockheed’s
proposal
configuration,
called 090P, had a
wide strake that
ran in a straight
line from the
wing leading
edge outboard of
the inlets to the
point of the nose.
This Lockheed
diagram nicely
illustrates the
design evolution
of the F-22.
The Skunk Works
took the lead for
final assembly
of both YF-
prototypes.EARLY ATF DESIGNS
(^08) RAPTOR
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