the ight envelope — looking at basic
functionality of the vehicle itself and the
structural integrity. We ew utter testing,
explored high-speed Mach e ects, high
Angle-of-Attack, weapons separation
including ejecting missiles from the bays
into the air ow.’
Speaking of some of the high Alpha test
work, Metz says: ‘It started in the simulator
to uncover problems here and there and
tweak the ight control computers. Then
we’d take it to ight test. Today, if a pilot
gets up there and does something funny,
they just have to centre the controls and
wait — the Raptor can recover itself.
A lot of the Raptor’s manoeuvrability
is achieved with the thrust vectoring,especially the pitch control. It uses the
control surfaces in an unconventional
way to obtain unusual responses. For
example the horizontal tails are individual
units and they can work symmetrically
or asymmetrically. So, I spent most of my
time on the handling side of things, but
also some of the initial avionics testing on
aircraft 4004 and 4005.’
This testing wasn’t entirely trouble free.
Weight reduction e orts on 4001/4002
had resulted in these two aircraft falling
below the required structural strength for
some of the more demanding envelope
expansion work. This was subsequently
delayed until the arrival of 4003, an
instrumented structural test aircraft,Above: Raptor
01 was retired
in 2000 and
moved to Wright
Patterson
for live re
testing. It is
now a GF-22A
and located at
Hill AFB, Utah,
where it is
used for battle
damage repair
training.
Left: Lt Col David
‘Doc’ Nelson
ew as part of
the Combined
Test Team
during the EMD
phase.(^24) RAPTOR
16-27 Metz First Flight C.indd 24 28/09/2017 14:53