In the surreal world of amplified light, things aren’t as
they appear. That’s why a new simulator for fighter pilots
will ease the dangers of training with night-vision goggles.
Instructors said the simulator will enable them to teach pilots
on the ground, in an environment where violating safety procedures
doesn’t have such profound consequences.
“It’s totally a safety issue,” said Maj. Jonathan
Beasley, an instructor pilot with the 56th Training Squadron at
Luke Air Force Base, Ariz. “If you look at all the mishaps
we’ve had in fighters using goggles, almost all of them were
caused by reliance on some type of visual cue that you’re
not supposed to be relying on with night-vision devices.”
During the initial few rides, pilots often are uncomfortable and
disoriented, noted Maj. Jeff Johnson, an instructor pilot with the
310th Fighter Squadron. “It’s a different perception
that messes with their equilibrium.”
Currently undergoing testing at Luke, the night-vision goggle simulator
is fitted to existing F-16 flight simulators. It consists of goggles,
software, a connecting cable to the flight simulator and cranial
movement tracker to record a pilot’s helmet motion and to
present the proper visual cues. The simulator goggles have the same
weight and feel as their cockpit counterparts.
The system is designed to work with all three F-16 flight simulators
used at Luke, including the unit training device, re-hosted weapons
system trainer, and the networked training center.
The simulator does a good job of visualizing the night sky, asserted
Beasley, who also serves as program manager for the networked training
center. “If you flip the goggles up and take a look around,
it’s just as if you were flying around at night, as a typical
basic course student does before he goes into night-vision goggles
training.”
The system is aimed at students who are taking their initial night
vision training. During the three to four week course, students
fly five training sorties where they practice night formation flying
as wingmen. Previously, there was only one night vision simulator—a
simple system that only taught them how to don and remove goggles
in a dark cockpit.
But actually flying with goggles is an acquired habit. Their most
dangerous idiosyncrasies are a lack of peripheral vision and a circular
field of view that is limited to only 40 degrees. “You don’t
have any depth perception,” said Beasley. “A light three
miles away and a light 50 miles away looks the same through goggles.
It’s harder to fly formation and figure out how far away you
are from the other planes.”
Those visual miscues mean pilots must be taught to rely on instrument
crosscheck, which mandates constantly scanning their instruments
and trusting the data even when their senses tell them otherwise.
Johnson, who has used the simulator extensively, said the system
greatly helps teach this vital skill.
“What it does best is take away your peripheral vision,”
Johnson said. “Normally, in the daytime, your peripheral vision
sees the horizon and it automatically knows which way is up. When
you put the goggles on, it takes that away. Now it’s like
you’re looking through a soda straw. And to take all that
information into your brain, you have to move your head around quite
a bit. It takes students a few rides to get the hang of it.”
Night-vision flight trainees must have a safety pilot with them
in case they get disoriented during flight. The simulator enables
them to practice more safely and cheaply. “The biggest benefit
of the sim is to develop that instrument cross check on the ground
when you’re not burning time and gas,” Johnson said.
“When you get the student in the air, his cross check is a
lot more efficient.”
Proficiency in using night-vision goggles is no luxury. They have
become a routine part of night flights, used during most operations
except for take off, landing and aerial refueling. Fortunately,
the simulator can accommodate both air-to-air and air-to-ground
training. “You can get guys in your [simulated] radar scope,”
Beasley said. “As you get closer, you can start to see them
through the goggles in the simulator.”
Beasley said the simulator could actually do a few things that
real flight training can’t. For example, students in a real
night flight will only have a chance to experience using goggles
with whatever phase the moon is in that week. The simulator allows
instructors to vary the moonlight.
The instructors make clear that simulator training is no substitute
for actual flight time with a pair of goggles over your eyes. The
simulator isn’t a perfect imitation. It doesn’t fully
reflect the motion of actual flight. Nor does it show the dense
air traffic of airliners and small aircraft that are encountered
in real airspace.
Perhaps the biggest flaw is that it lacks the processing power
to perfectly simulate lighting for goggles that magnify light 8,000
times. “It would take a huge amount of processing power to
show that and the shadowing effects 100 percent,” Beasley
said. But perfection isn’t needed. The simulator just needs
to be good enough to instill students with the proper procedures
for using night vision devices, added Beasley.
The simulator’s 2-D graphics and 3-D imagery are powered
by Onyx computers from Silicon Graphics. The computers create effects
that are reflective (terrain illuminated by moonlight and starlight),
emissive (lights, flares and explosions) and 2-D head-up display
graphics as seen through goggles, said Brad Morrow, a Silicon Graphics
account manager. These three outputs are blended by SensorHost postprocessors
from the Air Force Research Lab, which adjusts their relative brightness
and also the overall brightness of the scene.