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DATA ACQUISTION
Consequently, many of the current EVS sensors,
being designed for the much lower angle of approach
necessary for landing fixed-wing aircraft, are less
effective for the steep landing approaches helicopters
make, he says.
There is also the extra challenge of trying to locate
obstacles on the approach path, such as the fence around
the helipad or other buildings, trees and wires. “These
are things that you don’t have to worry about with fixedwing
AEROSPACETESTINGINTERNATIONAL.COM // JUNE
because the airspace is protected,” he says.
LIGHTING THE WAY AHEAD
For its study the FAA has been working closely with
several manufacturers of EFVS equipment, including
Universal Avionics, recently acquired by the Israelbased
defense firm Elbit Systems, Astronics,
which makes the Max-Viz EVS systems,
Esterline CMC Electronics and Hensoldt,
which was formerly part of the defense division of
Airbus Group.
The suppliers have provided hardware for Johnson
and his team to fit to their test helicopter. Astronics
provided two of its Max-Viz dual-sensor EVS systems.
The systems use both a long-wave infrared (LWIR)
sensor and a visible light camera, which blends with the
LWIR camera to give a clearer picture of the terrain.
“With airports moving to LED lighting on runways and
taxiways LWIR doesn’t pick those lights up as well, so
adding the visible light camera enables our systems to
see those lights,” says Tom Geiger, business unit manager
at Astronics.
As well as providing the technology, says Geiger,
Astronics has worked closely with the FAA “to ensure we
answer any questions relating to the systems themselves,
their installation or use.”
Universal Avionics has provided head-wearable
technology from its ClearVision range as well as
supplementary “pilot training, manuals and ongoing
technical support,” says Tal Golan, Universal Avionics’
rotorcraft business development manager.
Johnson says, “We’re trying to work with industry to
collectively understand what the best technologies for
approaching this are and how to develop performancebased
standards that don’t favour one technology vendor
over another.”
The testing is being conducted on a 40-year-old FAAowned
and operated Sikorsky F-76 A model helicopter.
“It’s essentially a flying laboratory,” says Johnson. “The
helicopter is fitted with at least a dozen video cameras.
There is test equipment in the main cabin where you’d
normally have the seats.
HOW HELICOPTERS USE ENHANCED VISION
Enhanced Vision Systems (EVS) have
been in use for several decades in
aerospace. Elbit Systems, the parent
company of Universal Avionics, has
supplied head-mounted displays to
the defense industry for over 30 years.
Elbit’s subsidiary Kollsman has been
producing EVS sensors to jet-makers like
Gulfstream and Dassault Falcon for the
last 20 years.
Since these systems are used for
obstacle-avoidance, in fixed-wing they
are used during takeoff and landing. But
as Universal Avionics’ rotorcraft business
development manager Tal Golan says,
for helicopters “being near the ground
is a common occurrence. For some it is
where they spend most of the time”.
EVS can therefore be beneficial
during a larger proportion of flight for
helicopters and the aircraft that use EVS
are usually those which do a lot of low
altitude flying and who commonly have
to deal with unexplored, obstacle rich
landing zones.
As well as corporate aviation many
of Astronics’ rotorcraft clients work in
the areas of “fire fighting, search and
rescue, emergency medical services,
oil and natural gas, law enforcement,
news gathering and crop dusting,” says
Astronics’ Tom Geiger.
He says, “These systems help the
pilots see what they may not be able to
see in a variety of conditions: darkness,
haze, smoke, sand, dust and light fog.
They are used in all phases of flight:
takeoff, climb, en-route, approach, and
landing. Seeing clearly helps the pilot fly
more safely.”
3 // Wearable HUDs
display images from the
enhanced vision system
4 // Image from an EVS of
a Challenger business jet
crossing a runway
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