HUMAN FACTORS
responses to things that need to be avoided,
such as workload bottlenecks on critical
roles,” says Woods.
System designers also have to consider
underloads, when traffic is so light that all of
the tighter aircraft spacing is not needed and
the system can be relaxed so aircraft are not
is such close proximity as they are when
loads are high. Woods says, “The key point is
as we increase automation and as we increase
technology insertion we increase our
dependence on software intensive systems
that are not pristine.
“These are not mechanical systems whose
reliability is fixed, they are changing systems
that are highly interdependent.”
The Boeing 737 MAX design assumed
that if things went wrong with MCAS the
pilots could step in to correct it using a long
established electrical trim system emergency
procedure. In a similar fashion, an ATC
architecture that assumes that machines will
handle things until they are no longer able to
and then people will step in to deal with an
unusual situation, is “bad architecture” in
Woods’s view. This approach will only work
when the rate of surprises and anomalies is
low, not when they can combine and cascade
because of system complexity.
A further challenge is that controllers may
not even get practice in handling smaller
non-normal situations when they are
expected to step into the breach “and handle
the big thing that goes wrong when the
machines can’t really deal with it,” Woods
said. The irony is that they may be blamed
for not saving the day if the 737 MAX
accidents are a guide.
22 AIR TRAFFIC TECHNOLOGY INTERNATIONAL 2020
A growing challenge
The drone industry plans to manage its own
air traffic below 400ft using highly
automated private Unmanned Traffic
Management (UTM) systems tested by
NASA on an experimental level. Drone flight
plans and intentions will be filed with a
private company that will monitor the flight
to make sure it conforms to plan. Any
anomalies during a flight will be reported to
drone operators in the area. Just exactly how
such a system will interact with traditional
air traffic control to keep drones clear of
manned aircraft in the area remains to be
seen. Drone flight demonstrations (see box,
Testing drone traffic integration) are
exploring how a UTM system and traditional
air traffic control should interact.
Then autonomy is another leap forward
from high levels of automation. “We have not
worked out the coordinated, responsive,
flexible, adaptive architecture needed for air
navigation in a world with increasingly
automated parts,” he says.
Whether the industry recognizes it or not
it is dealing with new territory, a new kind of
complex system that requires innovation and
research. “I find that nobody is funding that
kind of work,” Woods says.
“We have been trying to take a leap
forward in air traffic as long as I have worked
in aviation,” he says. But it is difficult to
make incremental changes in the system
alongside new technology designed to enable
the system to handle greater loads. “People
are pushing forward a bunch of changes that
are significant. The question is how do we
make that work coherently, given there will
be brittle points where it needs to be adaptive
and responsive to disruptions.” v
TESTING DRONE TRAFFIC INTEGRATION
An unmanned aircraft system test site in upstate New York is demonstrating the capabilities needed for a
drone to operate airport-to-airport in part to explore the overlap between low altitude drone airspace and
manned airspace above it.
This preliminary test of how Unmanned Tra ic Management (UTM) airspace will relate to traditional Air
Tra ic Management (ATM) is important because communications and visibility between these two is needed
for progress to be made in commercial drone activity. While UTM is intended for airspace below 400ft
in uncontrolled airspace, this will not support all drone activity in the future, according to organizers of the
test program.
The flight operations of a 500 lb maximum takeo weight TigerShark will be conducted by Navmar
Applied Sciences Corporation in the FAA-designated UAS Test Site under the leadership of the Northeast UAS
Airspace Integration Research (NUAIR), a New York-based nonprofit. The drone operators will be in contact
with Syracuse Radar Approach Control. There will be up to three flights from three upstate New York airports:
Gri iss International Airport, Syracuse Hancock Airport and Oswego County Airport. This allows NUAIR to
exercise the full length of the New York UTM corridor.
Researchers are to investigate the interfaces between UTM and ATM in terms of what and how dronerelated
information should be communicated, to ATC and pilots.
The TigerShark drone is being used to research how data about
drone location can be integrated into ATC operations by NUAIR
Photo: NASA