BOB O’QUINN
BETTER PILOT / SAFETY WIRE
Conventional or Glass?
Comparing the safety benefits and challenges
WITHIN A SHORT AMOUNT of time, GA light aircraft cockpit instrumentation has transitioned from conventional round gauges to
digital displays of integrated systems, often referred to as “glass
cockpits.” In GA aircraft, these glass cockpits first appeared in
experimental aircraft. In 2003, Cirrus Design Corporation began
incorporating glass cockpits and soon was followed by Cessna
Aircraft Company, Piper Aircraft, Mooney and Hawker
Beechcraft, Diamond, and Lancair/Columbia. By 2006, 92 percent of new piston-powered light aircraft were equipped with full
glass cockpit displays.
Along with the advanced technology came new concerns of
potential safety with: 1) equipment design and operation; 2) pilot
performance and training; and 3) new accident investigation
techniques. The NTSB addressed these issues when it published
its Safety Study titled “Introduction of Glass
Cockpit Avionics into Light Aircraft.” The study involved sin-
gle-engine-aircraft accident reports for 2002 through 2008.
Statistically, there was a difference in the manner in which
each aircraft type was used, according to the NTSB. Aircraft with
glass cockpits, for example, are more likely to fly longer flights
(median of 96 nm) and more hours in actual instrument meteorological conditions (IMC). Conversely, aircraft with conventional
instrumentation are flown more hours per year, but generally
they fly much shorter flights ( 25 nm) and are more likely to be
associated with instructional flights, resulting in far more takeoff
and landings.
92 percent of new piston-powered GA aircraft
in 2006 were equipped with glass panels
The generalized pilot training to interpret and
operate conventional analog instruments enables
a relatively simple transition from one manufacturer’s products to most any other. Initial training
for any glass cockpit design is far more extensive
and must be equipment-specific. For pilots to
transition from one manufacturer’s design to the
next requires significantly more effort and, once
again, equipment-specific training.
For flight instructors and pilot examiners,
the biggest challenge is the difficulty or inability to simulate and diagnose various system
failures and malfunctions. Such restrictions
limit their ability to train or evaluate pilots’
responses to various emergencies or equipment
malfunctions.
Although the FAA has no specific training
requirements for pilots flying aircraft equipped
with avionics displays, aviation insurance providers often require pilots to complete training
tailored to the individual pilot and aircraft/
glass cockpit to receive and maintain coverage.
Accident investigation techniques are bene-
fiting from the glass cockpit displays that
include recording capabilities. Being able to
more accurately and quickly identify accident
causes helps the GA community improve equip-
ment reliability, safety, and efficiency of aircraft
operations through data analysis. Despite better
information potential, the NTSB advised there
is a need to improve the reporting of malfunc-
tions and defects associated with electronic
primary flight, navigation, and control systems.
Integrated electronic displays have the
potential to increase the safety of GA aircraft
operations by providing pilots with more operational and safety-related information and
functionality. As aircraft equipment becomes
more complex, the demands placed on pilots to
manage and monitor equipment operation will
continue to increase. However, the burden of
responsibility falls on pilots to operate the
equipment safely and efficiently.
Robert O’Quinn, EAA 742434, is a certificated flight
instructor and advanced ground instructor whose primary
aviation focus is on tailwheel training. To view a copy of the
NTSB report, visit www.SportAviation.org.
