More Glass Panel Cockpits in GA Aircraft Have Not Had Safety Impact, Says AOPA Foundation’s Air Safety Institute Report

January 3, 2012

Contact: Benét Wilson
[email protected]

Frederick, MD – The increase in glass panel cockpits in general aviation aircraft has not had a dramatic impact on safety, according to new research by the Aircraft Owners and Pilots Association Foundation’s Air Safety Institute.

Glass panels were introduced first in higher-performance aircraft that are typically used for business and personal travel, and have since become standard in virtually all production aircraft. Recently certified designs, such as the Cirrus SR22, transitioned very quickly to glass panels. Very few new aircraft of any type are delivered with analog gauges.

The accident rate in lower-powered aircraft, with or without glass panels, is higher, but the accidents are less likely to be fatal. “What you have on the panel doesn’t matter nearly as much as what you’re flying and how you’re flying it,” said ASI Manager of Aviation Safety Analysis David Jack Kenny.

The Accident Record of Technologically Advanced Aircraft special report tracked more than 20,000 certified piston aircraft manufactured between 1996 and 2010, a total fleet with roughly equal proportions of glass and analog gauges. The most dramatic differences in the accident record were found among three distinct groups.

One, single-engine fixed-gear models with less than 200 horsepower had the highest accident rates but lowest fatality rates. Two, complex or high-performance models certified before 1980 had a lower accident rate, but the rate of fatal accidents was nearly identical. Three, the accident rate of models certified after 1988 with 200 horsepower or more was more than 20 percent higher than comparable legacy models. The fatal accident rate in the newer models was more than 60 percent higher, in part because these aircraft likely spend comparatively more time flying at night and/or in IMC.

Overall, glass cockpit displays had a “negligible” effect on the accident patterns among similar aircraft, though data suggests they set themselves apart in the traffic pattern. “We consistently see more accidents during takeoffs, landings, and go-arounds in glass panel airplanes,” Kenny said.

The difference is smallest among the low-power models, and the reason for it remains unclear. One possibility is that analog gauges can be more easily interpreted during rapid changes in airspeed and altitude. Pilots with glass panels may also be “spending more time staring at the displays instead of looking outside,” Kenny said. On the other hand, glass panels may have advantages when it comes to terrain avoidance, and avoiding VFR flight into IMC, but “the numbers are small enough to leave doubt about whether this is a real effect,” he added.

Airmanship still matters much more than equipment. “Don’t count on machinery to save you from bad judgment,” Kenny said. Pilots who fly in technologically advanced cockpits should learn them thoroughly because the lack of standardization and model-specific training remains an obstacle. In the days before glass, instrument interpretation skills learned in one aircraft transferred easily to another; there are many variations among glass panel displays. ASI recommends that pilots take time to master the systems, preferably on the ground.