Glass isn’t the Issue
Tuesday, February 28th, 2012
When electronic flight instruments were introduced to GA cockpits there was widespread belief that it could make a difference in safety. There were also fears that poorly trained pilots would be slamming into hillsides on IFR approaches. Neither projection happened exactly the way some expected. The AOPA Foundation’s Air Safety Institute has just completed its third review of technologically advanced aircraft (TAA) and here are a few thoughts for your consideration.
- Glass cockpit aircraft are not falling out of the sky with great regularity in Instrument meteorological conditions (IMC)
- Legacy glass aircraft (Mooney, Piper, Beech, etc.) have a significantly lower fatality rate* than new technology glass aircraft (Cirrus and Cessna Corvalis/Columbia)
- Cross-country new technology glass aircraft do not fare so well in takeoffs, landings, and go-around scenarios.
You noted the asterisk next to the fatality rate. That is our best estimate relative to exposure. The FAA estimates the GA flight activity but doesn’t do it by make and model. To normalize and be able to compare the data we used the number of aircraft delivered and when they were delivered to estimate usage. The study population only includes aircraft built from 1996 and newer, so many of the immobile old warhorses that grace hangars and tie downs are not part of the study. It’s new airplanes compared to new airplanes.
Diamond is conspicuous by its absence. The DA40, as a new technology aircraft, isn’t comparable in usage patterns to the Cirrus or Corvalis. A much smaller engine and cruise speed/altitude envelope put it into a separate category. That said, it had very few accidents but there was so little exposure data that we felt that the statistics would be badly skewed. So, regrettably, it is not included in this sample.
A couple of things stand out: The vast majority of accidents occurred in day VMC conditions where the advantages of full glass instrumentation over analog may not be so great. The new technology aircraft pilots (Cirrus and Cessna Corvalis) apparently are having difficulty with basic airmanship relative to takeoffs, landings, and go-arounds. A couple of possible explanations come to mind.
These aircraft are relatively short, coupled with high wing loading and high power, which means the need for gentle application of power and solid application of rudder. Cirrus accident investigators noted that in almost every case, the wreck was off the left side of the runway (no political comments please). I’ve flown both aircraft and they are not hard to handle but they are different from legacy aircraft in some respects and pilots need to respect that. So, in summary, we come to the conclusion that it is not the aircraft or the instrumentation that seems to be impacting the safety record but how the equipment is used and by whom. It has always been so. However, there are some areas where the new equipment can make a difference and that will not show up so quickly in statistics. I’ll discuss one of them next week.
It must be remembered, however, this looks at the negative side only – accidents. We haven’t come up with a good way to measure increased utility – i.e., are more trips successfully completed by glass aircraft versus non-glass. We’re looking at ways to try to measure that now.




Bruce Landsberg, President of the AOPA Foundation