A two-year study by the US National Transportation Safety Board reveals that a target group of light general aviation aircraft with digital "glass cockpits" had twice the fatal accident rate compared with aircraft with traditional cockpits using "steam gauge" analogue instruments, prompting calls for better training and error reporting.
To test underlying the notion that glass cockpits inherently increase safety, investigators tracked from 2002-07 the safety record of 8,364 single-engined piston aircraft built between 2002 and 2006. Over the same period, the NTSB says new aircraft built by manufacturers such as Cessna, Diamond, Hawker Beechcraft, Mooney and Piper were increasingly equipped with glass cockpits, with 90% of those delivered in 2006 having the advanced avionics.
In total, the NTSB target group, consisting of 5,516 glass cockpit aircraft and 2,848 conventionally equipped aircraft, experienced 266 accidents. While the glass cockpit aircraft experienced a lower accident rate compared to conventional aircraft, the rate of fatal accidents per 100,000 flight hours for the group during the study timeframe was more than twice its counterpart.
Despite a relatively short observation period and mission differences - the glass cockpit crashes were typically linked to instrument flight rules business or personal flights while conventional cockpit crashes were more likely to be used in training - the NTSB says it believes the data is "representative of a true effect", meaning that there had been no "significant improvement" in safety with the glass cockpits.
It has made six recommendations to the Federal Aviation Administration to address the problem. These include the revision of knowledge tests for pilots to include glass cockpit operations and malfunctions; development and publication of guidance for a new breed of low-cost glass cockpit simulators; and increasing awareness of voluntary service difficulty reporting of equipment malfunctions.
Key presentations at the hearing are included below.