...But Experience (Maybe) Does Count
Most of the research into aging and accident rates has focused on professional pilots, driven by the debate over the Age-60 Rule, which requires retirement at that age for airline pilots, regardless of physical condition or mental ability. The scant research that has been done on private pilots (or holders of third-class medicals) has been inconclusive and sometimes contradictory. For example, a 1991 study of NTSB records from 1985 and '86 showed that private pilots age 60 and older had accident rates about twice that of pilots age 16 to 59. One problem is that many studies depend on analysis of crash statistics. "The trouble with accident data is that it's relatively rare, and it's difficult to control for all the factors that vary from case to case," Prof. Dan Morrow, of the University of Illinois, told AVweb. Morrow has studied pilots in lab situations, and has found evidence that they can draw on their experience and expertise to cancel out the effects of aging. "We try to develop experiments under controlled circumstances, that look specifically for the impact of age on performance. These results should relate to the real world," he said. Among the research that depend on crash data a 1998 study of NTSB records on 10-seat-or-fewer crashes from 1983-92 found pilots age 60 or older (11 percent of the total) were three times more likely to die, and pilots age 50 to 59 were twice as likely to die, compared to pilots younger than 25 (7 percent of the pilots). Yet a 1994 study of 12 years' data found only "a hint" of an increase in accident rates for pilots over 63 flying with a third-class medical. The CAMI report acknowledges that "research on aviation safety outcomes in relation to age has produced mixed results, with some studies indicating a trend across age and others failing to detect any relationship of age to safety outcomes." In its report last year on data limited to professional pilots, CAMI exhaustively crunched the numbers through about a dozen analytical hoops, and found a pattern of higher accident rates for younger pilots, with accidents declining with age to a relatively stable rate in the middle years, followed by an increase for older pilots over age 60. While pilots and the FAA turn to research for answers, definitive results remain elusive.