Age Alone May Not be Best Measurement for Determining Mandatory Retirement for Pilots.

STANFORD, Calif.--(BUSINESS WIRE)--July 21, 1999--

Older pilots do not seem to perform as well as their younger counterparts on simulated flight tests, according to a collaborative study by Stanford University and the federal government.

But the study of 100 older aviators suggests that other factors as yet unknown might be a better gauge of pilot safety than age alone.

The pilots -- experienced amateurs, aged 50 to 69 -- were monitored during a 75-minute flight in a training simulator that tested such things as emergency maneuver performance and general cockpit judgement.

"Overall, we find a significant correlation between increasing age and decreasing performance on a flight simulator, but there is wide individual variation -- some older pilots perform well.

"Therefore, it behooves us to identify better screening methods of pilot safety than the crude and arbitrary measure of age alone," said Jerome Yesavage, MD, professor of psychiatry and behavioral sciences at Stanford University School of Medicine and director of the Mental Illness Research Educational and Clinical Center (MIRECC) at the Palo Alto Veterans Affairs Health Care System.

"We may be best served by measuring pilots' health status, including mental function, medication use -- and, as they become available and reliable, genetic tests to measure the likelihood of the pilot developing performance-reducing conditions such as Alzheimer's disease," he said.

Yesavage, a licensed commercial pilot, says he undertook the study because of a controversial Federal Aviation Administration (FAA) rule requiring pilots to retire from commercial airline service at age 60. The current study, the first large-scale performance review of older pilots, appears in the July issue of the Journal of the American Geriatrics Society.

Statistically, age alone accounted for only 18 percent of the variation in performance. "Obviously, other factors are more important -- that is, they account for more than 80 percent of the variability of performance among pilots, and we need to determine how to measure them more accurately," Yesavage said.

Yesavage also noted that older aviators have more experience, which brings added value to commercial pilots who head a crew.

The pilots tested in the study represented a wide demographic area and varied health status -- though each participant fell within the range considered acceptable to hold a private pilot's license.

Commercial pilots were excluded from the study since FAA retirement rules would have eliminated their representation in the study's upper age group.

Yesavage said his study was limited because it measured a group of pilots at a single point in time instead of comparing changes in specific individuals over time. But he said he plans to conduct a follow-up study that will look at when individual skills begin to deteriorate.

"Until we do that, we can't be sure that some younger pilots reflect higher skills simply because they received more advanced and modern training," Yesavage said.

Moreover, "We have no reason to suspect that age 60 is a particularly relevant benchmark after which pilot skills become unacceptable for whatever reason," he added. "If we were drafting new regulations, there is little to suggest that a younger or older age than 60 is more fair or realistic."

The National Institute on Aging and the Medical Research Service of the Department of Veterans Affairs supported the research. Yesavage's co-authors include Joy L. Taylor, PhD, assistant director of MIRECC's dementia program; Martin S. Mumenthaler, PhD, research associate at Stanford; Art Noda, data base manager at Stanford's Aging Clinical Research Center; and Ruth O'Hara, PhD, senior research associate at Stanford.

The simulator used in the study, a Frasca 141, has been approved for flight training and skill monitoring by the FAA.