A Fat Finger Could Keep You Grounded

ANN April 1 Special Edition

As airliners have become equipped with more and more press switch devices a problem has been recognized called multi-switching. Multi-switching is when a pilot accidentally presses more than one switch when attempting to complete a system function. After concluding a five-year, multi-million-dollar study of  the problem, the FAA determined the primary cause of multi-switching is an oversized index finger.

An old joke floating around in the 1970s was that because of the proliferation of press-switches in the airline cockpit, Darwin’s theory of evolution dictated that airline pilots would evolve to become all ass and index finger. While the FAA had concluded years prior to the multi-switching problem that all airline pilots are already asses, they now intend to address the index finger by setting a maximum index finger circumference to be measured during an FAA first class medical exam.

The limiting circumference of the index finger has been determined to be 70 mm measured at the center of the finger-nail. This will be determined by placing an FAA approved “Index Finger Test Cup” over the finger; this procedure will be known as the multi-switch finger wave. If the pilot’s index finger exceeds the 70 mm measurement, further testing is required to assure the pilot can demonstrate press-switch accuracy. This will be performed on a keypad with press switches that randomly illuminate for a thirty second time period. The applicant must respond by pressing the randomly illuminated switches with an accuracy rate of no less than 70%.

The multi-switch finger wave test requirement becomes effective April 1, 2015.

FMI: www.faa.gov