by Paul Bertorelli

For anyone equipped with it—and these days, that’s most of us—GPS is a terrific addition to the cockpit. It’s accurate, reliable and is proving to be an indispensable approach aid. But there’s a dark side to the GPS revolution: the FAA has done a poor job of training controllers to understand how airplanes should fly GPS procedures. Although it’s not universally true, many controllers are clueless in issuing GPS approach clearances and missed approach instructions; their lack of knowledge shows up in the system every day. …