DALLAS -- A former federal aviation regulator says the government isn't doing enough to track down people who may have obtained fraudulent aviation mechanic's certificates a decade ago without taking the required test.

Gabriel D. Bruno, a former Federal Aviation Administration supervisor, told Dallas television station WFAA that the FAA fell short of ensuring the safety of the flying public.

Some of the mechanics who bought FAA certificates from a Central Florida training school now work for aircraft manufacturers and privately owned maintenance shops, WFAA reported.

It said up to 80 of the St. George Aviation students were never retested and that 33 might still be working on aircraft.

As many as 1,800 mechanics were certified at Sanford-based St. George Aviation from October 1995 to January 1999, when federal investigators turned up flawed testing practices, according to Orlando Sentinel archives. Oral and written regimens -- costing up to $855 -- that were supposed to take six or eight hours were sometimes completed in as little as a few minutes. FAA documents reflected inaccurate test times and, sometimes, tests taken on days when the center wasn't even open.

FAA spokesman Roland Herwig said, however, that the agency tracked down the students who got fraudulent certificates.