NEW YORK -- As Eastern Air Lines Flight 915 lumbered through the drizzle at Kennedy Airport during take-off for the Dominican Republic, danger loomed.

Unbeknownst to the crew and passengers aboard the flight two years ago, Eastern supervisors at JFK, workers say, had told mechanics to skip crucial safety maintenance on the jetliner, maintenance the law required.

Their reasons: merit raises for getting planes out on time, and pressure from management to slash costs.

Flight 915 left on schedule, but its cockpit equipment, including the radar, the Eastern workers say, had not undergone mandatory checks for glitches. The engines and landing gear had not been serviced, nor had the wing flaps been greased to make the aircraft easier to control.

To cover it up, the managers allegedly fudged maintenance records the night before to make it appear the work had been done, in case the Federal Aviation Administration asked.

The flight arrived safely.

But two years later, Eastern and nine of its managers face criminal charges on a slew of aircraft-maintenance violations -- similar to those of Flight 915 -- that allegedly occurred between July 1985 and March 1989 at Kennedy and LaGuardia airports and at the airline's biggest hub, Atlanta's Hartsfield Airport.

The charges, as well as interviews with several former and striking Eastern employees who blew the whistle on the carrier, paint a disturbing picture of how an airline allegedly shirked safety regulations and endangered passengers' lives, all while the FAA apparently failed to crack down.

The FAA repeatedly was called in to inspect Eastern over the last three years. And the agency slapped Eastern with $12 million in fines since 1987 -- making it the most heavily fined airline in the United States -- then declared the carrier safe and in compliance with regulations when in fact, the indictment charges, it was not.

It was during the last several years, according to the Brooklyn U.S. Attorney's office -- which conducted the year-long grand jury probe of Eastern that resulted in the charges -- that the airline's management executed its conspiracy to bypass crucial safety procedures.

Eastern insists the alleged maintenance scam is ''ancient history'' and has nothing to do with today's Eastern, which is in the midst of a 17-month-old bankruptcy saga and strike and is desperately trying to rebuild its operations.

All the defendants either have been put on administrative leave or have left Eastern entirely. But more than half of them were working at Eastern until two weeks ago, many in maintenance.

Concerned over what appears to have been lax enforcement, the inspector general's office of the Transportation Department is investigating how the FAA handled its probes of Eastern since 1987 and why it failed to detect maintenance violations and pronounced the airline safe, an FAA source says.

The Justice Department is believed to be referring information to the DOT, the source says. DOT spokesman Bob Marx says that since earlier this year, the inspector general has been ''looking into the procedures of how the FAA investigated Eastern.'' But Marx stresses it is not a criminal probe, and it is unclear when it will be wrapped up.

Besides being understaffed at a time when there are more commercial aircraft operating in the country than ever, many of them geriatric, the FAA appears to have turned the other cheek when inspecting Eastern.

According to one FAA inspector, who requested anonymity, some of the agency's officials simply relied on Eastern managers as their sole source in trying to determine whether the carrier was violating safety maintenance procedures.

''It was like asking someone to slash their own throat,'' said the inspector. ''It was a matter of laziness and time that resulted in this slipshod inspecting. ... The inspectors were also naive and couldn't imagine an airline would play around with safety.''