U.S. airlines must develop stricter internal safety programs and conduct more risk analysis under a new regulation created as a result of the fatal Colgan Air crash almost six years ago.

The final rule published today by the Federal Aviation Administration imposes the latest safety techniques on everything from pilot training to data trend analysis under one sweeping program instead of by piecemeal mandates.

While most of the largest airlines have voluntarily begun the program, known as Safety Management System, the regulations require all carriers operating planes with 10 or more seats to participate.

Read More About the Colgan Crash Legacy:

“This final rule is part of the FAA’s efforts to continuously improve safety in air transportation by filling gaps through improved management practices,” the agency said.

Accidents in U.S. skies have been extremely rare and random events that didn’t lend themselves to prevention by focused new rules, the FAA said.

The new rules require carriers to scour flight records, place observers in the cockpit and encourage employees to come forward with concerns. Once safety issues are identified, the airline must take steps to eliminate them though better training, changes in procedures or improved communication with employees.

The agency identified 123 accidents from 2001 through 2010 that would have been prevented if carriers had been more aggressive about monitoring broad risks.

On Feb. 12, 2009, a regional turboprop plane operated by Colgan Air, then owned by Pinnacle Airlines Corp., crashed near Buffalo, New York, killing all 49 people aboard and one man on the ground. It was the last fatal airline accident involving a U.S.-based passenger airline.

To contact the reporter on this story: Alan Levin in Washington at alevin24@bloomberg.net. To contact the editors responsible for this story: Jon Morgan at jmorgan97@bloomberg.net.

Photo Credit: Southwest pilots in the cockpit. Liz West / Flickr