Updates with written testimony seen by Reuters in paragraphs 1-2, 7

By David Shepardson

WASHINGTON, Dec 15 (Reuters) - The Federal Aviation Administration is taking action after a collision between an American Airlines AAL.O regional jet and an Army helicopter that killed 67 people in January exposed flaws in safety oversight, the agency's head will tell Congress on Tuesday.

"The DCA (Reagan Washington National Airport) accident was a defining moment for the FAA and for the country. It exposed gaps, but it also galvanized action," FAA Administrator Bryan Bedford will say in written testimony seen by Reuters for a House aviation subcommittee hearing.

Bedford said on Monday that as part of "Flight Plan 2026" the FAA would open a new aviation safety office as part of a strategic plan to improve hiring and training and to identify potential hazards after harsh criticism for failing to address near-miss incidents.

"To accomplish this, we will establish a Safety Integration Office, develop safety risk heat maps, increase transparency, and improve accountability across all levels of the organization," Bedford said in a note to employees.

He said the plan would create an FAA safety management system and implement an FAA-wide safety risk management process.

The system "will help the FAA detect, analyze, and mitigate risk more consistently and ensure that lessons from accidents, incidents, and near misses are acted upon quickly and across the agency," Bedford will tell Congress.

Bedford said the FAA would continue to maintain oversight of aerospace manufacturers, including Boeing BA.N. In October, he agreed to let Boeing hike 737 MAX production to 42 planes per month, removing a cap put in place last year after a mid-air panel blowout on an Alaska Airlines flight.

The FAA also is beginning the process of moving its headquarters into a building that houses the U.S. Transportation Department.

The FAA plans to establish a pilot program for aircraft certification applicants to participate in digitized certification processes.

Transportation Secretary Sean Duffy harshly criticized the FAA for failing to act despite dozens of near-miss incidents before the fatal crash on January 29, just days after U.S. President Donald Trump returned to office.

"We had 84 near misses in the three years before in the D.C. airspace, and no one did anything," Duffy said. "Someone was asleep at the wheel. Someone should have seen that."

Lawmakers from both parties have questioned why the FAA failed to act for years to address close calls involving helicopters near Reagan airport.

National Transportation Safety Board Chair Jennifer Homendy said in August the FAA had ignored warnings about serious safety issues.

Bedford, who took office in July, is overseeing a $12.5 billion rehabilitation of U.S. air traffic control and Duffy wants another $19 billion to complete the job.

The FAA in early May barred the Army from helicopter flights around the Pentagon after a May 1 close call that forced two civilian planes to abort landings. In April, the FAA imposed new restrictions to prevent collisions between helicopters and passenger planes around the busy Harry Reid International Airport in Las Vegas and it has expanded buffer zones at Washington, D.C.-area airports.

"These assessments revealed operational patterns in several locations that needed attention, and we are diligently working to address them," Bedford will tell Congress.

(Reporting by David Shepardson in Washington; Editing by Chris Reese and Jamie Freed)

((Email David.Shepardson@thomsonreuters.com 202-579-6093))