Three days of investigative hearings on the deadly midair collision over Washington in January begin Wednesday and aim to reveal new insights into what caused the crash between a passenger plane and an Army helicopter that killed 67 people.

The National Transportation Safety Board will question witnesses and investigators about how the actions of the Federal Aviation Administration and its air traffic controllers and the Army may have contributed to the nation's deadliest plane crash since November 2001. It's likely too early for the board to identify the cause of the crash.

The American Airlines plane from Wichita, Kansas collided with a Black Hawk helicopter while coming into land at Ronald Reagan National Airport and was the first in a string of crashes and near misses this year that have alarmed officials and the travelling public, despite statistics that still show flying remains the safest form of transportation.

Investigations have already shown the FAA failed to recognize a troubling history of 85 near misses around Reagan airport in the years before the collision, and that the Army's helicopters routinely flew around the nation's capitol with a key piece of locating equipment, known as ADS-B Out, turned off.

Aviation attorney Bob Clifford, who is working to file one of the first lawsuits against the government next month, said he hopes NTSB will look beyond the immediate factors that caused this crash to highlight the bigger ongoing concerns in the crowded Washington airspace.

"In this particular instance, there's a much broader picture. And that is the known problems that were being ignored about an unsafe environment for the commercial aircraft to be navigating with the military aviation helicopters in the area," Clifford said.

Even though the final NTSB report won't be released until sometime next year, U.S. Sen. Ted Cruz isn't waiting to propose changes. He introduced legislation Tuesday that would require all aircraft operators to use both forms of ADS-B, or Automatic Dependent Surveillance Broadcast, the technology to broadcast aircraft location data to other planes and air traffic controllers. Most aircraft today are equipped with ADS-B Out equipment but the airlines would have to add the more comprehensive ADS-B In technology to their planes.

"There cannot be a double standard in aviation safety," Cruz said. "We should not tolerate special exceptions for military training flights, operating in congested air space."

The legislation would revoke an exemption on ADS-B transmission requests for Department of Defense aircrafts. It also would require the FAA to evaluate helicopter routes near airports and require the Army Inspector General to review the Army's aviation safety practices.

NTSB Chairwoman Jennifer Homendy said her agency has been recommending that move for decades after several other crashes.

"In 2008, we sent a letter to FAA stating the board believes that the equipage of aircraft with ADS-B In capability will provide -- and I want to stress this -- an immediate and substantial contribution to safety, especially during operations in and around airports," she said.

Transportation Secretary Sean Duffy said that while he'd like to discuss "a few tweaks," the legislation is "the right approach." He also suggested that the previous administration "was asleep at the wheel" amid dozens of near-misses in the airspace around Washington's airspace.

"In the past, people became complacent -- leaders became complacent" Duffy said.

Homendy said the hearings over the next few days will be a "fact-finding proceeding." In addition, the NTSB will also post thousands of pages of evidence from the crash investigation online Wednesday morning.

FAA Administrator Bryan Bedford said that he expects "we're going to have some very uncomfortable conversations over the next two and a half days" but that "they need to be had in the clear light of day - and simply put the best interest of the traveling public ahead of any of our personal interests, perhaps."

The hearings in Washington will involve NTSB board members, investigators and witnesses for organizations involved in the crash. Panels will focus on military helicopter routes in the Washington area, collision avoidance technology and training for air traffic controllers at Ronald Reagan National Airport, among other subjects.

Federal officials have also raised concerns over the nation's outdated. and understaffed air traffic control system. During January's mid-air crash above Washington, one controller was handing both commercial airline and helicopter traffic at the busy airport.

Duffy has announced a multi-billion-dollar plan to overhaul the system controllers use that relies on old technology like floppy disks.

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Associated Press writers Leah Askarinam, Ben Finley and Rio Yamat contributed to this story.