ARLINGTON, Va. (AP) — Divers are expected to return to the Potomac River on Friday as part of the recovery and investigation after a midair collision killed 67 people in the United States' deadliest aviation disaster in almost a quarter century.

Investigators have already recovered the cockpit voice recorder and flight data recorder of the American Airlines plane that collided with an Army helicopter as the plane was landing Wednesday night at Ronald Reagan National Airport next to Washington, D.C. Officials are scrutinizing a range of factors in what National Transportation Safety Board Chairwoman Jennifer Hommendy has called an "all-hands-on-deck event."

All aboard the two aircraft were killed, with officials examining the actions of the military pilot as well as air traffic control after the helicopter apparently flew into the path of the American Airlines jet.

Air crash investigations can take months, and federal investigators told reporters Thursday they would not speculate on the cause.

Authorities were still looking for the helicopter's black box recorder, Defense Secretary Pete Hegseth said Friday on Fox News Channel. Other factors in the crash, including the helicopter’s altitude and whether the crew was using its night vision goggles, are still under investigation, Hegseth said.

At least 28 bodies have been pulled from the Potomac River. The plane carried 60 passengers and four crew members, and three soldiers were aboard the helicopter.

One air traffic controller was responsible for coordinating helicopter traffic and arriving and departing planes when the collision happened, according to a report by the Federal Aviation Administration that was obtained by The Associated Press. Those duties are often divided between two people, but the airport typically combines the roles at 9:30 p.m., once traffic begins to slow down. On Wednesday the tower supervisor directed that they be combined earlier.

“The position configuration was not normal for the time of day and volume of traffic,” the report said.

A person familiar with the matter, however, said the tower staffing that night was at a normal level. The positions are regularly combined when controllers need to step away from the console for breaks, during shift changes or when air traffic is slow, the person said, speaking on the condition of anonymity to discuss internal procedures.

The FAA has long struggled with a shortage of air traffic controllers.

Officials said flight conditions were clear as the jet arrived from Wichita, Kansas, carrying, among others, a group of elite young figure skaters, their parents and coaches, and four union steamfitters from the Washington area.

A top Army aviation official said the crew of the helicopter, a Black Hawk, was “very experienced” and familiar with the congested flying that occurs daily around the city.

“Both pilots had flown this specific route before, at night. This wasn’t something new to either one of them,” said Jonathan Koziol, chief of staff for Army aviation.

The helicopter's maximum allowed altitude at the time was 200 feet (about 60 meters), Koziol said. It was not immediately clear whether it exceeded that limit, but Hegseth said altitude seemed to be a factor in the collision.

Koziol said investigators need to analyze the flight data before making conclusions about altitude.

Flights at Reagan National resumed around midday Thursday.

Wednesday's crash was the deadliest in the U.S. since Nov. 12, 2001, when an American Airlines flight slammed into a residential area of Belle Harbor, New York, just after takeoff from Kennedy Airport, killing all 260 people aboard and five people on the ground.

The last major fatal crash involving a U.S. commercial airline occurred in 2009 near Buffalo, New York. Everyone aboard the Bombardier DHC-8 propeller plane was killed, along with one person on the ground, bringing the total death toll to 50.

Experts often highlight that plane travel is overwhelmingly safe, however. The National Safety Council estimates that Americans have a 1-in-93 chance of dying in a motor vehicle crash, while deaths on airplanes are too rare to calculate the odds. Figures from the Department of Transportation tell a similar story.

But the airspace around Reagan National can challenge even the most experienced pilots no matter how ideal the conditions. They must navigate hundreds of other commercial planes, military aircraft and restricted areas around sensitive sites.

Just over 24 hours before the fatal collision, a different regional jet had to go around for a second chance at landing at Reagan National after it was advised about a military helicopter nearby, according to flight tracking sites and control logs. It landed safely minutes later.

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Gomez Licon reported from Miami. Associated Press writers Zeke Miller, Meg Kinnard, Chris Megerian, Michael Biesecker in Washington; Claudia Lauer in Arlington, Virginia; Brian Melley in London; John Hanna in Wichita, Kansas; and Sarah Brumfield in Cockeysville, Maryland, contributed.

Search efforts are seen around a wreckage site of a deadly midair collision between an American Airlines jet and an Army helicopter, in the Potomac River near Ronald Reagan Washington National Airport, Friday, Jan. 31, 2025, in Arlington, Va., as an American Airlines jet lifts off from the airport. (AP Photo/Alex Brandon)

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In this image provided by the U.S. Coast Guard, wreckage is seen in the Potomac River near Ronald Reagan Washington National Airport, Thursday, Jan. 30, 2025 in Washington. (Petty Officer 2nd Class Taylor Bacon, U.S. Coast Guard via AP)

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In this image provided by the U.S. Coast Guard, wreckage is seen in the Potomac River near Ronald Reagan Washington National Airport, Thursday, Jan. 30, 2025 in Washington. (Petty Officer 2nd Class Taylor Bacon, U.S. Coast Guard via AP)

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National Transportation Safety Board (NTSB) investigators examine cockpit voice recorder and flight data recorder recovered from the American Airlines passenger jet that crashed with an Army helicopter Wednesday night near Washington, D.C, Thursday, Jan.30, 2024. (NTSB via AP)

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Pastor Bob Becker takes part in a prayer vigil in Wichita, Kan., on Thursday, Jan. 30, 2025, for those affected by the crash of American Airlines flight 5342 in Washington the day before. (AP Photo/Travis Heying)

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President Donald Trump speaks in the James Brady Press Briefing Room at the White House, Thursday, Jan. 30, 2025, in Washington. (AP Photo/Alex Brandon)

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Search and rescue efforts are seen around a wreckage site in the Potomac River from Ronald Reagan Washington National Airport, early Thursday morning, Jan. 30, 2025, in Arlington, Va. (AP Photo/Carolyn Kaster)

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Search and rescue efforts are seen around a wreckage site in the Potomac River from Ronald Reagan Washington National Airport, early Thursday morning, Jan. 30, 2025, in Arlington, Va. (AP Photo/Carolyn Kaster)

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A boat works the scene near Ronald Reagan Washington National Airport, Thursday, Jan. 30, 2025, in Arlington, Va. (AP Photo/Alex Brandon)

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National Transportation Safety Board (NTSB) investigators prepare to examine cockpit voice recorder and flight data recorder recovered from the American Airlines passenger jet that crashed with an Army helicopter Wednesday night near Washington, D.C, Thursday, Jan.30, 2024. (NTSB via AP)

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National Transportation Safety Board (NTSB) investigators examine cockpit voice recorder and flight data recorder recovered from the American Airlines passenger jet that crashed with an Army helicopter Wednesday night near Washington, D.C, Thursday, Jan.30, 2024. (NTSB via AP)

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