D.C Plane Crash Investigation Explained: All the Answers to Your Key Questions

• Data from the black boxes will help authorities create a "detailed timeline" of how an American Airlines jet and an Army helicopter collided on Jan. 29, killing 67 people

• A few key details and questions have emerged about the helicopter's actions before slamming into the plane

• Government officials have vowed to "get to the bottom" of what went wrong
  

With black boxes in hand, investigators are now focusing on the actions of American Airlines Flight 5342 and an Army helicopter before they collided last week over the Potomac River in Washington, D.C., killing 67 people in a historic disaster.

The National Transportation Safety Board said that the data from both crafts – pulled from what’s known as their flight data and cockpit voice recorders — as well as radar records and the communications from air traffic controllers will allow for a “detailed timeline” of how the crash unfolded late on Jan. 29, just outside Ronald Reagan Washington National Airport.

“Imagine you had two cars that crashed at an intersection, and they had cameras on,” says Laurie Garrow, an aviation expert at the Georgia Institute of Technology. “With the recorders, they’re trying to reconstruct second by second where things were happening.”

At the same time, a few key details and questions have emerged:

The helicopter was flying far too high during a routine night mission and had been twice warned about the jet, which was instructed just a few minutes before landing to switch runways.

Air traffic control staffing levels were also reportedly lower than they normally would have been. And at the last second, the passenger plane pulled up — as though trying to avert catastrophe.

Here are the latest questions and answers as the investigation continues.

What will the black boxes show?

Divers pulled the plane’s cockpit voice recorder and flight data recorder from the wreckage in the Potomac on Jan. 30, NTSB officials have said.

The next day, the NTSB confirmed the Army helicopter’s black box, which combined both functions, had also been located.

The plane’s cockpit recorder covers about two hours of audio, beginning mid-flight; while the flight data recorder captured the entire journey, according to the NTSB.

The flight data recorder includes more technical information about the trip, like the altitude, speed and even more granular details like the position of the wing flaps.

“With the data retrieved from the [flight data recorder], the Safety Board can generate a computer animated video reconstruction of the flight,” the NTSB’s website explains. “The investigator can then visualize the airplane's attitude, instrument readings, power settings and other characteristics of the flight. This animation enables the investigating team to visualize the last moments of the flight before the accident.”

Officials have said they are confident they will be able to get information out of all three black boxes, though they are dealing with some “water intrusion” into the devices — which isn’t unusual — and also having to “synchronize” the data to create a timeline of events.

Full details from what black boxes recorded have not been publicly released.

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What is the NTSB looking for?

As the NTSB continues to parse information from the black boxes, which should include audio of what was said by both crews, authorities are also looking into the maintenance, training and crew history for American Eagle Flight 5342 (operated by a subsidiary of American Airlines) and the Sikorsky UH-60 Black Hawk helicopter that was carrying three soldiers at the time of the collision.

Officials are “building several day histories for both flight crews to include their daily activities,” the NTSB said in a statement on Monday, Feb. 3.

In addition, “The Air Traffic Control group has completed interviews of all five staffed positions in the tower.”

In analyzing the debris field, officials will “be able to determine exactly where the helicopter hit the airplane,” says Capt. Mike Coffield, CEO of KM Cargo.

The recovery and examination of the wreckage from both the plane and helicopter is ongoing as of Wednesday, Feb. 5, the NTSB said.

What did the air traffic controller say?

NTSB officials previously said that while the controllers were giving their “full cooperation,” the interviews themselves were emotionally taxing.

“This is a controller's worst nightmare,” NTSB member Todd Inman told reporters on Saturday, Feb. 1. “It hits everyone that works in that cab and knows them very hard. These interviews take a long time, not because there is that much talking, but there are several breaks that occur for emotions, just to be able to compose themselves, to talk about what happened.”

“We want to be thorough,” Inman said then. “If we need to go back for additional information, we absolutely will.”

Inman also said on Saturday that air traffic control twice alerted the helicopter to the larger passenger jet, including about two minutes before the collision, when the helicopter was told that the plane would be landing at Runway 33.

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The New York Times reported last week that, according to a preliminary report from the Federal Aviation Administration, staffing in the control tower was “not normal for the time of day and volume of traffic.”

One controller was handling both plane and helicopter traffic, rather than two people dividing the job, because someone left early, according to the Times.

Inman confirmed on Saturday that one controller was handling helicopters, “fixed-wing” aircraft, arrivals, departures “and the use of the runway.”

There was also a “ground controller which was handling all aircraft and vehicles not on the runway,” Inman said. “In addition, there was a local assist controller. This person is responsible for assisting the local controller in any type of actions that are needed, reviewing data, scanning the field, a multitude of different things.”

And there was an operations supervisor and a supervisor in training — or five people total — Inman said.

The helicopter was flying far too high: Why?

Beyond a potential staffing issue, officials have acknowledged the helicopter was flying far too high at the time of the crash.

Data indicates the smaller craft was at around 300-350 feet in the air when it hit the larger passenger jet, even though it should have stayed at lower than 200 feet.

Helicopters and planes often fly in close proximity around Reagan — which is one element of the airport’s notorious congestion. That practice has been largely halted in the wake of the collision.

According to outside experts, a key question is why the Black Hawk would have flown so much higher than the 200-foot limit and whether anyone knew where it was in the sky.

“It could have been measurement error or human error,” says Garrow, at Georgia Tech. “That’s what they’re dissecting.”

Defense Secretary Pete Hegseth said as much on Jan. 30 when he told reporters at the White House that “there was some sort of an elevation issue that we have immediately begun investigating …. to get to the bottom of it so that it does not happen again, because it’s absolutely unacceptable.”

“The military does dangerous things, it does routine things, on the regular basis,” he said.

This time, “tragically,” he said, “a mistake was made.”

“It may not have known it was flying higher than it should have been. … it's unclear where and why the two vehicles were where they were at that time, and if it was air traffic,” Garros says.

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Was the helicopter crew wearing night vision goggles?

That’s not clear.

Hegseth said last week that soldiers had night vision goggles with them on what he called an “annual proficiency training flight,” but the NTSB has said they don’t yet know if the goggles were being worn at the time of the collision.

“Those goggles are designed for situations where the only light is moonlight or starlight. If you already have a lot of things moving around and blinking, it could throw things off,” says an active-duty Army helicopter pilot, who did not want to be identified by name. “They could make it harder to see what's going on in the sky.”

Hegseth said the three people on the Black Hawk were a “fairly experienced crew.”

The Army has identified them as Chief Warrant Officer 2 Andrew Loyd Eaves, Staff Sgt. Ryan Austin O’Hara and Capt. Rebecca Lobach.

The last-minute runway switch: Did it matter?

Inman, with the NTSB, has said that the American Airlines plane “made initial contact” with the controllers at Reagan at 8:43 p.m. local time on Jan. 29.

The plane had been prepared to land at Runway 1, but after connecting with the control tower at 8:43 p.m., “the tower controller then asked if the crew could switch to Runway 33, After a brief discussion between the crew, they agreed.”

While such a last-minute switch is “pretty common,” says Garrow, the aviation expert, she added that “if you're not expecting it, it can increase your mental burden coming in.”

Capt. Coffield says that the runway change, on its own, shouldn’t have created a problem as it happens “literally all day long.”

The plane's autopilot ended around 8:45 p.m. and the helicopter was alerted to the plane at 8:46 p.m. and then again, a little less than two minutes later, just before the collision, when the helicopter crew said it would avoid the jet.

The Washington Post reported that Runway 33 is increasingly used by regional aircraft and the planes landing there will often come within “15 feet” of the 200-foot limit at which helicopters fly.

“It can get really sketchy,” helicopter pilot Richard Gallaher told the paper.

Did the helicopter see the wrong plane?

According to the transmissions from between the controller and the Army helicopter, the Black Hawk crew said they saw the jet — and was instructed to go around it — approximately 15 seconds before the collision.

Experts say that suggests the helicopter may have been looking at the wrong craft.

“The airspace at night like that is difficult,” says Coffield, noting that because it was so clear “the lights are shining both on both sides of the river and at the airport.”

“It's one of the most challenging airports in the country, without any doubt,” he also said.

Garrow echoed that: “It does appear that he [the helicopter] thought he had sight on the aircraft, but there were multiple aircraft in the area …. So I don't think he was aware that he was in the flight path.”

The active-duty Army helicopter pilot offered their personal view, telling PEOPLE: "The Black Hawk accepted responsibility for the separation of traffic. That means, they would monitor and address the flight paths themselves. The Black Hawk asked for 'visual separation,' meaning, 'We got this.' "

"It was basically pilot error,” this source believes.

American Airlines plane tried to pull up at the last minute

About 15 seconds after the helicopter was told by the control tower to “pass behind” the plane on Jan. 29, the plane’s crew “had a verbal reaction” and the jet began to “increase its pitch” — meaning it was pulling up into the sky — Inman, with the NTSB, said Saturday.

“Sounds of impact were audible about one second, later, followed by the end of the recording,” he said.

He declined to say more when asked by a reporter if that meant the plane was trying to avoid being hit: “That is something that we will get you more detail on.”

But the experts who spoke with PEOPLE say that data points to the American Airlines crew registering that they were in danger.

“My interpretation …. is that the pilots realized about a second or two before the crash,” Garrow says.

“There was a pitch change, which likely means that they were planning to abort the landing, but there was not enough time, which is my interpretation,” she says.

Inman told reporters that the American Airlines crew also got an automatic warning stating “traffic, traffic, traffic,” which would likely have been from its anti-collision system, though Inman said they were still investigating.

"We're the safest aviation system anywhere in the globe — and it's because of professional pilots and professional aviators and air traffic controllers and maintenance people that work together to keep it that way," says Capt. Coffield.

That important work continues especially in tragedy, he says.

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