Many questions remain after a deadly mid-air collision between a passenger jet landing at Reagan National Airport and a military Black Hawk helicopter occurred Wednesday night.

Scripps News spoke with aviation expert and consultant Kit Darby who has over 30 years of experience in the field.

“There’s technology in the cockpit of the airliner and probably in the helicopter that would normally alert them to this,” Darby said.

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“I’ve flown into that airport. I've flown military airplanes in that airspace. It is complicated,” Darby explained. “But the procedures, when followed, work and the most basic procedure for any pilot is ‘see and avoid.’”

Another thing that stood out from the investigation into what happened so far is Defense Secretary Pete Hegseth’s statement that the three soldiers on board the helicopter were equipped with night-vision goggles.

Darby said night-vision goggles cut off the normal field of vision and are like looking through binoculars and only seeing things in black and white.

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Aircraft do have blind spots, one of which, according to Darby, would be right below them.

“The technology, which is supposed to show him where [another aircraft] is at and even tell him to maneuver away from it, is disabled, I believe below 360 feet and this helicopter was at or below that altitude so it probably wasn't showing up on the technology in the cockpit called TCAS [Traffic Alert and Collision Avoidance System] which would show the target and direct the pilot of the airliner to move away if there was a predicted intersection or crash,” Darby said.

He also said that the TCAS technology should have alerted the pilots of another aircraft whether or not they could physically see it.