Major issue Black Hawk pilot may have experienced before crashing into plane leaving 67 dead

Theories have started to emerge around the tragic crash between the Black Hawk helicopter that crashed into a passenger plane in January.

The crash shook the aviation world, which saw mistakes from both parties cost the lives of all 64 passengers and three military personnel involved.

Both aircraft plunged into the Potomac River following the accident, which occurred on 29 January this year, with a lapse of communication being blamed for causing the crash, as it was reported that Captain Rebecca M. Lobach appeared to ignore instructions to change course.

She was responsible for piloting the military aircraft which struck the American Airlines flight moments after it was cleared to land at Ronald Reagan Washington National Airport.

While it was believed that the helicopter was flying too high, new reports say that the pilot did hear the instructions, but failed to execute 'visual separation' successfully.

Visual separation is a common practice for pilots, which involves using their own prerogative to maintain a safe distance from others in the sky while keeping an eye on nearby activity.

But three months on, aviation experts have weighed in with their opinions on what really happened, as the member of a helicopter crew took to Reddit to explain that it might be something to do with Lobach's 'depth perception'.

The user highlighted that it was speculation, but claimed: "I can see how they could have assumed they saw the aircraft the tower told them about and in reality it could have been a different aircraft in the same direction.

"Night time really takes away your depth perception and if they were on NVGs (Night Vision Goggles) depth perception is greatly reduced.

"If they assumed the aircraft they were looking at was the one that tower told them about it's very easy to not see another aircraft approaching that is at the same low altitude as you with all that cultural lighting."

While it may sound like a lot of theorising, it was confirmed by National Transportation Safety Board that the military crew were wearing NVGs.

The wreckage was uncovered from the Potomac River in Washington D.C (ROBERTO SCHMIDT/AFP via Getty Images)

NTSB Chair Jennifer Homendy said in February: "We do believe, given the mission and given what we’ve heard or not heard on the CVR (cockpit voice recorder) that they were wearing night-vision goggles."

If they weren't, Homendy said they would have needed to declare themselves as flying unaided.

However, flying with NVGs comes with its own risks, as explained by Night Flight Concepts.

It reads on the official website that 'flying with NVGs results in no colour vision, limited depth perception, a poor field of view, and lower clarity when compared to our regular eyesight during day VFR operations'.

The explanation further details that the depth sense that we're used to with the naked eye is reduced when wearing NVGs, with pilots still possibly needing distance estimates that use monocular signals.

"Relying on this form of depth perception comes with its own set of concerns," it reads.

"Distance measurement becomes more difficult for humans in this manner, and things seem to be farther away than they really are."

It is believed that Lobach and those onboard the Black Hawk were wearing NVGs (X)

This links to the new report published in the New York Times, which detailed that the pilots failed to successfully carry out 'visual separation'.

It was said that the air traffic controller could be heard telling the pilots that visual separation was 'approved'.

The reasons behind the failure to execute the movement are still unknown, and just 15 seconds later, the chopper collided with the American Airlines plane which was carrying 60 passengers and four crew.

The report by The New York Times further claims: "The Black Hawk was 15 seconds away from crossing paths with the jet. Warrant Officer Eaves then turned his attention to Captain Lobach.

"He told her he believed that air traffic control wanted them to turn left, toward the east river bank.

"Turning left would have opened up more space between the helicopter and Flight 5342, which was heading for Runway 33 at an altitude of roughly 300 feet. She did not turn left."