Washington DC plane crash: Aviation expert says 'blind spot' may have caused American Airlines jet, Black Hawk chopper to collide

As the US National Transportation Safety Board (NTSB) begins a probe into the Washington DC plane crash involving an American Airlines plane and a US Army Black Hawk that killed 67 people, an aviation expert suggests that the aircraft could have been in each other’s blind spots when they collided.  

Shawn Pruchnicki, a former airline pilot and an assistant professor at the Center for Aviation Studies at Ohio State University, believes the aircraft couldn't have gotten enough time to manoeuvre around blind spots since they were so close to the ground. 

"Helicopter pilots can’t be just constantly leaning forward or backward, because you could become disoriented," Pruchnicki told NBC News. "So there could have been a visual obstruction for them as they were trying to find this jet, and they ran out of time." 

There were also additional challenges in Reagan National Airport, including skies congested with military aircraft and plenty of light on the ground. "Reagan is just so saturated with lights. It’s very easy to lose sight of an airplane in that flood of lights," he added. 

The NTSB is also focusing on the pilots’ communications with air traffic controllers. It will also investigate whether there were any missteps on the part of pilots, probe the functioning of the automated system that warns the pilots of another aircraft nearby and whether any visual obstructions prevented the pilots from seeing each other.

The initial probe by the Federal Aviation Administration (FAA) had revealed that one controller at the tower was handling both helicopters and aeroplanes, reported NBC News. Though the FAA guidelines allow for this, towers usually have a separate controller who deals with choppers.  The report added that staffing was "not normal for the time of day and volume of traffic."

However, so far it seemed like communication between the aircraft and air traffic controllers was routine. US Transportation Secretary Sean Duffy said both aircraft maintained standard communication with the air traffic control tower when they crashed. 

The investigators will collect reviews of radio traffic and data on aircraft flight paths and communications with air traffic controllers. "We will look at all the humans that were involved in this accident. We will look at the aircraft. We will look at the helicopter. We will look at the environment in which they were operating in. That is standard," NTSB Chair Jennifer Homendy told reporters Thursday.

There are also queries related to the Traffic Alert and Collision Avoidance System (TCAS) that warns pilots about another aircraft on a collision course. While military aircraft are not equipped with this technology, American Airlines did have it. However, the system reduces the number of alerts it issues as a plane descends to avoid false alarms from other aircraft on the ground. The American Eagle’s last recorded altitude was 375 feet and the accident occurred while it was readying to land.