On Jan. 29, a collision between an American Airlines passenger jet and an Army helicopter at Ronald Reagan Washington National Airport near Washington, D.C., killed 67 people, including more than a dozen figure skaters.

The body of the plane was found upside down in three sections in waist-deep water. The wreckage of the helicopter was also found. At least 28 bodies were pulled from the icy waters of the Potomac River. There was no immediate word on the cause of the collision. 

There are many questions about how the deadly crash could have occurred. Here’s what we can VERIFY. 

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After the collision, some people on social media expressed surprise that a military helicopter was able to fly near a commercial jet in the Washington, D.C., area. 

Is it common for military aircraft and commercial planes to fly near each other around Reagan National Airport?

It’s common for military aircraft and commercial planes to fly near each other around Reagan National Airport. 

There are several military bases in the Washington, D.C., area near Reagan National Airport, including Joint Base Anacostia-Bolling, Andrews Air Force Base and Fort Belvoir. The Pentagon, which is not a military base but houses the U.S. Department of Defense, is also nearby. 

The airport itself is also incredibly busy — servicing more than 25 million passengers a year. The airspace around the airport is complex due to various airspace restrictions that overlap, and it’s often crowded with commercial flights, military planes, helicopters and other aircraft.

The Federal Aviation Administration (FAA) has safety policies in place to prevent midair collisions, according to a 2021 report from the U.S. Government Accountability Office (GAO). 

Within the D.C. area airspace, specifically, the report found that the FAA has established maximum altitude limits for helicopters to ensure the safety of both helicopters and commercial passenger planes. According to FAA policy, helicopters must maintain at least 500 feet of vertical separation from large passenger aircraft while in flight in certain airspace near commercial airports. 

In airspace near Reagan National Airport and the Potomac River, the FAA further limits the maximum altitudes for helicopters where helicopter routes overlap with commercial passenger airplane operations to ensure the safety of all aircraft. As a result, helicopters in these areas may fly as low as 200 feet above mean sea level, the report says. 

Data from American Airlines Flight 5342’s radio transponder show the aircraft were at an altitude of around 400 feet when the crash occurred. Defense Sec. Pete Hegseth said in a video statement that the Army is investigating whether the Black Hawk’s altitude played a role in the crash. 

Some people are wondering how this crash could happen since most airlines have systems in place to avoid midair collisions, while others claim the alert system will deactivate under 1,000 feet.

Do commercial plane crash alert systems operate differently below 1,000 feet?

Commercial plane crash alert systems do operate differently below 1,000 feet.

The Traffic Alert and Collision Avoidance System, known as TCAS, is a safety system that helps prevent mid-air collisions between aircraft by giving pilots visual warnings of approaching aircraft and audio messages advising how to react. 

Under U.S. law, TCAS is mandated for commercial aircraft, including regional airline aircraft with more than 30 seats or a maximum takeoff weight greater than 33,000 pounds. 

There are two ways pilots can receive TCAS alerts: a visual display in the cockpit and an audio message. The FAA says audio alerts are deactivated below 1,000 feet on approach. 

The day after the crash, some people online claimed the Black Hawk helicopter was not equipped with a “black box.” A black box is a data recording device that captures vital information about an aircraft and its flight parameters. It is built to be virtually indestructible.

Did the Black Hawk helicopter involved in the crash not have a “black box”? 

Officials on Thursday said crews are searching for a black box aboard the helicopter. 

On Jan. 30, J. Todd Inman of the National Transportation Safety Board said during a press briefing that the agency has not recovered any of the “black boxes involved yet,” but that investigators “know they’re there.”

“We will probably have more than one black box, so to speak,” Inman said. “It is our understanding that the Sikorsky helicopter is equipped with some form of recording devices and those will be read by either the DOD or by us.” 

A Sikorsky H-60 helicopter is another name for the Black Hawk.

In the hours after the collision, some social media posts suggested that this is the deadliest plane crash in the U.S. since the terrorist attacks on Sept. 11, 2001. 

Was this the deadliest commercial plane crash in the U.S. since 9/11? 

The collision was not the deadliest commercial crash in the U.S. since 9/11, but it was the deadliest in nearly 24 years. 

On Nov. 12, 2001, just a couple of months after the terrorist attack, an American Airlines flight crashed into a residential area of Belle Harbor, New York, just after takeoff from Kennedy Airport, killing all 260 people on board and five people on the ground.  

The Associated Press contributed to this report.