A deadly midair collision near Ronald Reagan Washington National Airport has once again raised urgent concerns about aviation safety.
On Wednesday night, a passenger jet and a U.S. Army helicopter collided at a low altitude before crashing into the Potomac River.
Tragically, none of the 60 passengers, which included U.S. and Russian champion figure skaters, or the four crew members on the American Airlines flight AA5342 survived.
The three military personnel aboard the helicopter were also killed.
This disaster comes barely a month after another catastrophic aviation accident in South Korea, where a passenger jet crashed following a suspected bird strike, leaving 179 dead out of 181 people on board.
These incidents have reignited discussions about midair collision prevention and the limitations of existing aviation safety technology.
One technology designed to prevent such disasters is the Traffic Collision Avoidance System (TCAS)—a system that has been in place for decades.
So, why did it fail to prevent this tragedy?
How Does TCAS Work?
A Traffic Collision Avoidance System (TCAS) is a vital onboard safety mechanism that monitors airspace for nearby aircraft and warns pilots of potential collisions.
It relies on transponders—electronic devices that receive and respond to signals from other aircraft.
TCAS operates independently of air traffic control, providing real-time alerts to pilots about nearby aircraft that may pose a threat.
Since its introduction in 1974, TCAS technology has seen major advancements:
- TCAS I: The first-generation system, still in use on many smaller aircraft, provides pilots with a basic “Traffic Advisory” (TA), alerting them to nearby aircraft. However, it does not suggest evasive maneuvers.
- TCAS II: A more advanced system that not only detects nearby aircraft but also provides specific collision-avoidance instructions—such as climbing, descending, or turning. Importantly, TCAS II systems on different aircraft communicate with each other, ensuring that avoidance maneuvers are coordinated.
Under international aviation regulations, all commercial aircraft are required to have TCAS II installed. However, military helicopters are generally exempt from these rules.
Reports indicate that the U.S. Army helicopter involved in this crash may not have been equipped with TCAS, making it invisible to the safety system onboard the American Airlines jet. t
But is the lack of TCAS the sole reason this collision occurred? The answer is more complex.
Why It Struggles at Low Altitudes
Even if both aircraft had fully operational TCAS systems, the technology might still have been ineffective in this scenario.
Why? Because TCAS has a major limitation at low altitudes.
- TCAS relies on radio altimeter data, which becomes less reliable when an aircraft is near the ground.
- At very low altitudes, pilots have limited options to respond to alerts. If a TCAS instructs an aircraft to descend to avoid a collision, but the aircraft is already near the ground, descending is not an option.
- As a safety measure, TCAS systems are designed to limit alerts below 300 meters (1,000 feet) to prevent erroneous or unhelpful instructions.
At the time of the crash:
- The American Airlines flight was at 90 meters (300 feet).
- The military helicopter was at 60 meters (200 feet).
This placed both aircraft in an altitude zone where TCAS warnings are inhibited, potentially rendering the system useless in this situation.
A Disaster Waiting to Happen? Reagan Airport’s History of Near Misses
This is not the first time Reagan National Airport has been the site of a dangerous near-miss.
The airport’s location—situated in a densely populated area with restricted airspace—creates unique challenges for air traffic management.
Commercial flights, military operations, and private aircraft all share limited airspace, increasing the risk of collisions.
In April 2024, a commercial jet narrowly avoided a collision with a helicopter that was just 100 meters (328 feet) below it.
The pilot, who had to take sudden evasive action, later reported:
“We never received a warning of the traffic from air traffic control, so we were unaware it was there.”
This incident sparked concerns among aviation experts and even Democratic Senator Tim Kaine, who opposed plans to increase flights at Reagan National Airport, citing safety risks.
Despite these concerns, lawmakers approved the expansion just a month later.
What Happens Next?
The National Transportation Safety Board (NTSB) has launched an in-depth investigation into this tragedy, focusing on several key factors:
- Why the aircraft failed to avoid each other – Was it due to the lack of a TCAS on the military helicopter? Was air traffic control involved?
- Whether air traffic controllers issued timely warnings – A failure to warn either aircraft could have been a critical factor.
- Reagan National Airport’s airspace congestion – Should regulations be tightened to prevent future collisions?
- Potential new safety measures – Could TCAS technology be improved to provide better alerts at low altitudes?
The findings of this investigation could lead to major changes in aviation safety policies—particularly for airports like Reagan National, where commercial and military flights share highly restricted airspace.
Can Future Collisions Be Prevented?
The tragic loss of 60 passengers and seven crew members in this midair collision highlights serious gaps in aviation safety. ,
While TCAS has saved countless lives, its limitations at low altitudes—combined with exemptions for military aircraft—leave dangerous blind spots in collision prevention.
Should TCAS technology be modified to function at lower altitudes?
Should military aircraft be required to have transponders to communicate with commercial planes?
Should airports like Reagan National impose stricter air traffic controls?
These are the critical questions that regulators, airlines, and safety experts must urgently address.
Because if history has taught us anything, it’s that the next near miss could easily become the next disaster.
