The National Transportation and Safety Board (NTSB) has concluded that the separation distances allowed between helicopter and airplane traffic on Route 4, where an Army helicopter and a commercial passenger jet collided midair on January 29, near Washington, pose an “intolerable risk to aviation safety,” according to a preliminary investigation report released on Tuesday.
In response to this finding, the NTSB is recommending that helicopter flights be immediately prohibited along Route 4 between Hains Point and the Wilson Bridge along the Potomac River during the landing or takeoff of planes on runways 15 and 33 at Ronald Reagan Washington National Airport (DCA). Additionally, the board suggests an alternative helicopter route for that segment of Route 4 when it is not open for rotary-wing traffic.
The on-scene investigation of the collision—which involved an American Airlines flight from Wichita, Kansas, and a UH-60 Black Hawk—was concluded on February 14. Upon collision, the fuselage of the commercial jet broke apart into three pieces and was found inverted in waist-deep water in the Potomac. The helicopter wreckage was located nearby. Tragically, all 64 people aboard the passenger jet, along with three Army crew members—Chief Warrant Officer 2 Andrew Loyd Eaves, Captain Rebecca M. Lobach, and Staff Sergeant Ryan Austin O’Hara—were killed.
Jennifer Homendy, Chair of the NTSB, stated that while the preliminary report details the events of the crash, it does not yet explain how or why it occurred. The investigation is ongoing, involving reviews of airport operations and prior incidents, including near midair collision events.
From 2011 to 2024, data shows that a vast majority of reported incidents occurred during approach to landing. Initial analysis indicated that a Traffic Alert and Collision Avoidance System (TCAS) Resolution Advisory was triggered at least once a month at DCA due to the proximity of helicopters. Unlike standard traffic advisories issued when an aircraft is about 20 seconds away, TCAS resolution advisories indicate a collision threat requiring immediate action.
According to the NTSB, over half of the encounters from 2011 to 2024 saw helicopters flying above the route altitude restriction, which is capped at 200 feet. Two-thirds of these events occurred at night. During the period from October 2021 to December 2024, there were 944,179 commercial operations at DCA with 15,214 “close proximity events” involving commercial planes and helicopters, where lateral separations were less than one nautical mile and vertical separations less than 400 feet. Among these, 85 incidents involved very close calls, with lateral separations of less than 1,500 feet and vertical separations of less than 200 feet.
The NTSB determined that the Black Hawk was not adhering to the limited airspace regulations near DCA. At a maximum altitude of 200 feet, a helicopter operating over the Potomac River would only have a vertical separation of 75 feet from an airplane approaching runway 33.
Following the accident, U.S. Department of Transportation Secretary Sean Duffy immediately restricted helicopter traffic over the Potomac River at DCA until March 31. As the deadline approaches, concerns remain regarding the potential for future midair collisions at DCA, which is why the board is advocating for a permanent solution.
While the recommendation to close Route 4 between Hains Point and the Wilson Bridge when runways 15 and 33 are in use may restrict essential aviation activities for Coast Guard patrols, law enforcement, and government operations, it aims to enhance safety. Moreover, requiring controllers to reroute helicopters could add workload and increase risks.
Homendy noted that although the preliminary report is out, the NTSB has significant work ahead, including simulations, visibility studies, and further interviews regarding helicopter operations and air traffic control. When questioned about whether the resulting crash should be classified as an oversight, Homendy implied that it was more serious, emphasizing that the data from a voluntary safety reporting system was not utilized by the FAA, leading to the unfortunate loss of lives.
