For a few years now, we have been writing about the perfect safety record of commercial airliners in the US operating under Part 121 and the example this sets for uncrewed aviation in the long run. That amazing 16-year run of no major accidents in the National Airspace System (NAS) came to an abrupt end two nights ago.

On Wednesday January 29 at 8:45 PM, American Airlines flight 5342, a regional jet arriving from Wichita, Kansas, collided over the Potomac River, one mile before the Ronald Reagan Washington National Airport (KDCA), with an US Army helicopter, a Black Hawk stationed in a nearby base.

The Canadair Regional Jet 700 (CRJ700) was operated by PSA Airlines, a wholly owned subsidiary of American Eagle. Aircraft flying under the PSA Airlines banner use the codename BlueStreak followed by the flight number, in this case the CRJ was operating under the radio identifier BlueStreak 5342.

VAS Aviation Channel

The military helicopter was operating on a published route “Route 1” and eventually transitioning to “Route 4” after the Reagan airport environment, both routes flying over the eastern shore of the Potomac River. The maximum altitude for Route 1 is 200 ft. AGL and is clearly visible in the published helicopter chart of the area. The transition to “Route 4” then continues at 200 ft AGL until the Wilson Bridge, where it authorizes a climb to 300 ft. AGL, safely away from the approach cone to KDCA. Both Route 1 and Route 4 are visual routes to be flown under Visual Flight Rules or VFR. The helicopter was identified as Priority Air Transport (PAT) and the flight number 25, in other words, PAT25 for all radio communication purposes.

The accident is still under investigation, but one thing is clear: Flight 5342 was following a procedural approach to Reagan National to runway 1 with a “Circle to Land” on Runway 33, a shorter runway used for these types of small jet aircraft, and the helicopter was flying a published helicopter route with an altitude limitation.

At low levels and on clear nights, the lights of aircraft blend in with the city lights, sometimes creating confusion in pilots looking at nearby traffic. For a few seconds, the CRJ700 heading north on the circle to land on runway 33 was in exact opposite direction to the helicopter flying south on published Route 1. This meant that there was no lateral movement on either aircraft and therefore no discernable way to determine if the lights approaching are stationary or not. The only way to guarantee separation is vertically, in other words, one aircraft flying low and the other flying high.

According to the Pentagon, both helicopter pilots were using Night Vision Goggles (NVGs), which enhance night vision but have no peripheral vision or depth perception.

It is important to acknowledge that the military helicopter and the KDCA tower were communicating in a different radio frequency than the tower was using to communicate with the regional jet. In other words, the CRJ700 pilots were not listening to the exchanges between the airport and the military helicopter.

There was another airliner right behind the CRJ700, American Airlines flight 3130 (an Airbus 319) at a slightly higher altitude (2,200 ft.) also heading to the airport for landing. There is a possibility that the helicopter pilots were looking at another aircraft, either the A319 or one taking off from the Reagan airport. Judging by the ATC audio that is already available to the public, the air traffic controller advised the helicopter pilot of the incoming flight, and the helicopter pilot acknowledged its presence and confirmed visual separation.

Actual Air traffic Control (ATC) exchange seconds before the crash:

KDCA Tower on civilian frequency: “BlueStreak 5342, Washington Tower, winds are 320 at 17 gusts 25. Can you take runway 33?”

BlueStreak 5342: “Yeah, we can do 33 for BlueStreak 5342.”

KDCA Tower: “BlueStreak 5342, as you cross the bridge change to runway 33. Runway 33, cleared to land.”

BlueStreak 5342: “Change to runway 33, runway 33, cleared to land; BluesStreak 5342.”

KDCA Tower on military frequency: “PAT25 traffic just south of the Woodrow Bridge, a CRJ, it’s 1,200 ft. setting up for runway 33.”

PAT25: “PAT25 has the traffic in sight, request visual separation.”

KDCA Tower in military frequency: “Visual separation approved.”

A few seconds later, there is an audible warning on the KDCA Tower frequency that alerts of a possible conflict between two aircraft.

KDCA Tower in military frequency: “PAT25 do you have the CRJ in sight?”

PAT 25: “We have the CRJ in sight, request visual separation.”

KDCA Tower: “Pat25 pass behind the CRJ.”

PAT25: “Affirmative.”

Almost immediately, the two aircraft collided in midair at 400 ft. AGL and one mile straight on the final approach cone for runway 33.

Issues that would play a role in the investigation, not listed according to relevance or importance:

  • The fact that both helicopter and regional jet were on different radio frequencies.
  • The helicopter’s published route indicated a maximum altitude of 200 ft. AGL. The accident occurred at 400 ft. AGL.
  • The fact that the pilots of the helicopter were using night vision goggles (NVG), with the loss of peripheral vision and depth perception.
  • The decision to use the “Circle to Land” approach to runway 33 instead of a straight landing on runway 1.
  • The presence of another aircraft on takeoff and one Airbus 319 immediately behind the regional jet.

This accident is the first major commercial airliner, multi-fatality event, since the birth of the uncrewed aviation industry in 2012, so most new members of the aviation community have never witnessed this kind of accident and what will eventually follow. There will be recriminations, misinformation, and plenty of speculation and bad faith assumptions, but the Federal Aviation Administration (FAA) and the National Transportation Safey Board (NTSB) will do their job, promptly and efficiently, and soon we will know exactly what happened.

One important lesson for the uncrewed aviation industry is the reliance on voice commands and pilot’s perceptions to maintain aircraft separation and safety. In this case, both failed the 67 souls that perished in this tragedy.

If we ever intend to integrate drones and air taxis without a pilot on board to the NAS, it will be by using technology that replaces this antiquated and highly unreliable way of maintaining aircraft separation in flight.

The application of a strong Detect and Avoid (DAA) system and the integration of Uncrewed Traffic Management (UTM) to existing ATC is the only way in which we will be able to add uncrewed aircraft to the NAS in a safe manner.

Let us learn, once again, from this accident that the current ATC system has reached a dangerous point of saturation and new technology is needed for both crewed and uncrewed aircraft safety.