15th of February 2025

Update on the 29th of January 2025 midair collision between an American Eagle CRJ-701ER, and a US Army Sikorsky UH-60 Black Hawk helicopter, callsign PAT25.

NTSB news conference on 14th of February 2025 based on preliminary information downloaded from the CVR/FDR from the helicopter.

American Airlines Flight 5342 took off from Wichita Airport, Kansas (ICT) at 17:38 local time (23:38 UTC). Prior to descent, the flight crew briefed the expected arrival procedure (TRUPS FIVE) for an ILS approach to runway 01 at DCA. Descent began at 20:15 ET.

The Black Hawk helicopter, callsign PAT25, was on a combined annual and night vision goggle check-ride for the pilot flying (PF) and the crew was probably wearing night vision goggles throughout the flight.

At 20:30 local time (01:30 UTC), PAT25 began flying north to south over the Potomac River after manoeuvring near Laytonsville, MD. Cockpit voice recorder (CVR) data indicates that the instructor pilot was pilot monitoring (PM) and the check-ride pilot was pilot flying (PF).

At 20:33:41, PAT25 requested the Reagan National Airport (DCA) Tower for helicopter Routes 1 to 4 to Davison Army Airfield (KDAA), which was approved by the controller.

The Washington DC helicopter routes designated by the FAA stipulate maximum altitudes and indicated routes but not lateral boundaries. For the 6.3 nm sector of Routes 1 and 4 between Memorial Bridge and the Woodrow Wilson Bridge, the maximum permitted altitude is 200 ft. Opposite the approach path for aircraft landing on runway 33, Route 4 is depicted over the East side of the Potomac River.  

At 20:38:39, PAT25 reached the intersection of the DC Beltway and the Potomac River near Carderock, MD, began descending and picked-up Route 1 over the river towards downtown Washington, DC.

At 20:39:10, the Potomac Approach controller cleared Flight 5342 for the Mount Vernon visual approach to runway 01. Four minutes later the crew contacted DCA Tower. The controller asked if the crew could switch to runway 33. After a brief discussion between the crew, they agreed to runway 33.

At 20:43:48, PAT25 was 1.1 nautical miles (nm) west of Key Bridge. At this point, the PF had an indicated altitude of 300 ft, while the PM had an indicated altitude of 400 ft. Neither pilot commented on the discrepancy. In this sector of Route 1 the maximum permitted altitude is 700 ft.

At 20:44:41, the CRJ selected flaps 30, then flaps 40. Eight seconds later, 6.2 nm south of the airport, the landing gear was down and locked, with the aircraft fully configured for landing.

At 20:45:27, the CRJ was 5 nm south of the airport, the autopilot was disconnected and the aircraft began a shallow right turn off the path of the runway 01 localizer at a radio altitude of 1700 ft and with an airspeed of 134 knots.

At 20:45:30, PAT25 passed over the Memorial Bridge. The PM told the PF they were at 300 ft and needed to descend, with the PF responding they would descend to 200 ft.

At 20:46:01, the Tower controller called PAT25, advising them that a CRJ was at 1200 feet just south of the Woodrow Wilson Bridge, circling to runway 33. This communication was audible in the CRJ, but the portion stating the traffic was "circling" may not have been heard by the crew of PAT25.

At 20:46:08, PAT25 responded that they had the traffic in sight and requested visual separation, which was approved by the controller.

At 20:46:29, the crew of the CRJ received a 1000 ft automated call-out.

At 20:47:26, the CRJ began to roll left to line-up with runway 33 at 133 knots and two seconds later the crew received a 500 ft automated call-out. According to ADSB data, the airliner would have been about 1.2 nm from the runway 33 threshold at this point.

At 20:47:27, PAT25 passed the southern tip of Hains Point, about 0.9 nm from the point where helicopter Route 4 crosses the extended centreline of runway 33.

At 20:47:39, DCA Tower called PAT25 asking them if they had the CRJ in sight. This was audible in both CVRs. A separation conflict alert was audible in the background of the Tower's transmission.

At 20:47:40, the crew of the CRJ received an automated Traffic Advisory call-out: “Traffic, Traffic”.

At 20:47:42, the Tower instructed PAT25 to pass behind the CRJ. This was audible in the CRJ’s CVR but the portion of the transmission stating "pass behind the" may not have been heard by the PAT25 crew because their microphone was keyed for 0.8 seconds, stepping on the Tower's transmission.

At 20:47:44, PAT25 stated they had the traffic in sight and requested visual separation, which was again approved by the controller. The Pilot Monitoring (PM) told the Pilot Flying (PF) that he believed ATC wanted them to move left, towards the East bank of the Potomac River.

At 20:47:58, the CRJ started increasing its pitch after a verbal reaction from the crew, with almost full deflection of the elevators. The collision occurred one second later, at 20:47:59.

While the Tower transmitted simultaneously on two VHF radio frequencies, PAT25 and the CRJ were communicating separately in one of each of those frequencies. This meant they could both hear the Tower, and vice-versa, but the two aircraft could not hear each other's transmissions.

The last radio altitude recorded by the CRJ, two seconds before impact, was 313 ft, and its descent rate was 448 ft/min. The pitch of the CRJ reached 9° nose-up after the crew's reaction, as well as a roll to 11° left wing down.

The last radio altitude recorded on the PAT25 FDR was 278 ft, steady for the previous 5 seconds. The pitch of the helicopter at the time of collision was about 0.5° nose-up with 1.6° of left roll.

The NTSB provided an explanation of the altitudes used by the aircraft crews and the radio altimeter altitudes recorded in the respective flight data recorders (FDRs). Flight crews normally rely on the barometric altitude displayed on altimeters installed on both sides of the cockpit. The displayed barometric altitude depends on the atmospheric pressure sensed by the static ports on the side of the aircraft and, when flying below 18 000 ft, on the reference atmospheric pressure (QNH) for the airport or region; the QNH is provided by ATC and must be manually set by the crew in each altimeter window. Barometric altimeters are very precise instruments but atmospheric pressure varies with time and weather conditions; an incorrect QNH value may result in an error of hundreds of feet. Neither the displayed barometric altitudes nor the QNH are recorded in the FDRs. The FDRs record pressure altitudes and, at low altitudes, radio altitudes. The pressure altitude is determined by the aircraft’s systems based on a standard atmosphere model and the NTSB has established that the pressure altitude recorded by the PAT25 helicopter was inconsistent (“bad data”). This pressure altitude is also transmitted by the aircraft transponder and displayed on the ATC radar screens, but as a “Flight Level” in hundreds of feet. Thus, if an aircraft has a pressure altitude between 101 ft and 200 ft, the controller will only see FL 002.

The radio altimeters bounce a signal off the surface of the earth and give a precise reading of the height of the aircraft’s belly above the ground, in this case the surface of the water of the Potomac River, which is essentially sea level. The radio altimeter value is also displayed in the cockpit, but although pilots may use it as a reference, their primary flight instruments are the barometric altimeters.

The NTSB also confirmed that PAT25 was not broadcasting ADSB data, which contains more information than the standard transponder, but it is not known at this time if this was due to a failure or because it was switched off.

Based on this preliminary but official information, the following can be concluded:

• The CRJ was on a normal flightpath and glidepath for a visual approach to runway 33, correctly lined-up and configured to land when the collision occurred at an altitude of about 300 ft.

• The visual approach to runway 33 (and the corresponding published RNAV (GPS) instrument approach) requires flying over helicopter Route 4 at an altitude below 400 ft. This theoretical vertical separation of less than 200 ft is NOT a safe separation even under ideal visual flight conditions (VMC) and should never have been permitted.

• When it collided with the CRJ, PAT25 was near the middle of the river channel when it should have been hugging the East bank of the river and it was nearly 100 ft above its maximum permitted altitude of 200 feet.

• A separation conflict alert was triggered in the DCA Tower about 19 seconds before the collision; this sounded an audible alarm and would also have been displayed on the controller’s radar screen.

• The CRJ crew received a Traffic Advisory (TA) from its TCAS about 18 seconds before the collision; a Resolution Advisory (RA), which would have commanded the crew to ascend, was not issued because these are inhibited below 1000 ft.