23/08/2025
NTSB issues the preliminary report for its ongoing investigation of the May 1 loss of separation event between a UH-60 Blackhawk helicopter landing at the Pentagon Heliport and an Embraer 170 (Republic Airways flight 5825) on approach to Reagan Washington National Airport (DCA) near Washington,
DC.
Aviation Investigation Preliminary Report
Location: Washington, DC
Incident Number: OPS25LA034
Date & Time: May 1, 2025, 14:33 Local
Registration: N879RW (A2); UNREG (A3)
Aircraft: Embraer ERJ 170-100 LR (A2); Sikorsky UH60 (A3)
Injuries: N/A (A2); N/A (A3)
Flight Conducted Under: Part 121: Air carrier - Scheduled (A2); Armed Forces (A3)
On May 1, 2025, about 1433 eastern daylight time (EDT), Priority Air Transport flight 23 (PAT23), (tail number forthcoming), a UH-60 Blackhawk helicopter landing at the Pentagon Heliport (JPN), and Republic Airways flight 5825 (RPA5825), an Embraer 170, N879RW, on approach for landing Ronald Reagan Washington National Airport (DCA), Arlington, Virginia, were involved in a loss of separation approximately 1.7 miles north-northwest of DCA. PAT23 was operating as a title 14 Code of Federal Regulations (CFR) Part 91 military flight, and RPA5825 was operating as a title 14 CFR Part 121 scheduled passenger flight. According to the FAA, the closest proximity between PAT23 and RPA5825 was 0.4 miles laterally and 200 feet vertically.
The DCA Airport Traffic Control Tower (ATCT) local control (LC) controller was providing services to both involved aircraft when the loss of separation occurred. At the time of the incident there were five positions open in the tower: LC, assistant LC (ALC), ground control (GC), clearance delivery (CD) / flight data (FD), and operations supervisor (OS). Four CPCs (Certified Professional Controllers), one trainee and one OS were on position. The LC position, which was the position involved with training in progress, was combined with the helicopter control (HC) position. The operations manager (OM) had authorized the HC and LC positions to be combined for training. An OS was providing direct supervision. There was one CPC, one OS, and one OS in training (IT) available, with three CPCs and one trainee performing other duties.
Surveillance data provided by the Federal Aviation Administration (FAA) indicated that PAT23 was inbound to JPN from the southwest via helicopter route 5, Pentagon transition. There were three fixed wing aircraft inbound to runway 19 at DCA. These were (in order): PSA Airlines flight 5073 (JIA5073); Delta Air Lines flight 1671 (DAL1671); and RPA5825.
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At about 1421 EDT, PAT23 contacted the DCA ATCT LC controller over Springfield and requested to fly helicopter route 5 to the Pentagon. The controller provided the current DCA altimeter setting, radar identified them and advised them of helicopter traffic transiting westbound at 1,200 feet through helicopter zones 5 and 6. The crew acknowledged and advised they were looking for traffic.
At about 1423 EDT, the DCA ATCT LC controller instructed PAT23 to hold three miles west of DCA. The crew acknowledged and read back the holding instructions.
At about 1424 EDT, the DCA ATCT LC controller instructed PAT23 to proceed to the Glebe Road intersection and hold. The crew acknowledged and read back the instructions.
At about 1425 EDT, JIA5073 checked in with the DCA ATCT LC controller on the River Visual Approach to runway 19. The LC controller issued the winds and cleared JIA5073 to land runway 19.
Also, about this time, the DCA ATCT ALC controller coordinated with Potomac Terminal Radar Approach Control (PCT TRACON) to ask for extended spacing between JIA5073 and RPA5825 that was next in sequence for runway 19. The PCT TRACON radar controller confirmed they would give them some space.
[Between 1425 and 1428 EDT, PCT TRACON had sequenced DAL1671 into the extended spacing that they had advised DCA ATCT they would provide so that DCA ATCT could get PAT23 into JPN.]
At about 1428 EDT, the DCA ATCT LC controller instructed PAT23 to proceed to the Pentagon via helicopter route 5. The crew acknowledged and read back the instructions.
At about 1429 EDT, DAL1671 checked in with the DCA ATCT LC controller on the Area Navigation (RNAV) Zulu approach to runway 19. The LC controller issued the winds, advised of traffic holding in position and cleared them to land runway 19.
Also, about this time, PAT23 reported Glebe Road. The DCA ATCT LC controller acknowledged.
At about 1431 EDT, the DCA ATCT LC controller instructed PAT23 to report landing assured. The crew acknowledged and said “will do.”
Immediately after the response from PAT23, the DCA ATCT LC controller instructed DAL1671 to go around, to climb and maintain 3,000 feet, and to turn right heading 280°. The crew acknowledged and read back the instructions. At the same time, the DCA ATCT ALC controller immediately began coordinating the go around with PCT TRACON.
Exact times have not yet been determined from the Department of Defense audio, but around this time, PAT23 had checked in with the JPN Heliport Tower (HT) LC controller and was attempting to land on the helipad without a landing clearance. When the JPN HT LC controller queried the crew to ask who had cleared them to land, the crew advised they were executing a go around and that DCA ATCT had cleared them to the helipad.
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At about 1432 EDT, RPA5825 checked in with the DCA ATCT LC controller inbound on the River Visual Approach to runway 19. The LC controller issued the winds, advised of traffic that would be holding in position and cleared them to land runway 19.
At about 1433 EDT, the DCA ATCT LC controller asked PAT23 if they were landing assured, and the crew advised they were landing assured. Simultaneously, according to information provided in post-incident interviews, the DCA ATCT LC saw PAT23 climb back up above the Pentagon building and immediately issued a go around to RPA5825 and instructed them to climb and maintain 3,000 feet and turn right heading 250°. The crew of RPA5825 acknowledged the go around, and read back the instructions, however separation had already been lost.
Figure 1 is an overhead view of the flight tracks of both RPA5825 and PAT23 and indicates their approximate location at the point of closest proximity.
Upon initial notification, the NTSB requested additional data from both the FAA and the Department of Defense (DOD). After receiving and conducting a review of this preliminary data, the NTSB formed an ATC investigative group and parties to the investigation include the FAA, the National Air Traffic Controllers Association (NATCA), and the United States Army.
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Automatic Dependent Surveillance – Broadcast (ADS-B) data, audio recordings, and other pertinent data and documentation were obtained from the FAA. These data are currently being analyzed by the NTSB.
During the week of June 15th, 2025, the ATC investigative group conducted an on-site investigation and interviewed personnel at both DCA ATCT and JPN HT, the ATC facilities that had provided services to RPA5825 and PAT23 at the time of the incident. The group conducted interviews with controllers and also met with technical operations personnel responsible for communications installation and maintenance at both facilities. All information gathered confirmed that there had been no known or documented loss of communication at any time between JPN HT and PAT23, and that there had been no replacement or movement of any communication equipment since the event, and that information previously released regarding the potential loss of communications had been erroneous.
Aircraft and Owner/Operator Information (A2)
Aircraft Make: Embraer
Registration: N879RW
Model/Series: ERJ 170-100 LR
Aircraft Category: Airplane
Amateur Built: –
Operator: DELTA AIR LINES INC
Operating Certificate(s) Held: Flag carrier (121)
Operator Designator Code: –
Aircraft and Owner/Operator Information (A3)
Aircraft Make: Sikorsky
Registration: UNREG
Model/Series: UH60
Aircraft Category: Helicopter
Amateur Built: –
Operator: Army Department of Defense
Operating Certificate(s) Held: None
Operator Designator Code: –
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Meteorological Information and Flight Plan
Conditions at Accident Site: VMC
Condition of Light: Day
Observation Facility, Elevation: KDCA, 13 ft msl
Observation Time: 13:52 Local
Distance from Accident Site: 2 Nautical Miles
Temperature/Dew Point: 26°C / 18°C
Lowest Cloud Condition: Few / 5000 ft AGL
Wind Speed/Gusts, Direction: 4 knots / None
Visibility: 10 miles
Altimeter Setting: 30 inches Hg
Type of Flight Plan Filed: IFR (A2); MVFR (A3)
Departure Point: Fairfax County, VA (DAA) (A3)
Destination: Washington, DC (A2); Washington, DC (JPN) (A3)
Wreckage and Impact Information (A2)
Crew Injuries: N/A
Passenger Injuries: –
Ground Injuries: N/A
Aircraft Damage: None
Aircraft Fire: None
Aircraft Explosion: None
Total Injuries: N/A
Latitude, Longitude: 38.877083, -77.051003 (est)
Wreckage and Impact Information (A3)
Crew Injuries: N/A
Passenger Injuries: –
Ground Injuries: N/A
Aircraft Damage: None
Aircraft Fire: None
Aircraft Explosion: None
Total Injuries: N/A
Latitude, Longitude: 38.877083, -77.051003 (est)
Administrative Information
Investigator In Charge (IIC): Soper, Brian
Additional Participating Persons:
Claude Vieira; FAA; Jamaica, NY
Kristen McTee; NATCA; Denver, CO
Joseph Frasier; United States Army - DOD; Stafford, VA
Investigation Class: Class 3
Note: The NTSB did not travel to the scene of this incident.