# Accident 20250519006459A: Eurocopter Deutschland Gmbh MBB-BK 117 C-1, Fort Washington, PA, May 19, 2025

- Type: FAA accident report (Accident/Incident Data System), as reported
- Date: May 19, 2025, 19:30 local time
- Place: Fort Washington, PA
- Damage: Substantial damage
- Phase of flight: Cruise/Level Flight
- Operating rules: Air taxi and commuter (Part 135)
- Operator: HDNA
- Location: 40.1164° N, 75.2428° W: From the FAA
- Nearby events: https://openairdocs.org/map.md?lat=40.1164&lon=-75.2428&mi=10
- Aircraft: N117NC, registered now (https://openairdocs.org/aircraft/N117NC) (OpenAirDocs)
- Registry model: Eurocopter Deutschland MBB-BK 117 C-1 (registry code 5626025, https://openairdocs.org/model/eurocopter-deutschland-mbb-bk-117-c-1) (OpenAirDocs)
- Registry engine: Turbomeca ARRIEL-1SER (registry code 60030, https://openairdocs.org/engine/turbomeca-arriel-1ser) (OpenAirDocs)
- Reported make and model: EUROCOPTER DEUTSCHLAND GMBH MBB-BK 117 C-1
- Reported engine: TURBOMECA ARRIEL 1SER
- People aboard: 3
- Fatal injuries: 0
- Other injuries: 1
- Pilot certificates: Commercial pilot
- Pilot flight hours: 3,000 total
- NTSB investigation: [NTSB ERA25LA204](https://openairdocs.org/ntsb/ERA25LA204) (OpenAirDocs)
- FAA source: FAA Aviation Safety Information Portal (https://asip.faa.gov/)
- Page: https://openairdocs.org/incident/20250519006459A

## Narrative

As the FAA filed it, in capitals; the FAA replaces private details with ^PRIVACY DATA OMITTED^.

DURING CRUISE FLIGHT, PILOT EXPERIENCED A SUDDEN YAW AND LOSS OF TAIL ROTOR CONTROL AND INITIATED AN EMERGENCY AUTOROTATION DESCENT AND LANDING IN A RESIDENTIAL AREA. DURING THE ONSITE INVESTIGATION THE TAIL ROTOR ASSEMBLY ALONG WITH THE UPPER PORTION OF THE TAIL BOOM WAS MISSING. A VISUAL INSPECTION OF THE MAIN ROTOR ASSEMBLY AREA SHOWED A LARGE AIR CONDITIONER PANEL WAS MISSING FROM THE UPPER CENTER OF THE FUSELAGE. SUBSTANTIAL DAMAGE WAS ALSO NOTED TO LEFT LANDING GEAR SKID AND IT'S ATTACH POINTS.

## The NTSB's investigation of this event (1)

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [NTSB ERA25LA204](https://openairdocs.org/ntsb/ERA25LA204), May 19, 2025: Eurocopter Deutschland MBB-BK 117 C-1 (N117NC), Fort Washington, PA, substantial damage. Probable cause: Maintenance personnel’s failure to identify and replace damaged rivet nuts at the air conditioning louver assembly, which resulted in the separation of the louver assembly from the helicopter, the…

From the FAA Accident/Incident Data System. Reports are matched to registry aircraft by N-number and event date, checked against the reported make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. For accidents, the NTSB's own investigation is the fuller record.

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