Overview
• Operator: Republic Airways on behalf of American Airlines
• Aircraft Model: Embraer ERJ-175
• Registration: N424YX
• Flight Number: AA-4565
• Route: New York La Guardia (NY) to Indianapolis (IN), USA
• Date: 20 January 2025
• Occupants: Passengers and crew unspecified
Incident Summary
Republic Airways flight AA-4565 encountered an unusual odour while cruising at FL320, approximately 110 nautical miles east of Pittsburgh, Pennsylvania. The crew initiated a rapid descent to 10,000 feet, reporting the odour and requesting medical assistance for a flight attendant upon arrival. The aircraft landed safely at Pittsburgh International Airport and stopped clear of the runway to await emergency services. Emergency responders did not observe smoke or visible external issues with the aircraft.
Sequence of Events
1. Cruise Phase:
• The aircraft was enroute at FL320 when the crew detected an unusual odour on board.
2. Rapid Descent:
• In response to the odour, the crew initiated a rapid descent to 10,000 feet.
• The odour reportedly dissipated below 10,000 feet.
3. Landing and Inspection:
• The flight landed safely on Pittsburgh’s runway 28L at approximately 10:55 local time.
• Emergency services inspected the aircraft but reported no visible smoke or external issues.
4. Medical Assistance:
• An ambulance was requested at the runway to assess the condition of a flight attendant who may have been affected by the odour.
5. Replacement Aircraft:
• Passengers were transferred to a replacement Embraer ERJ-175, registration N425YX, which continued to Indianapolis, resulting in a delay of approximately 2 hours and 15 minutes.
FAA Statement
The Federal Aviation Administration (FAA) confirmed the safe landing and indicated that the diversion occurred due to a reported mechanical issue. The FAA has opened an investigation into the incident.
Aircraft Status
The affected aircraft, N424YX, remained on the ground in Pittsburgh for about 5.5 hours before returning to service.
Analysis and Recommendations
The source of the odour remains under investigation. Potential causes include air conditioning system malfunctions, fluid leaks, or electrical issues. In-flight odours can pose health risks, particularly in pressurised environments, and the crew’s decision to descend rapidly and prioritise medical assistance aligns with best practices for passenger and crew safety.
Maintenance inspections should focus on the aircraft’s environmental control system and possible contaminants within the cabin air supply. A review of air quality monitoring systems and protective measures for crew and passengers during odour-related events is recommended.
Disclaimer
This report is based on available information as of 22 January 2025. While every effort has been made to ensure accuracy, the completeness of the details cannot be guaranteed. If you are the rightful owner of any referenced materials and wish them removed, please email takedown@cockpitking.com.
