Overview
• Operator: Republic Airways on behalf of American Airlines
• Aircraft Model: Embraer ERJ-175
• Registration: N112HQ
• Flight Number: AA-4689
• Route: Washington National, DC (USA) → Miami, FL (USA)
• Date: 8 February 2025
• Occupants: 80 (Passengers and Crew)
• Nature of Incident: Slat system malfunction
Incident Summary
Republic Airways flight AA-4689, operated by an Embraer ERJ-175 (N112HQ), departed Washington National Airport (DCA) bound for Miami. Shortly after takeoff from runway 19, the crew identified a problem with the slats during climb and stopped the ascent at FL240.
The crew subsequently decided to divert to Washington Dulles International Airport (IAD) for a precautionary landing. The aircraft landed safely on runway 19C approximately 65 minutes after departure.
A replacement aircraft, another Embraer ERJ-175 (N125HQ), was dispatched to continue the flight, resulting in a 5-hour delay for passengers.
Sequence of Events
Climb and Slat Malfunction
• Shortly after departure, the crew detected an issue with the slat system, preventing normal aerodynamic function.
• The aircraft levelled off at FL240 while troubleshooting the issue.
Decision to Divert
• Due to safety concerns regarding possible landing configuration limitations, the crew opted to return to Washington but diverted to Dulles (IAD) instead of National (DCA) for a longer runway and enhanced emergency services.
• The aircraft performed a safe landing on runway 19C at Washington Dulles.
Passenger and Flight Arrangements
• Passengers were transferred to a replacement aircraft (N125HQ) which departed for Miami after a delay of approximately 5 hours.
Aircraft Status
• The occurrence aircraft remained grounded for about 63 hours before positioning to Indianapolis (IND) for further maintenance.
Technical Analysis & Possible Causes
The slat system on the Embraer ERJ-175 plays a crucial role in low-speed flight characteristics, particularly takeoff and landing performance. A malfunction could result in:
1. Asymmetrical deployment, affecting aircraft control.
2. Failure to retract properly, increasing drag and reducing climb performance.
3. Failure to extend, impacting approach and landing speeds.
Potential causes of slat system malfunctions include:
• Hydraulic system failures affecting slat actuation.
• Electrical or sensor issues preventing correct deployment signals.
• Mechanical jamming due to debris or component wear.
Safety Considerations & Recommendations
• Thorough inspection of the slat actuators and control systems should be conducted before returning the aircraft to service.
• A review of recent maintenance records should determine if any prior slat-related discrepancies were noted.
• Flight crew actions were appropriate, ensuring passenger safety by choosing a longer runway and better-equipped airport for landing.
Disclaimer
This report is based on available information as of 11 February 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.
