Flight AC-57 | Registration: C-FRSE
Date: 25 March 2025 | Location: Enroute over Italy, diverted to Frankfurt/Main (EDDF), Germany
⸻
Introduction
On 25 March 2025, an Air Canada Boeing 787-9 Dreamliner, registration C-FRSE, operating international long-haul service AC-57 from Dubai International Airport (OMDB), United Arab Emirates, to Toronto Pearson International Airport (CYYZ), Canada, diverted to Frankfurt/Main Airport (EDDF), Germany after the crew received a left hydraulic system low quantity warning while cruising over Italian airspace at FL320.
The flight crew declared a PAN-PAN with ATC and initiated a precautionary diversion, descending into Frankfurt where the aircraft landed safely approximately one hour later. All 304 occupants disembarked without incident. The Canadian Transportation Safety Board (TSB) later confirmed a leak in the engine-driven hydraulic pump return line.
⸻
Flight Details
• Aircraft Type: Boeing 787-9 Dreamliner
• Engines: 2 × General Electric GEnx-1B64
• Operator: Air Canada
• Tail Number: C-FRSE
• Flight Number: AC-57
• Departure Airport: Dubai International Airport (OMDB), UAE
• Planned Destination: Toronto Pearson International Airport (CYYZ), Canada
• Diversion Airport: Frankfurt/Main Airport (EDDF), Germany
• Date of Incident: 25 March 2025
• Occupants: 304 (Passengers and Crew Combined)
• Phase of Flight: Cruise (FL320)
• Time to Diversion Landing: Approx. 1 hour from detection
• Weather: No significant weather reported at diversion point
⸻
Sequence of Events
Enroute Detection and System Warning
While cruising over Italy at Flight Level 320 (approximately 32,000 feet), the flight crew of AC-57 received an alert indicating low quantity in the left hydraulic system. This system is critical for powering key aircraft functions including flight control surfaces, landing gear actuation, and braking systems.
Following standard Boeing and Air Canada procedures, the crew consulted the Quick Reference Handbook (QRH) and assessed potential system degradation. With the remaining system parameters stable and sufficient hydraulic redundancy on the Boeing 787, the crew declared a PAN-PAN and coordinated with ATC for a diversion to Frankfurt.
Diversion and Landing
Frankfurt/Main was selected as the most suitable diversion airport due to its long runways, available maintenance facilities, and operational readiness. The aircraft descended under full control and conducted a routine approach to runway 25C.
Landing occurred without further incident, and the aircraft taxied to the stand under its own power. Emergency services were on standby but not required.
⸻
Technical Investigation and Maintenance Findings
TSB Preliminary Report
The Transportation Safety Board of Canada (TSB) reviewed the incident and confirmed the following:
• A hydraulic fluid leak was traced to the left engine-driven pump return line.
• Associated components, including the engine pump, return line, and filter, were removed and replaced by maintenance teams at Frankfurt.
• No other damage or system faults were reported.
Aircraft Downtime and Recovery
The affected Boeing 787-9 remained grounded at Frankfurt for approximately 80 hours. It later positioned back to Toronto empty, following full rectification and safety checks.
⸻
Operational Impact
• Flight Disruption: Passengers were rebooked and transported to Toronto aboard a replacement aircraft.
• Replacement Aircraft: Airbus A330-300 registration C-GHKW departed Frankfurt and reached Toronto with a 6-hour delay.
• Passenger Care: Air Canada provided accommodations, meals, and rebooking assistance as per EU261 regulations.
⸻
Hydraulic System Overview – Boeing 787-9
The Boeing 787 is equipped with three independent hydraulic systems—left, right, and center—powered by engine-driven pumps, electric motor-driven pumps, and backup actuators. These systems power:
• Primary flight controls (elevators, rudder, ailerons)
• Landing gear and brakes
• Nose wheel steering
• Thrust reversers (on certain configurations)
The design provides redundancy, allowing the aircraft to continue safe flight and landing in the event of a single-system failure or leakage.
Hydraulic Fluid Monitoring
Each system includes reservoir sensors for pressure and quantity. A low quantity indication can signify a leak or failure and prompts immediate crew evaluation and procedural action. In AC-57’s case, the system retained sufficient pressure, but the precautionary diversion was a textbook decision in line with Boeing and ICAO flight safety protocols.
⸻
Safety and Industry Considerations
Why This Matters
While not uncommon, in-flight hydraulic anomalies on long-haul aircraft can have cascading effects on operational availability and passenger confidence. The ability of the flight crew to detect, assess, and safely divert highlights:
• Crew competency and training
• Robust aircraft system design
• Effective contingency planning
Implications for Maintenance and OEMs
The leak in the return line—rather than a pressure side failure—limited fluid loss and preserved flight control functionality. Investigators will evaluate the component fatigue, installation procedures, and scheduled inspection intervals to determine if broader fleet checks are warranted.
⸻
Conclusion
The diversion of Air Canada Flight AC-57 exemplifies aviation’s layered approach to safety, from flight crew decision-making to technical system resilience. The event concluded without injury or damage and reinforced the importance of proactive response to flight deck alerts.
A final statement from Air Canada and the TSB is expected following routine post-incident analysis.
⸻
Disclaimer
This article is based on publicly available information and reports as of 3 April 2025. While every effort has been made to ensure accuracy, we cannot guarantee the completeness of the information provided.
If you are the rightful owner of any referenced content and wish it to be removed, please email takedown@cockpitking.com.
