Engine Blade Failure on Ryanair Flight Left Passenger Partially Pulled Through Cabin Window, NTSB Finds
A broken engine fan blade on a Ryanair-operated Boeing 737-800 shattered a cabin window during a 10 July flight from Thessaloniki, Greece, to Memmingen, Germany, and the sudden loss of cabin pressure drew a passenger's head and right shoulder partway through the opening, according to a preliminary report from the US National Transportation Safety Board (BBC News).
The injured passenger was Serbian national Ljubisa Karović, who was left seriously injured and in shock. Greek authorities delegated the investigation entirely to the NTSB in the days after the incident. The aircraft was operated by Malta Air, a Ryanair subsidiary (BBC News; KDH News).
According to the NTSB report's timeline, reconstructed from flight crew accounts, the No. 2 (right) engine experienced a fan-blade-out — a failure in which a fan blade breaks free from the engine rotor — during the climb after takeoff. The crew first received a high-vibration engine alert, reduced engine power, and carried out checks. When vibrations appeared to stop, the crew continued climbing on autopilot. Engine vibrations then increased sharply and the crew heard a loud bang, prompting them to declare an emergency and begin descent. The flight crew returned to Thessaloniki International Airport (SKG), where they executed an uneventful landing (BBC News).
In the cabin, flight attendants reported hearing and feeling vibrations and observing a small amount of smoke before oxygen masks deployed. A flight attendant reported that a passenger had become partially lodged in a damaged cabin window, with the entire window missing. The breach in the cabin's pressure hull — the airtight inner shell that keeps cabin air pressurized at cruising altitude — created enough of a pressure difference to draw Karović partially through the aperture (BBC News).
The NTSB report noted that the engine had undergone ultrasonic inspections in May, with no findings of fault at that time. Ultrasonic inspection uses high-frequency sound waves to detect subsurface cracks and material flaws in engine fan blades before they grow large enough to cause failure. It is the standard non-destructive testing method for this purpose — meaning it checks for defects without taking the engine apart or damaging the component (BBC News).
Ryanair CEO Michael O'Leary suggested the incident may have been caused by foreign object damage to the engine — that is, debris from a runway or in the air being sucked into the engine. The NTSB preliminary report has not yet confirmed a root cause. The finding that the blade passed ultrasonic inspection roughly two months before the failure narrows the investigative focus toward either damage that occurred after that inspection or a defect that was too small to detect at the time of testing (BBC News).
What the Timeline Reveals
The flight crew's decision to continue climbing after the initial vibration alert subsided is a detail that will receive scrutiny as the investigation progresses. The NTSB timeline indicates the crew reduced power, ran checks, observed that vibrations had stopped, and then continued the climb on autopilot before the second, more severe vibration event and audible bang. This sequence raises questions about how transient engine vibration indications are evaluated in real time, and at what point flight crews are expected to treat such alerts as non-recoverable and initiate a diversion. The report is preliminary, and the NTSB has not issued findings of cause or contributing factors.
Cabin Window Integrity and Containment
A fan-blade-out event is a failure mode that turbofan engines are designed to handle safely. Certification standards require that an engine's containment case — a reinforced ring around the fan section — retain broken blade fragments within the engine housing so they cannot escape outward. The fact that engine debris penetrated the cabin and shattered a passenger window suggests either a containment failure or a failure path that bypassed the casing entirely. The NTSB's material and metallurgical examination of the fractured blade, when completed, will be critical to determining whether the failure originated from a pre-existing material defect, fatigue propagation (a crack that grows over repeated stress cycles), or an externally induced stress event such as foreign object damage.
The broader context here is the regulatory and maintenance framework governing engine fan-blade inspections across the global 737-800 fleet. The CFM56 engines that power this aircraft family have accumulated hundreds of millions of flight hours, and the inspection intervals and ultrasonic techniques applied to them are well-established. A blade passing inspection in May and failing in July is a relatively short interval, and investigators will need to determine whether the inspection was technically adequate, whether damage was introduced between the inspection and the failure, or whether the blade exhibited a failure mode that existing inspection protocols are not optimized to catch. If the root cause traces to a material or manufacturing defect, fleet-wide implications could follow. If foreign object damage is confirmed, the focus shifts to operational and environmental conditions at the airports the aircraft served in the intervening period.
The NTSB's final report, which will include probable cause and safety recommendations, is typically issued months after the preliminary findings.
