Nose gear axle failure causes loss of wheel on Boeing 737

Casualties unknown • Aeroporto di Treviso S.Angelo, IT

A Boeing 737-800 experienced a nose gear axle fracture during landing at Treviso, resulting in the loss of the left nose wheel.

What happened

On June 25, 2007, a Boeing 737-800, registration EI-CSN, operating a commercial passenger flight from Girona, Spain, to Treviso S.Angelo Airport, experienced a landing gear failure. The aircraft, carrying 174 passengers and 6 crew members, was performing an ILS approach to runway 07 under favorable weather conditions.

Shortly after touchdown, as the aircraft decelerated to approximately 100 knots, the crew reported a loud bang accompanied by a slight left roll, which the pilot quickly corrected. During the subsequent taxi to the parking stand, the crew discovered that the left nose gear axle had fractured, causing the left nose wheel to detach from the aircraft. The detached wheel was located two days later in a grassy area near the airport taxiways.

The investigation

The ANSV examined the fractured inner cylinder assembly of the nose gear, specifically the axle. Metallurgical and fractographic analyses were conducted in coordination with the Italian Air Force Experimental Flight Center. The investigation also included a review of the flight data recorder (FDR) and cockpit voice recorder (CVR) to evaluate the landing conditions and aircraft handling.

Investigators compared this event to a similar incident involving another Boeing 737 (EI-COI) that occurred in Catania in June 2006. The investigation also reviewed maintenance records, noting that the aircraft had undergone a 'C1' inspection only 19 days prior to the event.

Probable cause

The failure of the nose gear axle was caused by stress corrosion cracking, initiated by generalized corrosion and pitting on the component's surface, which was undetectable during standard scheduled maintenance due to the location of the defect under a non-removable spacer.

Frequently asked questions

What happened in the 2007-06-25 Boeing B737-800, accident near Aeroporto di Treviso S.Angelo, IT?

A Boeing 737-800 experienced a nose gear axle fracture during landing at Treviso, resulting in the loss of the left nose wheel.

What aircraft was involved and where did it happen?

The accident on 2007-06-25 involved a Boeing B737-800,, registration EI-CSN, at Aeroporto di Treviso S.Angelo, IT.

What was the probable cause of the accident?

The failure of the nose gear axle was caused by stress corrosion cracking, initiated by generalized corrosion and pitting on the component's surface, which was undetectable during standard scheduled maintenance due to the location of the defect under a non-removable spacer.

Loading the flight search…