Event
On 10 July 2005 at 14:56 UTC, a Cessna 172M aircraft, registration I-UDDY, operated by Aero Club Milano, experienced a serious incident during landing at Biella Cerrione Airport (LILE). The aircraft, on an instructional navigation flight from Bresso (LIMB) with a student pilot and an instructor on board, veered to the right immediately after touchdown. The instructor took control but found the rudder pedals ineffective. He applied brakes, and the aircraft came to a stop on the grass adjacent to the runway, near a parallel taxiway. The aircraft was later taxied back to the parking area. The two occupants were unharmed, but the runway excursion caused damage to two runway lights near taxiway R2.
Aircraft Information
The Cessna 172M (serial number built by Reims Aviation in 1976) was a single-engine, high-wing, four-seat aircraft with a tricycle landing gear. It was powered by a Lycoming O-320-E2D engine. The aircraft had a standard airworthiness certificate and had undergone its most recent periodic inspection on 5 July 2005, which included checks of the flight control cables and their tension. No anomalies were found at that time. The aircraft had flown 13 hours and 50 minutes since that inspection.
Investigation Findings
The investigation, conducted by the Italian National Agency for Flight Safety (ANSV), determined that the left rudder control cable (Part Number 05100105-339) had ruptured. The break occurred approximately 1.5 mm inside the swaged fitting at the forward attachment to the rudder pedal, a location difficult to inspect visually. Visual examination of the cable revealed no corrosion at the fracture point, and the rupture was attributed to a fatigue phenomenon. The Cessna 172 maintenance manual does not require specific non-destructive inspections of control cables at the pedal attachment points, only tension checks and positioning verification.
In response to similar issues, the French DGAC had issued Bulletin of Recommendation BR 2005/14(A) on 16 March 2005, recommending detailed visual inspections of cable ends for cracks or corrosion. This bulletin was based on FAA Special Airworthiness Information Bulletin CE-01-30 and Piper Service Bulletin 1048. The UK Civil Aviation Authority also issued Airworthiness Notice No. 12, Appendix 65 on 18 March 2003.
Safety Actions
As a provisional preventive action, the technical office of Aero Club Milano modified its maintenance procedures for Cessna 172 aircraft, adding a reference to FAA Advisory Circular AC 43.13 and requiring the application of Piper Service Bulletin 1048 by similarity, with particular attention to wire integrity at the swaged ends.