Event Description
On 10 July 2005 at 14:56 UTC, a Cessna 172M aircraft, registration I-UDDY, operated by Aero Club Milano, was conducting a training flight from Bresso airport (LIMB) to Biella Cerrione airport (LILE). The flight was a navigation training exercise with a student pilot and an instructor on board. During the landing phase, immediately after touchdown while decelerating, the aircraft yawed to the right. The instructor ordered the student to release the controls and attempted to counter the yaw but found the rudder pedals completely ineffective. The instructor then used the brakes to slow the aircraft, which came to a stop on the grass beside the runway, near a parallel taxiway. The aircraft was subsequently taxied back to the parking area.
Occupant and Damage Information
Both occupants, the instructor and the student pilot, were uninjured. The aircraft sustained a broken left rudder control cable (part number 05100105-339). Additionally, an inspection conducted the day after the event by airport management (SACE S.p.A.) and firefighting personnel revealed that the aircraft had struck and damaged two runway lights near taxiway R2. Photographic evidence showed skid marks from braking and the displaced lights.
Aircraft Information
The Cessna 172M is a four-seat, single-engine, high-wing monoplane with tricycle landing gear, manufactured by Reims Aviation in 1976. It was powered by a Lycoming O-320-E2D engine. The aircraft had a standard airworthiness certificate valid for normal, semi-acrobatic, training, and touring operations. The last periodic inspection (500-hour airframe and 200-hour engine) was completed on 5 July 2005, with 13 hours and 50 minutes flown since. Control cable tension and travel had been checked during that inspection with no anomalies noted.
Investigation Findings
Visual examination of the broken rudder cable revealed that the fracture occurred approximately 1.5 mm inside the swaged terminal at the forward attachment to the rudder pedal, a location difficult to inspect visually. No corrosion was found at the fracture surface, and the break was likely due to fatigue. The maintenance manual for the Cessna 172 series does not require specific non-destructive inspections of control cables at these critical attachment points, only tension and positioning checks.
Relevant Safety Information
The French DGAC had issued Recommendation Bulletin BR 2005/14(A) on 16 March 2005 concerning inspection of stainless steel control cables for certain Piper, Cessna, and Reims Aviation aircraft, including the Cessna 172. This bulletin recommended detailed visual inspection of cable ends for cracks or corrosion. The recommendation was based on FAA Special Airworthiness Information Bulletin CE-01-30, which referenced Piper Service Bulletin 1048. The UK CAA had also issued Airworthiness Notice No. 12, Appendix 65 on 18 March 2003. In response, the technical office of Aero Club Milano modified its maintenance procedures for Cessna 172 aircraft to include additional checks per FAA AC 43.13 and Piper SB 1048, with emphasis on inspecting cable strands at swaged terminals.