What happened
On October 29, 2016, a Piper PA34-200T, registration CX-JLS, was conducting a local flight at Angel S. Adami International Airport (SUAA) in Montevideo, Uruguay. The flight involved two commercial pilots performing maneuvers for flight proficiency and a passenger.
During the initial climb following takeoff, the crew observed that the nose gear had failed to retract. After attempting to cycle the gear and verifying the status via cockpit lights, the crew decided to return to the airport. During the landing on runway 01, the aircraft's configuration warning horn failed to activate. While taxiing after touchdown, the nose gear retracted unexpectedly. The aircraft's nose slid along the pavement, causing the propellers to strike the ground. All three occupants evacuated the aircraft without injury, and no fire or fuel spills occurred.
The investigation
The CIAIA investigation focused on the mechanical failure of the landing gear and the discrepancies found in the aircraft's maintenance records. Investigators examined the aircraft's logs, including engine and propeller records, and compared them against the actual components installed on the aircraft.
Technical inspections revealed significant inconsistencies between the maintenance documentation and the physical state of the aircraft. Specifically, investigators found that several maintenance tasks, such as the replacement of certain bolts and filters, were not properly documented in the aircraft's logs or official forms. Furthermore, the investigation noted that the maintenance of the three-bladed propellers (installed via STC) was not being cross-referenced with the standard two-bladed propeller maintenance manual, and several Airworthiness Directives (ADs) were not accurately tracked in the aircraft's records.
Findings
- The investigation established that the failure to follow manufacturer-established maintenance procedures was the primary factor in the accident.
- Physical evidence of wear on various components demonstrated that maintenance protocols were not being strictly adhered to.
- There was a lack of synchronization between the aircraft's technical logs and the actual components installed on the airframe.
- The breakage of the downlock link caused the drag link geometry to shift, leading to the unintended retraction of the nose gear.