What happened
On October 7, 2012, an Embraer EMB-810C, registration PT-ELG, was performing a ferry flight from Campinas to Catanduva, Brazil, when the pilot encountered a landing gear malfunction. During the final approach to the Catanduva Aerodrome, the pilot attempted to extend the landing gear but found that the nose gear strut failed to deploy. Despite following all emergency procedures, including cycling the gear and attempting to use gravity to assist deployment, the nose gear remained retracted.
The pilot decided to perform an emergency landing on a grassy area adjacent to the runway. To prepare for the impact, the pilot retracted the flaps, adjusted the fuel mixture to reduce landing weight, and ensured the cabin doors were unlocked. The aircraft contacted the ground with the nose gear retracted, sliding approximately 120 meters. While the pilot and three passengers escaped uninjured, the aircraft sustained significant damage to the engine, propeller tips, and the lower fuselage.
The investigation
CENIPA investigators examined the aircraft's maintenance history and the mechanical state of the nose gear assembly. Although the aircraft's airworthiness certificate was valid and recent inspections were up to date, the investigation revealed that the maintenance logs for the airframe, engines, and propellers were outdated.
Upon inspecting the nose gear compartment, investigators found evidence of chafing on a tube within the actuator mechanism. The investigation determined that a bolt used in the lateral vibration damper had been installed incorrectly. Specifically, the bolt was mounted with the head facing the wrong direction, and the washer configuration did not comply with the manufacturer's specifications. This improper installation caused the bolt's nut to rub against the actuator tube, eventually preventing the gear from extending.
Further investigation revealed that the maintenance work—replacing the bolt—had been performed by an unlicensed, independent mechanic rather than a certified repair station. The pilot had initiated the replacement after being advised by a peer about potential issues with similar bolts on other aircraft. Additionally, the compartment had been recently painted in a manner that did not follow manual specifications, which could have masked signs of wear or corrosion.
Findings
- The nose gear failed to extend because the lateral vibration damper bolt was installed in an inverted position.
- Improper maintenance was performed by an unlicensed mechanic not authorized by the National Civil Aviation Agency (ANAC).
- The maintenance work was not recorded in the aircraft's official logs.
- The incorrect installation of the bolt caused physical interference (chafing) with the nose gear actuator tube.
- The use of non-standard painting techniques in the gear compartment may have obscured mechanical issues.