What happened
On August 31, 2013, an Embraer EMB-810C, registration PT-WBZ, operated by Brasil Vida Táxi Aéreo Ltda, was performing a charter flight when it experienced a serious incident during landing at Cachoeiro de Itapemirim (SNLN), Brazil. Following the touchdown on the runway, the landing gear unexpectedly retracted. This retraction caused the propellers of both engines to strike the ground, resulting in the aircraft veering left and exiting the runway. Only the vertical stabilizer remained on the paved surface. The aircraft sustained substantial damage during the excursion.
The investigation
CENIPA investigators examined the aircraft and the flight sequence to determine why the gear retracted despite the pilot's report of a successful deployment. The investigation noted that there were no tire marks on the runway at the point of contact, only marks left by the aircraft's belly. The propeller blades showed twisting consistent with the level of the fuselage upon impact, and the landing gear struts showed no signs of damage.
Post-accident technical tests were conducted on the aircraft's hydraulic system. The investigation established that the hydraulic fluid was clean and at the correct level, the hydraulic pump was functioning normally, and there were no internal or external leaks or pressure losses. Furthermore, the mechanical landing gear locks were found to be intact and functional, and the landing gear position indicator lights and the cockpit warning horn were all fully operational. While the pilot maintained that the gear was commanded down, confirmed via cockpit lights, and locked, the physical evidence indicated the gear retracted after the aircraft touched the runway.
Findings
- The pilot and passenger were both unharmed.
- The aircraft was within weight and balance limits, and all required certifications (CMA, CHT, and CA) were valid.
- The hydraulic system, including the pump, fluid levels, and pressure, was fully functional.
- The mechanical locks and landing gear indicators were operational.
- The cause of the landing gear retraction remains undetermined, as all mechanical and hydraulic systems were found to be in proper working order despite the gear retracting after touchdown.