What happened
On January 26, 2016, an EMB 110, registration PT-ODY, operated by Apuí Táxi Aéreo Ltda., was performing a charter flight from São Gabriel da Cachoeira, AM, to Marechal Thaumaturgo, AC. The flight carried two pilots and seven passengers.
Upon landing at the Marechal Thaumaturgo aerodrome, the aircraft traveled approximately 40 meters along the runway before the crew noticed excessive vibration in the main landing gear wheel. In an attempt to relieve the pressure on the gear, the commander applied back pressure on the control column. After approximately five seconds, the vibration ceased, but the crew realized the main landing gear wheel had detached, causing the gear strut to drag along the runway. The aircraft came to a halt shortly thereafter. All nine occupants escaped the aircraft without injury, though the aircraft sustained light damage to the landing gear assembly.
The investigation
CENIPA's investigation focused on the mechanical failure of the landing gear and the environmental conditions of the aerodrome. Investigators examined the landing gear strut, which was sent to the Department of Aerospace Science and Technology (DCTA); tests showed that the damage was caused by friction with the ground during the event rather than a pre-existing structural fracture.
The investigation also reviewed the runway conditions at the time of the incident. The pavement at the Marechal Thaermaturgo aerodrome was found to have numerous holes and cracks. Furthermore, investigators compared the aircraft's weight to the runway's Pavement Classification Number (PCN). At the time of landing, the aircraft weighed 4,535 kg, which exceeded the runway's rated PCN of 3,970 kg.
Findings
- Inadequate flight planning: The crew did not adequately account for the physical limitations of the aerodrome, specifically the mismatch between the aircraft's weight and the runway's load-bearing capacity.
- Inadequate managerial supervision: The operator failed to ensure that flight planning and execution processes accounted for the specific pavement limitations of the destination aerodrome.
- Airport infrastructure: The poor state of the runway, characterized by cracks and holes, likely contributed to the tire failure and subsequent loss of the wheel assembly.
- Uncertainty regarding control inputs: It remains undetermined if a heavy or three-point landing contributed to the sudden stress that caused the wheel hub to detach.