What happened
On March 28, 2014, a Fokker F28MK0100, registration PR-OAF, operated by Oceanair Airlines, was performing a scheduled cargo and passenger flight from Petrolina to Brasília. Approximately thirty minutes after takeoff, the crew identified a low fluid level in hydraulic system 1. Following established operational procedures, the crew continued the flight to Brasília with the degraded system.
During the landing phase at Presidente Juscelino Kubitschek International Airport, the crew utilized the aircraft's alternative system to deploy the landing gear. While the main landing gears successfully deployed and locked, the nose landing gear remained in the retracted position. Although the gear doors unlocked, the nose gear itself failed to extend.
The aircraft touched down on runway 11R. For the first 750 meters of the landing roll, the aircraft was supported solely by the main landing gears. During the final 150 meters, the lower part of the front fuselage made contact with the runway surface. The aircraft came to a full stop after traveling a total of 900 meters. The impact caused substantial structural damage to the nose section, including deformation of the fuselage coating and internal structural elements. While the evacuation was orderly, the copilot sustained serious injuries involving fractures to the thoracic spine; all other crewmembers and the 44 passengers were unharmed.
The investigation
CENIPA's investigation focused on the mechanical failure of the nose landing gear deployment and the preceding hydraulic system degradation. Investigators examined the hydraulic system 1, which had experienced a leak due to gasket extrusion in the Engine-Driven Pump (EDP 1).
Technical analysis of the nose landing gear assembly revealed that the right-side door hinge was experiencing significant movement restrictions. The investigation determined that the weight of the nose landing gear assembly was insufficient to overcome the friction caused by these restricted hinges. Furthermore, investigators looked into the maintenance history of the hinges, noting a lack of recent lubrication and potential issues related to previous structural rework on the hinge pins and holes.
Findings
- A fluid leak in the Engine-Driven Pump (EDP 1) caused the low level in hydraulic system 1.
- The restriction of movement in the right nose landing gear door prevented the nose gear from extending via the alternative gravity-extension system.
- The right door hinges showed no signs of recent lubrication, suggesting a possible deviation from manufacturer-established maintenance or inspection requirements.
- There was a possibility that previous maintenance work—specifically the widening of hinge holes to accommodate larger pins—had created a surface susceptible to corrosion or mechanical binding.
- The manufacturer's maintenance program may not have provided adequate preventive parameters for these specifically modified landing gear door hinges.