What happened
On June 19, 2015, an Embraer 1124A, registration PR-STJ, was performing a transport flight from Recife to Campinas with two pilots and three passengers on board. While cruising at FL 320 within the Salvador Terminal Area, the crew observed low hydraulic fluid pressure warnings for both the right and left engines.
Following the identification of the hydraulic system failure, the crew executed an immediate landing at Salvador Airport (SBSV). Although the aircraft landed safely on runway 10 and cleared the active runway, the crew attempted to taxi to the parking apron. During this taxi phase, near taxiway D, the aircraft lost nose wheel steering and braking capabilities. The aircraft veered to the right, exiting the taxiway and entering a grassy area, where the right main landing gear struck a concrete box. The incident resulted in light damage to the aircraft, but all five occupants were unharmed.
The investigation
CENIPA investigators examined the hydraulic system and discovered a puncture in a hydraulic pump hose on the right engine. The investigation revealed that the protective cover of the hose had degraded, and once removed, the perforation was visible. The failure was attributed to friction between the hose and a nipple within the engine nacelle housing.
Furthermore, the investigation found that the hydraulic hose lacked a proper identification plate containing the part number, manufacturer, and production date, which is a violation of Brazilian civil aviation regulations (RBAC 21 and RBAC 45). There were also no maintenance records found for this specific component. The aircraft had undergone a 200-hour inspection approximately six weeks prior to the event.
Findings
- Pilot judgment: The crew made an incorrect assessment by deciding to proceed with taxiing despite the known failure of the primary hydraulic system, which, according to the aircraft manual, results in the loss of nose wheel steering and primary braking.
- Aircraft maintenance: The friction between the hydraulic pump hose and the engine nacelle nipple was not identified during previous maintenance inspections.
- Management oversight: Maintenance supervision was inadequate, as the developing wear on the hydraulic hose was not detected during scheduled inspections.
Safety action
CENIPA issued several recommendations to the National Civil Aviation Agency (ANAC) regarding the operator and the maintenance facility:
- Ensure the operator reinforces pilot training regarding basic hydraulic system knowledge and emergency procedures.
- Ensure the maintenance facility strictly adheres to the manufacturer's maintenance manual, specifically regarding the inspection and positioning of hydraulic hoses within engine nacelles.
- Ensure all approved aeronautical products, such as hoses, meet regulatory requirements for proper identification and marking.