What happened
On June 7, 2017, an Embraer 190-200 operating a scheduled flight from Warsaw to Moscow encountered a hydraulic system malfunction near Minsk. While en route, the crew observed a "HYD2LO QTY" message on the cockpit displays. Upon investigation, the crew determined that the hydraulic fluid level in system number 2 had dropped to 16% and was continuing to decrease. As the level reached 2%, an EICAS warning for "HYD 2 LO PRESS" was triggered.
The crew performed the required procedures from the Quick Reference Handbook (QRH) for low hydraulic pressure, but these actions did not stop the fluid loss. After notifying the Maintenance Control Center (MCC), the flight continued to Moscow Sheremetyevo (SVO). To ensure a safe arrival, the crew utilized the alternate gear extension lever to deploy the landing gear. The aircraft landed at SVO without further incident.
The investigation
Following the landing, a technical inspection revealed traces of hydraulic fluid leaking from the right engine cowling. Maintenance personnel replaced the Engine Driven Pump (EDP) on engine number 2; however, subsequent testing showed that the leak persisted from the pylon area.
Upon removing the access panels to the hydraulic lines within the pylon, investigators identified a leak source on a specific hydraulic line (TUBE ASSY PN190-05170-401). Analysis of the flight data recorder (DFDR) was also conducted as part of the technical review. The investigation determined that the leak was caused by the metal portion of a mounting clamp rubbing against the hydraulic line.
Findings
- The loss of hydraulic fluid in system number 2 was caused by the abrasion of a hydraulic tube (TUBE ASSY P/N 190-05170-401) due to friction from a metal mounting clamp.
- Meteorological conditions during the flight had no impact on the occurrence.