Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine; Flight Crew Instrument
Flight Crew Last 90 Days 72; Flight Crew Total 5500; Flight Crew Type 750
Troubleshooting
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Landed As Precaution; Flight Crew Overcame Equipment Problem; Flight Crew Diverted; General Flight Cancelled / Delayed; General Maintenance Action
Aircraft
While in cruise flight at Flight Level 380 the amber Hydraulic Overheat annunciator illuminated; the check list was performed for the corresponding annunciator which indicated no action in flight. Shortly afterward the Amber Hydraulic Low Pressure for the right engine illuminated and the Amber Hydraulic Overheat extinguished. It was also noted that the right engine vibrated briefly when the annunciator illuminated. The checklist for the Amber Right Hydraulic Low Pressure annunciator was performed which indicated no inflight action required unless hydraulics fell in which case flight would have to continue at a lower altitude (FL350 or lower) due to concerns for emergency descents. Due to the rapid occurrence of the two annunciators the decision was made to divert to ZZZ out of an abundance of caution.We landed safely without further issues and Maintenance was sought.The Right Engine Hydraulic pump had failed.
HS 125 Captain reported diverting after a hydraulic system overheat annunciator illuminated during cruise.