Learjet 60
Flight Crew Multiengine; Flight Crew Flight Instructor; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Flight Crew Last 90 Days 50; Flight Crew Total 9800; Flight Crew Type 2000
Aircraft Equipment Problem Critical
Flight Crew Diverted; General Declared Emergency
Aircraft
During our descent the pilot flying deployed the spoilers to slow for an ATC speed restriction. Upon stowing of the spoiler lever; the LEFT and RIGHT hydraulic pressure lights began to flash with a corresponding decrease in system pressure as seen on the hydraulic system pressure gauge. Approximately 5 seconds later; the hydraulic system pressure gauge read ZERO pressure; and both the LEFT and RIGHT hydraulic pressure annunciators illuminated steady; indicating a total loss of the aircraft's primary hydraulic system.As the non-flying pilot; I advised ATC of the situation and declared an emergency. I then worked with the pilot flying to accomplish the checklist items in the QRH related to total loss of hydraulic system. We diverted from our intended destination airport and proceeded to a nearby airport where there was adequate runway.The pilot flying made an uneventful landing and we stopped on the runway utilizing the back-up braking system. The aircraft was subsequently towed off the runway.
After both primary hydraulic systems failed during descent the flight crew of a Learjet 60 declared an emergency; performed appropriate checklist actions and diverted uneventfully from their destination airport to a nearby airport with superior runways and facilities.