What was found
FLIGHT 4157 WAS EN ROUTE TO DCA AND RECEIVED A AMBER CAS MESSAGE INDICATING A STANDBY HYDRAULIC FAILURE. THE CREW CHECKED THE HYDRAULIC PAGE WHICH ONLY HAD DASHES ON IT. THE CREW REFERENCED THE QUICK REFERENCE HANDBOOK AND CALLED MAINTENANCE CONTROL. FLIGHT 4157 DIVERTED TO IAD BECAUSE OF THE LONGER RUNWAY. THE CREW DECLARED AN EMERGENCY AND PERFORMED A NO FLAP LANDING AT IAD WITH NO FURTHER INCIDENTS. MAINTENANCE SENT A MECHANIC AND PARTS TO IAD TO INSPECT THE AIRCRAFT. MAINTENANCE RERACKED THE FLAP CONTROL BOX, PERFORMED SEVERAL GEAR EXTENSIONS, SEVERAL FLAP CYCLES, AND ALL APPLICABLE OPERATIONAL TESTS WITH NO FURTHER INCIDENTS. THE AIRCRAFT WAS THEN RELEASED FOR SERVICE.