As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED THAT AFTER LANDING GEAR RETRACTION RECEIVED A HYDRAULIC SYSTEM 1 LOW QUANTITY MESSAGE. THE CREW CONTINUED TO MONITOR THE HYDRAULIC SYSTEM DURING THE FLIGHT. THE LEVELS CONTINUED TO DROP. AN EMERGENCY WAS DECLARED BY CHARLESTON APPROACH. THE AIRCRAFT LANDED WITHOUT INCIDENT. CREW REPORTED THAT THEY DID NOT LOSE CONTROL OF ANY FLIGHT CONTROL SYSTEMS. MAINTENANCE SERVICED THE HYDRAULIC SYSTEM 1 TO ITS FULL QUANTITY AND PERFORMED LEAK CHECKS. NO LEAKS WERE NOTED. OPERATIONAL CHECKS OF THE HYDRAULIC SYSTEM WERE GOOD WITH NO FURTHER DEFECTS NOTED.