As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CLE FLIGHT#4015 THE CREW REPORTED THE #1 HYDRAULIC SYSTEM INDICATED ZERO QUANTITY IN FLIGHT.THE AIRCRAFT RETURNED TO CLEVELAND AND LANDED WITHOUT FURTHER INCIDENT.MAINTENANCE INSPECTED AND FOUND THE RIGHT WING SPOILER ACTUATOR LEAKING.THE ACTUATOR WAS REPLACED AND OPERATIONAL CHECKS WERE GOOD.THE AIRCRAFT WAS RELEASED FOR SERVICE.