As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ROC - FLT 2274 - UPON GEAR RETRACTION ON TAKEOFF, A-SYSTEM QUANTITY WENT TO ZERO AND A-SYSTEM LOW PRESSURE LIGHTS CAME ON. FLIGHT RETURNED TO ROC WHERE LANDING WAS WITHOUT FURTHER INCIDENT. MAINTENANCE FOUND HYDRAULIC LINE LEAKING AT RT MAIN GEAR UPLOCK CYCLINDER. REPLACED LINE. (W)