As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DEN - RAP, CAPT RETURNED TO THE FIELD DUE TO NR 1 ENG HYD LIGHT ILLUMINATED IN FLIGHT. CAPT ALSO REPORTED, THERE WAS NO HYD QUANTITY INDICATION ON NR 1 HYD SYSTEM. MAINTENANCE FOUND A UNION AT NR 1 HYD MANIFOLD BROKE. AOG FOR PARTS AT THIS TIME. MAINTENANCE INSTALLED NEW UNION.