As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE ON A TRAINING MISSION, THE PILOT EXPERIENCED LOSS OF NR 1 HYD SYS PRESSURE. THE ACFT RETURNED TO BASE AND LANDED WITHOUT INCIDENT. MX DISCOVERED A CRACKED RIGID HYD LINE, BETWEEN THE CUTOFF BLOCK AND THE 3 WAY SHUTOFF VALVE. CRACK DEVELOPED UNDER A SWAGED FERRULE FITTING.