As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMB OUT,HYD PRESS DROPPED TO ZERO AND HYD QTY DROPPED TO AUX LEVEL. DURING ABN PROC SYSTEM LEVEL DROPPED WELL BELLOW AUX LEVEL WHEN CONFIGURING TO LAND. FOUND WING SLOT CNTL VALVE IN R. W/W LEAKING AT RETAINING PLUG/STUD. R & R UPPER AND LOWER O-RINGS & PACKING. SLOT CONTROL VALVE INSTALLED IAW MM 27-80-4. OPS AND LEAK CHECK OK. SERVICED HYD SYS. GRND RAN, BLED ALL SYS, ALL OPS.