As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
1 OF THE SREWS (P/N AA-2100-11D99)HAD THE HEAD SHEAR OFF JUST UNDER THE HEAD. THIS SCREW, 1 OF 4 HOLD THE FILTER BYPASS DIFFERENTIAL PRESSURE INDICATOR TO THE TOP OF THE FILTER ASSEMBLY. THE AFFECTED SYSTEM WAS THE RUDDER STANDBY. HYDRAULIC FLUID WAS LEAKING STATICLY WITH THE SYSTEM DEPRESSURIZED.