May 2, 1989
Incident
Minor MINNEAPOLIS, MN
InjuriesNone
Phase of Flight-
ConditionsVMC
OperationFAR 121
Probable Cause
FAILURE OF THE HYDRAULIC POWER TRANSFER UNIT SHUT-OFF (PTU S/O) VALVE DUE TO FAILED (FATIGUED) VALVE BODY ATTACH SCREWS.
NTSB CHI89IA083