scope:

Description of Driving Event:

Hydraulic fluid leakage was noted at the interface of the flex hose and Rosan fitting on a hydraulic pump. The fittings were a different size at each end of the flex hose. Different size fittings require different torque values, which the specifications did not identify. The hydraulic system is inspected prior to each mission of the shuttle vehicle. Review of the procedure used during installation of the hydraulic system shows that one end of the flex hose was torqued to 120 foot pounds. The installation drawing does not specify that the other end of the flex hose has a smaller fitting that should require a lower torque. Leakage was corrected by a hose replaced and torqued properly.