Incident Overview
A crew operating a flight from Minneapolis–Saint Paul International Airport (MSP) to San Francisco International Airport (SFO) reported a decrease in climb rate while over Rapid City, South Dakota, at flight level 310. The pilot noted that fuel burn was approximately 1,400 pounds ahead of schedule. An in-flight inspection revealed that the inboard trailing edge flaps had failed to retract properly after takeoff and remained extended at a 7-degree down position.
Return and Landing
The flight returned to Minneapolis and landed at 1540 CDT, roughly 50 minutes after the initial incident. A post-flight inspection disclosed that the inboard flap control valve had failed. The crew stated that this malfunction had occurred on a previous flight and had been reported. On both occasions, the flaps had ground-checked satisfactorily.
Maintenance Action
Republic Airlines maintenance corrected the reported failure by replacing a flap control valve and inspecting the rigging in accordance with Boeing Maintenance Manual 27-51-51.