Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Critical
Flight Crew Overcame Equipment Problem; General Maintenance Action
Procedure; Aircraft
[During approach] the slats failed to deploy on first attempt. Slats did deploy after QRH checklist procedure was competed. A normal flaps five landing was accomplished. The aircraft was returned to service: 'message cleared. No defects noted. A/C found to be in transitory condition.' On [the next] flight the Slats again failed to deploy on first attempt; but the slats deployed subsequent to QRH checklist procedure. Maintenance found possible electrical faults in SF-ACE one and/or the slat/flap deployment lever. FDR's were pulled in accordance with NTSB reportable event requirements.
EMB175 Captain reports failure of slats to extend when selected during approach. After QRH procedure (return flap lever to previous position) the flaps and slats extend normally. Maintenance can find no faults. The anomaly repeats on the next leg with the same outcome. This time Maintenance detected possible faults in the Flap/slat computer or the flap lever.