What was found
HYD 'A' FLUID LEVEL DROPPED TO 2.0 GAL DURING FLIGHT AND PASSENGERS REPORTED SMELLING FUMES NEAR/IN SEATS OVERWING AREA. ALT FLAPS AND MANUAL GEAR USED. A/C ARRIVED AT GATE WITH HYD QTY 3.75 GAL. SERVICED HYD TO FULL, 1 GAL ADDED. INSPECTED NOSE AND MAIN GEAR AND WING SLATS AND FLAPS AND RUDDER. RAN ENGS NR 1 AND NR 2 CKD HYD LINES FOUND OK. WITH NEGS RUNNING, NO SMELL IN CABIN.