What was found
SATURDAY, AUGUST 22, 2009, FLIGHT 7F805 ATR42 ACFT REGISTRATION SHORTLY AFTER TAKEOFF, EXPERIENCED FUMES/ELECTRICAL ODOR IN THE COCKPIT. THE FO’S AIRSPEED INDICATOR BEGAN TO MALFUNCTION, SOON AFTER THE CREW RECEIVED AN OVER SPEED WARNING AND FLIGHT INSTRUMENTS BEGAN TO MALFUNCTION. THE CREW RETURNED THE ACFT TO DEPARTURE. THE LANDING WAS UNEVENTFUL. MX CREW FOUND FAULT WITH THE NR 1 INVERTER. NVERTER WAS REPLACED AND THE ACFT WAS RETURNED TO SERVICE.