PLT OF AN ATX SMT ACFT OPERATED THE ACFT IN AN UNAIRWORTHY CONDITION WITH KNOWN WING LEADING EDGE DAMAGE.

Narrative

I WAS PIC OF AN SMT TWIN ON AN AIR TAXI FLT FROM PORTLAND; ME; TO LEBANON; NH; ON DEC/XX/92. THE FLT WAS CONDUCTED UNDER AN IFR FLT PLAN. I WAS CLRED FOR A VOR A APCH TO LEBANON ARPT. I HAD CROSSED THE VOR AT 4000 FT AND HAD PROCEEDED OUTBOUND AND COMPLETED THE PROC TURN INBOUND. I HAD ESTABLISHED THE INBOUND COURSE AND WAS DSNDING TO 3000 FT TO WAIT TO CROSS THE HANOVER MARKER BEACON; TO THEN DSND. WHILE AT 3000 FT; I HEARD A LOUD BANG AND SLIGHT SHUDDER OF THE ACFT. THE ACFT FLEW NORMALLY AND I THOUGHT I HAD THROWN ICE FROM A PROP BLADE. A NORMAL APCH AND LNDG WAS MADE. AFTER DISCHARGING MY PAX; I DID A CIRCLE CHK OF THE ACFT. IT WAS THEN I FOUND A TEAR INTO THE WING SKIN ON THE L WING BTWN THE FUSELAGE AND THE ENG NACELLE. THIS TEAR WAS ON THE LEADING EDGE OF THE WING AND WENT INTO THE WING APPROX 4 INCHES; I TOOK A FLASHLIGHT AND EXAMINED INTO THE WING. I COULD EASILY SEE ALL WIRES AND LINES IN THE WING AND DETERMINED THAT NONE WERE DAMAGED; FRAYED OR DISTURBED. I THEN RAN THE L ENG AND ALL ACCESSORIES ON THE L WING (LIGHTS; GAUGES; ETC) AND DETERMINED THAT ALL WERE WORKING NORMALLY. I COULD HEAR THE FUEL PUMP WORKING ALSO. I DOUBLECHKED TO SEE THAT THERE WERE NO FUEL LEAKS. I THEN USED DUCT TAPE TO CLOSE THE TEAR IN THE WING. AFTER A THOROUGH RUNUP I PROCEEDED ON AN IFR FLT PLAN BACK TO LEWISTON; ME. I BELIEVE THAT THE GASH WAS CAUSED BY FAIRLY STRONG WINDS BLOWING OVER THE MOUNTAINS MAY HAVE CARRIED TREE BRANCHES INTO THE AIR. OTHER THAN THE DAMAGED WING AND IMPACT DENTS ON L STABILIZER; NO OTHER MARKS WERE ON ACFT. MANY ANTENNAS AND LIGHTS ON BELLY OF FUSELAGE WHICH ARE LOWER THAN IMPACT AREA WERE UNTOUCHED. I MUST EMPHASIZE THAT THE ACFT PERFORMED NORMALLY BOTH BEFORE AND AFTER THE IMPACT WAS FELT. USING THE DUCT TAPE; THE WING GASH WAS COMPLETELY COVERED BACK TO THE ORIGINAL SHAPE OF THE WING. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR HAS RECEIVED LETTER OF INVESTIGATION FROM THE FAA CONCERNING THIS INCIDENT. THOUGHT THAT PROP SPINNER ICE MAY HAVE BROKEN OFF IN A LARGE CHUNK AND CAUSED ACFT WING LEADING EDGE DAMAGE. HE DOES NOT HAVE AN A&P MECHS CERTIFICATE. NOR DID HE CHK WITH THE OPERATOR'S DIRECTOR OF MAINT FOR APPROVAL TO OPERATE THE ACFT WITH THE TEMPORARY REPAIR OF THE 'DUCT TAPE.'