GA SMA LONG LNDG AND RWY EXCURSION CAUSING MINOR ACFT DAMAGE.

Narrative

ON A VFR FLT FROM BERMUDA DUNES TO FULLERTON; I WAS CLRED BY THE TWR CTLR TO FLY A STRAIGHT IN APCH TO RWY 24. THE APCH WAS UNEVENTFUL; BUT AS I APCHED THE SHORT FINAL; TFC THAT HAD BEEN CLRED TO LAND AHEAD OF ME DID NOT CLR THE RWY; AND I WAS INSTRUCTED TO 'GO AROUND.' I EXECUTED THE GO AROUND PROC. ON RIGHT DOWNWIND; 1100' AGL; ABOUT MIDFIELD; THE CTLR INSTRUCTED ME TO 'MAKE A SHORT APCH.' I ALWAYS TRY TO COMPLY WITH THE CTLR'S REQUESTS AND DID ON THIS OCCASION AS WELL; TURNING RIGHT AT THE RWY 24 THRESHOLD; AND MAKING A SHORT APCH. I APPARENTLY MISCALCULATED THE SHORTNESS OF THE APCH; AND CAME IN TOO HOT; TOUCHED DOWN BEFORE MIDFIELD; AND WAS UNABLE TO STOP IN TIME. I WAS ABLE TO MAKE A LEFT TURN; BUT SKIDDED OFF INTO THE GRAVEL AT THE END OF RWY 24; KNOCKING DOWN A SIGN AND A LIGHTED DIRECTIONAL BOX. I STOPPED ABOUT 10' PAST THE END OF THE RWY. THE ENG WAS STILL RUNNING; AND THERE WAS AT THE TIME NO APPARENT DAMAGE TO THE ACFT. I TAXIED OUT OF THE GRAVEL TO THE RUNUP AREA SHUT DOWN; AND EXAMINED THE ACFT. OTHER THAN SOME BLACK MARKS ON THE RIGHT WHEEL PANT; AND THE TIP OF THE PROPELLER; THERE APPEARED TO BE NO SIGNIFICANT DAMAGE. THE CONTRIBUTING FACTORS WERE AS FOLLOWS. THE TEMP WAS 103 DEG; INDICATING A DENSITY ALT OF 2821'. THE FIELD ELEVATION IS 93'. THE ONLY RWY AT FULLERTON IS ONLY 3200' LONG; PLENTY FOR NORMAL OPS; BUT THERE IS LITTLE MARGIN FOR ERROR ON HOT DAYS; LARGER TWINS; ETC. I WAS IN AN SMA. I HAD SELECTED 20 DEG FLAPS FOR THE LNDG; BUT THE FLAPS APPARENTLY DID NOT COME DOWN. THE CTLR FROM THE TWR SAID THAT HE HAD NOTICED ONLY ONE NOTCH OF FLAPS; BUT THE FLAPS APPEARED TO START DOWN AGAIN WHILE I WAS ON THE RWY. I CANNOT VERIFY THIS; BUT THERE MAY HAVE BEEN FLAP MALFUNCTION. THIS COULD EASILY HAVE RESULTED IN MY NOT BEING ABLE TO STOP IN TIME. HUMAN PERFORMANCE CONSIDERATIONS WERE AS FOLLOWS. WHEN THE CTLR ASKED ME TO 'MAKE A SHORT APCH;' I SHOULD HAVE JUST SAID 'UNABLE;' RATHER THAN TRYING TO ACCOMMODATE HIM WITH GRIEVOUS RESULTS. AS THE PIC; I AM RESPONSIBLE FOR THE SAFE CONDUCT OF THE FLT; AND CANNOT LET ANYTHING GET IN THE WAY OF THAT. I WAS NOT AWARE OF THE POSSIBLE FLAP MALFUNCTION. PEOPLE OFTEN RELY ON UNCONSCIOUS PERCEPTIONS; WHETHER OR NOT SOMETHING 'FEELS RIGHT.' THIS CAN EASILY LEAD TO AN ACCIDENT.