SMA IN NIGHT TAXI ENTERS DITCH.

Narrative

TRIP HAD COME UP AT LAST MIN. I HAD ALREADY WORKED A LONG DAY AND TRIED TO DELAY TRIP BUT CUSTOMER REQUIRED AN IMMEDIATE RESPONSE. THE ONLY OTHER TIME I HAD LANDED AT TVR WAS IMMEDIATELY AFTER CONSTRUCTION OF RWY (ORIGINAL APRON) TO DO STOP AND GO LNDG. APPROX 15 NM S OF FIELD I PICKED UP RWY LIGHTS AND A STRING OF COLLISION AVOIDANCE LIGHTS ADJACENT TO RWY 36 THRESHOLD. I NOTICED NO OTHER SUBSTANTIAL LIGHTS IN AREA AND WAS DULY DILIGENT TO STAY ON GLIDE PATH (NO VASI). I LANDED 'STRAIGHT-IN' ON RWY 36 AND TAXIED TO TURNOFF MARKED WITH APPROX 8 BLUE TAXI LIGHTS. IMMEDIATELY AFTER TURNING; AND CLRING THESE LIGHTS I WAS IN TOTAL DARKNESS EXCEPT FOR LNDG LIGHTS. I SLOWLY TAXIED TO TIE-DOWNS USING FBO BUILDING AND A KING AIR FUELING FOR REF. I MET MY PARTY WHO DROVE ME TO THE JOB SITE. UPON COMPLETION WE ATE DINNER RETURNING TO TVR AT APPROX XX30 LCL. DURING OUR DRIVE TO-FROM WE EACH COMMENTED ON HOW DARK IT WAS AND HARD TO SEE. I PROCEEDED TO PREFLT ACFT AT TIE-DOWN WITH ARPT MGR. I STARTED ACFT; VERIFIED FUNCTIONS; AND PROCEEDED TO TAXI. I WAS AGAIN TAKEN WITH HOW DARK IT WAS AND EXERCISED DUE DILIGENCE TO CLR ACFT ON TIE-DOWNS. UPON APCHING TURNOFF TO RWY; I NOTICED A CONGLOMERATION OF REFLECTOR POLES WITH THE AFOREMENTIONED BLUE LIGHTS; NO YELLOW TAXI LINE WAS EVIDENT. WHILE EXECUTING A R TURN ONTO WHAT I THOUGHT WAS TXWY; THE PLANE IMMEDIATELY WENT FORWARD; NOSED-OVER WITH ENG STOPPING. I IMMEDIATELY SHUT OFF SWITCHES; RELEASED SEAT BELT AND EXITED ACFT. PLANE WAS FOUND NOSE DOWN IN APPROX 30 INCH DITCH FACED WITH BROKEN STONE TO L. PROP DAMAGE WAS NOTED TO R WITH WING AGAINST GND AND TAIL 45 DEGS TO GND. SUBSTANTIAL COWLING DAMAGE WAS NOTED TO L SIDE. I PROCEEDED TO FBO AND MET ARPT MGR HALFWAY; BOTH OF US VERIFIED STABILITY OF ACFT. CONTACTED EMER RESPONSE. PLANE WAS RIGHTED AND SECURED. SUBSTANTIAL PROP AND NOSE GEAR DAMAGE WAS NOTED; ALL DAMAGES FORWARD OF FIREWALL. OBVIOUSLY BEING TIRED DID NOT HELP NIGHT VISION; ESPECIALLY AT A FIELD NEW TO PLT. TAXI LIGHTS ON TXWY AND IMMEDIATELY ADJACENT TO RAMP WOULD HAVE GREATLY HELPED. THE EXISTING REFLECTORS-LIGHTS CREATED AN ILLUSION OF A TXWY. THE PLT I CONTACTED TO PICK ME UP ALSO COMMENTED ON THE INTENSE DARKNESS AND NONSTANDARD MARKINGS AS DID THE ARPT MGR. EVIDENTLY OTHER PLTS HAVE COME CLOSE TO DOING SAME. OBVIOUSLY POSTPONING THE FLIGHT WOULD PROBABLY HAVE NEGATED THIS INCIDENT; BUT WAS NOT AN OPTION. MOREOVER; AS I HAD LOGGED OVER 500 NIGHT HRS BOTH IFR-VFR AND EXECUTED 500 PLUS NIGHT LNDGS AT OTHER ARPTS; I DID NOT FEEL THIS WOULD RESULT IN THIS KIND OF PROB. THE INCIDENT OCCURRED SO RAPIDLY THAT IT WAS OVER BEFORE I FIGURED OUT WHAT HAPPENED. I LATER RETURNED TO TVR AND FOUND ARPT PERSONNEL MODIFYING TXWY MARKINGS; TO BETTER DELINEATE TXWY. ALSO ON BACK IS DIAGRAM SHOWING ARRANGEMENT OF TXWY-APRON-RWY; NOTE TAXI STUB-OUTS WHICH ADDED TO ILLUSION OF ASPHALT IN FRONT OF ME.