Narrative:

Taxiing out of big bears terminal area I approached what I assumed was the taxiway to runway (08?) (07). I looked closely for runway signs or the hold short stripes and seeing none I taxied onto what I thought was the taxiway leading to the runway. As I taxied out I heard an aircraft announce it was taking off on runway 08 (07). I instinctively looked down toward the runway end as I made the turn onto what turned out to be the runway. There is a mild rise at the approach end of runway 08 which still made it confusing as to whether the aircraft and I were on the same concrete. Within seconds the aircraft topped the rise and there was no question I was on the runway. I taxied the left main into the dirt on the side of the runway while the twin was airborne at 30 ft and passed approximately 10 ft off to the left. I rapidly did a 180 degree turn and taxied off the runway. This time paying particular attention to see if there were any markings of an active runway, I noted that there were no signs but that a yellow runway hold short line had been painted on the taxiway. This line, except at the edges had been covered with dirt and dust to the point where it was all but unseeable. (There is no instrument approach to big bear.) I feel there is potential for future runway incursions at airports where: taxi and runway painted markings are not cleaned and repainted at regular intervals. Runway and taxiway signs are (not) clearly posted.

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Original NASA ASRS Text

Title: NMAC AFTER UNAUTH RWY ENTRY OP AT A NON TWR ARPT.

Narrative: TAXIING OUT OF BIG BEARS TERMINAL AREA I APCHED WHAT I ASSUMED WAS THE TXWY TO RWY (08?) (07). I LOOKED CLOSELY FOR RWY SIGNS OR THE HOLD SHORT STRIPES AND SEEING NONE I TAXIED ONTO WHAT I THOUGHT WAS THE TXWY LEADING TO THE RWY. AS I TAXIED OUT I HEARD AN ACFT ANNOUNCE IT WAS TAKING OFF ON RWY 08 (07). I INSTINCTIVELY LOOKED DOWN TOWARD THE RWY END AS I MADE THE TURN ONTO WHAT TURNED OUT TO BE THE RWY. THERE IS A MILD RISE AT THE APCH END OF RWY 08 WHICH STILL MADE IT CONFUSING AS TO WHETHER THE ACFT AND I WERE ON THE SAME CONCRETE. WITHIN SECONDS THE ACFT TOPPED THE RISE AND THERE WAS NO QUESTION I WAS ON THE RWY. I TAXIED THE L MAIN INTO THE DIRT ON THE SIDE OF THE RWY WHILE THE TWIN WAS AIRBORNE AT 30 FT AND PASSED APPROX 10 FT OFF TO THE L. I RAPIDLY DID A 180 DEG TURN AND TAXIED OFF THE RWY. THIS TIME PAYING PARTICULAR ATTN TO SEE IF THERE WERE ANY MARKINGS OF AN ACTIVE RWY, I NOTED THAT THERE WERE NO SIGNS BUT THAT A YELLOW RWY HOLD SHORT LINE HAD BEEN PAINTED ON THE TXWY. THIS LINE, EXCEPT AT THE EDGES HAD BEEN COVERED WITH DIRT AND DUST TO THE POINT WHERE IT WAS ALL BUT UNSEEABLE. (THERE IS NO INSTRUMENT APCH TO BIG BEAR.) I FEEL THERE IS POTENTIAL FOR FUTURE RWY INCURSIONS AT ARPTS WHERE: TAXI AND RWY PAINTED MARKINGS ARE NOT CLEANED AND REPAINTED AT REGULAR INTERVALS. RWY AND TXWY SIGNS ARE (NOT) CLRLY POSTED.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.