Narrative:

Fri, usually busy, but during a dead period medium large transport had taxied out to runway 13L. Our ground controller taxied small aircraft, from the air carrier ramp to the intersection of runway 13L and taxiway delta. This intersection is the closest one to that ramp. Medium large transport was issued departure clearance on runway 13L. The aircraft was still about 200' short of the runup area and right turn for the runway. During scan I noted an small aircraft crossing runway 13L, approximately 1500' down the runway (the aircraft was on taxiway D). I queried the ground control position as to the location of the departure, as indicated by the proposed departure strip. The small aircraft was well clear of runway 13L as medium large transport began departure roll. The small aircraft pilot was told to stop. When queried the pilot of the small aircraft indicated that she was alone (no instrument on board). I am uncertain if she was a student or perhaps a low-time private pilot. She was quite unfamiliar and did not mention it or request any assistance. This unfamiliarity is emphasized when details for taxi runway 13L at intersection D were reissued, 'make a 180 and hold short of runway 13L; contact tower for departure.' the small aircraft pilot taxied back out onto runway 13L and stopped. She then asked ground control if she should hold short of the runway. She was already on it--at least 30' past the bold yellow hold lines. No traffic at all yet. We took her up to runway 18. This occurred with only 2 aircraft on frequency and moving. We were very fortunate--this time! The pilot was talked to and perhaps we helped her a bit. I personally believe she learned from these mistakes and the ensuing discussions.

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Original NASA ASRS Text

Title: ACFT TAXIED ONTO AN ACTIVE RWY WITHOUT ATC CLRNC.

Narrative: FRI, USUALLY BUSY, BUT DURING A DEAD PERIOD MLG HAD TAXIED OUT TO RWY 13L. OUR GND CTLR TAXIED SMA, FROM THE ACR RAMP TO THE INTXN OF RWY 13L AND TXWY DELTA. THIS INTXN IS THE CLOSEST ONE TO THAT RAMP. MLG WAS ISSUED DEP CLRNC ON RWY 13L. THE ACFT WAS STILL ABOUT 200' SHORT OF THE RUNUP AREA AND RIGHT TURN FOR THE RWY. DURING SCAN I NOTED AN SMA XING RWY 13L, APPROX 1500' DOWN THE RWY (THE ACFT WAS ON TXWY D). I QUERIED THE GND CTL POS AS TO THE LOCATION OF THE DEP, AS INDICATED BY THE PROPOSED DEP STRIP. THE SMA WAS WELL CLR OF RWY 13L AS MLG BEGAN DEP ROLL. THE SMA PLT WAS TOLD TO STOP. WHEN QUERIED THE PLT OF THE SMA INDICATED THAT SHE WAS ALONE (NO INSTR ON BOARD). I AM UNCERTAIN IF SHE WAS A STUDENT OR PERHAPS A LOW-TIME PVT PLT. SHE WAS QUITE UNFAMILIAR AND DID NOT MENTION IT OR REQUEST ANY ASSISTANCE. THIS UNFAMILIARITY IS EMPHASIZED WHEN DETAILS FOR TAXI RWY 13L AT INTXN D WERE REISSUED, 'MAKE A 180 AND HOLD SHORT OF RWY 13L; CONTACT TWR FOR DEP.' THE SMA PLT TAXIED BACK OUT ONTO RWY 13L AND STOPPED. SHE THEN ASKED GND CTL IF SHE SHOULD HOLD SHORT OF THE RWY. SHE WAS ALREADY ON IT--AT LEAST 30' PAST THE BOLD YELLOW HOLD LINES. NO TFC AT ALL YET. WE TOOK HER UP TO RWY 18. THIS OCCURRED WITH ONLY 2 ACFT ON FREQ AND MOVING. WE WERE VERY FORTUNATE--THIS TIME! THE PLT WAS TALKED TO AND PERHAPS WE HELPED HER A BIT. I PERSONALLY BELIEVE SHE LEARNED FROM THESE MISTAKES AND THE ENSUING DISCUSSIONS.

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.