Narrative:

An air carrier B757 to las was on takeoff roll on runway 26R. While scanning the runway I noticed an aircraft taxiing onto the runway at intersection B4. I canceled the B757's takeoff clearance, the air carrier locked his brakes and stopped within about 200 ft from the aircraft (PA24). The B757 spent over an hour letting his brakes cool down. This is the second time in less than a yr an unfamiliar VFR pilot taxied onto runway 26R at B4 intersection in front of a departing B757.

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Original NASA ASRS Text

Title: ATCT LCL CTLR SPOTTED A PA24 TAXIING ONTO RWY 26R AT TXWY B4 AND HOLD AN ACR B757 ON HIS TKOF ROLL TO ABORT HIS TKOF. THE B757 LOCKED HIS BRAKES AND WAS ABLE TO STOP ABOUT 200 FT SHORT OF THE ERRANT PA24.

Narrative: AN ACR B757 TO LAS WAS ON TKOF ROLL ON RWY 26R. WHILE SCANNING THE RWY I NOTICED AN ACFT TAXIING ONTO THE RWY AT INTXN B4. I CANCELED THE B757'S TKOF CLRNC, THE ACR LOCKED HIS BRAKES AND STOPPED WITHIN ABOUT 200 FT FROM THE ACFT (PA24). THE B757 SPENT OVER AN HR LETTING HIS BRAKES COOL DOWN. THIS IS THE SECOND TIME IN LESS THAN A YR AN UNFAMILIAR VFR PLT TAXIED ONTO RWY 26R AT B4 INTXN IN FRONT OF A DEPARTING B757.

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.