Narrative:

A baron called from the north ramp requesting taxi to runway 25L southbound. Unfortunately; I misspoke the runway. The aircraft located on the north ramp should have been issued: 'runway 25R; taxi via a; A11'. I spoke: 'runway 25L; taxi via a; A11'. The baron taxied a; A11; crossed runway 25R onto taxiway B11 and held short of runway 25L where he called the tower ready for departure. The pilot still should not have crossed any runway without a specific instruction to do so. This is a somewhat recent change. Just recently; a clearance to a runway allowed a pilot to cross all runways and taxiways except the runway assigned in the absence of hold short instructions. Apparently; this pilot was not aware of this change. General aviation pilot education may have had the pilot question the controller; or at least have held short of the runway he was encroaching until he received a clearance to cross.

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Original NASA ASRS Text

Title: Tower Controller described an unauthorized runway crossing event during parallel runway departure procedures when misidentifying the departure runway and the pilot apparently unfamiliar with the recent change to taxi procedures.

Narrative: A Baron called from the north ramp requesting taxi to Runway 25L southbound. Unfortunately; I misspoke the runway. The aircraft located on the north ramp should have been issued: 'Runway 25R; taxi via A; A11'. I spoke: 'Runway 25L; taxi via A; A11'. The Baron taxied A; A11; crossed Runway 25R onto Taxiway B11 and held short of Runway 25L where he called the Tower ready for departure. The pilot still should not have crossed any runway without a specific instruction to do so. This is a somewhat recent change. Just recently; a clearance to a runway allowed a pilot to cross all runways and taxiways except the runway assigned in the absence of hold short instructions. Apparently; this pilot was not aware of this change. General Aviation pilot education may have had the pilot question the controller; or at least have held short of the runway he was encroaching until he received a clearance to cross.

Data retrieved from NASA's ASRS site as of April 2012 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.