Narrative:

I called for taxi clearance from the FBO; the first officer was taxiing the aircraft; and; we were initially given runway 22L taxi via Y. Upon crossing runway 33C the controller changed our runway and had us hold short of 22L at P expect 22R. After clearance to cross 22L; we taxied via P to 22R. I then looked down momentarily; to switch from airport diagram page to the departure procedure page of the commercial charts. At that time I noticed that the first officer inadvertently crossed the hold short line for 22R. We did not infringe onto the runway and quickly taxied back across the hold short line. Quarrying the first officer; he was confused by the way the P taxiway was depicted on the commercial airport diagram; he had been using for reference. He was under the impression that P ran parallel to the runway and gave us access to the pad area. After reviewing the diagram; it indeed was a little misleading and my cause some confusing to pilots in the future.

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Original NASA ASRS Text

Title: A Fractional carrier pilot incurred MDW Runway 22L at Taxiway P because he confused Taxiway P direction and believed that it paralleled the Runway.

Narrative: I called for taxi clearance from the FBO; the First Officer was taxiing the aircraft; and; we were initially given runway 22L taxi via Y. Upon crossing Runway 33C the controller changed our Runway and had us hold short of 22L at P expect 22R. After Clearance to cross 22L; we taxied via P to 22R. I then looked down momentarily; to switch from airport diagram page to the departure procedure page of the commercial charts. At that time I noticed that the First Officer inadvertently crossed the hold short line for 22R. We did not infringe onto the runway and quickly taxied back across the hold short line. Quarrying the First Officer; he was confused by the way the P Taxiway was depicted on the commercial airport diagram; he had been using for reference. He was under the impression that P ran parallel to the runway and gave us access to the pad area. After reviewing the diagram; it indeed was a little misleading and my cause some confusing to pilots in the future.

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.