Narrative:

I was in the tower for familiarity time. Aircraft X called for a VFR clearance; which was then formulated and issued. After read back; the aircraft requested and received a taxi clearance from the ramp to runway 5. While the aircraft was taxiing; the three of us in the tower discussed the proper identifier for [their destination]; since it is a source of confusion with the other [airports in the same city]. When we looked back at the aircraft; approximately 15 seconds later; it was observed holding at runway edge; well past the hold line. The pilot acknowledged his error and was allowed to hold there since he was the only active traffic. A moment later he advised ready for departure and was cleared. When he was switched to departure; he conveyed some sort of apology for the error and then left the frequency.this point on the airport is a well known source of runway incursions. Aircraft taxiing off the ramp in that direction have been inadvertently taxiing across the runway 5 hold line for years and there have been multiple (dozens?) of incursions there. Incursions have involved a varied mix of experience; professional pilots; hobbyists; fixed-wing; and helicopters. The intersection has been heavily modified to prevent errors including twice reconstructing the intersection to make it less confusing; adding runway identification pavement markings; and installing runway guard lights. The hold point used to be identified as an airport hot spot on the diagram; but that was removed after the latest reconstruction project was completed last fall. I don't have a recommendation to make; I'm out of ideas.

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Original NASA ASRS Text

Title: AZO Tower Controller reported a Cessna aircraft held short of Runway 5; but across the hold short line. The reporter states this is a recurring problem at this location.

Narrative: I was in the Tower for familiarity time. Aircraft X called for a VFR clearance; which was then formulated and issued. After read back; the aircraft requested and received a taxi clearance from the ramp to Runway 5. While the aircraft was taxiing; the three of us in the Tower discussed the proper identifier for [their destination]; since it is a source of confusion with the other [airports in the same city]. When we looked back at the aircraft; approximately 15 seconds later; it was observed holding at runway edge; well past the hold line. The pilot acknowledged his error and was allowed to hold there since he was the only active traffic. A moment later he advised ready for departure and was cleared. When he was switched to departure; he conveyed some sort of apology for the error and then left the frequency.This point on the airport is a well known source of runway incursions. Aircraft taxiing off the ramp in that direction have been inadvertently taxiing across the Runway 5 hold line for years and there have been multiple (dozens?) of incursions there. Incursions have involved a varied mix of experience; professional pilots; hobbyists; fixed-wing; and helicopters. The intersection has been heavily modified to prevent errors including twice reconstructing the intersection to make it less confusing; adding runway identification pavement markings; and installing runway guard lights. The hold point used to be identified as an airport Hot Spot on the diagram; but that was removed after the latest reconstruction project was completed last fall. I don't have a recommendation to make; I'm out of ideas.

Data retrieved from NASA's ASRS site 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.