Narrative:

I was performing night landing currency with runway lights on lowest setting; nearly off. The airport has a road parallel to the runway with a stop sign near the approach end of runway 17. Vehicles at the stop sign face approaching aircraft and block a pilot's view of the VASI. I turned final and mistook the headlights of a truck for the VASI and was concerned about both lights indicating my path high and my altimeter indicating about normal. As I passed the approach end I saw the real VASI; but touched down at runway edge on the grass; rolled to a stop; re-entered runway to exit taxiway. There was no damage to aircraft or pilot. The problem was caused by lack of concentration by pilot. I should have gone around when things were not correct.

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Original NASA ASRS Text

Title: A M20T pilot mistook vehicle headlights on a road at the runway's end for the VASI and landed in the grass beside the runway.

Narrative: I was performing night landing currency with runway lights on lowest setting; nearly off. The airport has a road parallel to the runway with a stop sign near the approach end of Runway 17. Vehicles at the stop sign face approaching aircraft and block a pilot's view of the VASI. I turned final and mistook the headlights of a truck for the VASI and was concerned about both lights indicating my path high and my altimeter indicating about normal. As I passed the approach end I saw the real VASI; but touched down at runway edge on the grass; rolled to a stop; re-entered runway to exit taxiway. There was no damage to aircraft or pilot. The problem was caused by lack of concentration by pilot. I should have gone around when things were not correct.

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.