Narrative:

As the assistant chief of a part 141 school; I was conducting an annual part 141 instructor check ride. I asked for a simulated emergency approach and landing from pattern altitude. The CFI flying the airplane was to perform the maneuver and instruct at the same time. I noticed that the turn to the runway was late but by holding flap extension to 10 degrees and flying a tight pattern; it appeared we would make the runway. A road crosses at the end of the runway and as we passed over the road; a van was directly beneath us and the right tire contacted the roof of the van. I felt a bump but did not see the vehicle which came from the right side. The landing was uneventful. The aircraft sustained no damage but subsequently a van came to the refueling pumps and we were shown a damaged spot on the roof of the van where the tire hit. There were no injuries. The cause of this incident was a poor approach pattern followed by a low and slow approach on final leading to a sink rate greater than expected. I should have intervened and called for power and a go around as soon as I noticed a poor pattern and not allowed this simulated maneuver to turn into a real incident.

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Original NASA ASRS Text

Title: A PLT RECEIVING AN INSTRUCTOR'S CHK RIDE DID AN UNINTENTIONAL LOW APCH AND AN ACFT TIRE CONTACTED A VEHICLE ROOF ON SHORT FINAL.

Narrative: AS THE ASSISTANT CHIEF OF A PART 141 SCHOOL; I WAS CONDUCTING AN ANNUAL PART 141 INSTRUCTOR CHK RIDE. I ASKED FOR A SIMULATED EMER APCH AND LNDG FROM PATTERN ALT. THE CFI FLYING THE AIRPLANE WAS TO PERFORM THE MANEUVER AND INSTRUCT AT THE SAME TIME. I NOTICED THAT THE TURN TO THE RWY WAS LATE BUT BY HOLDING FLAP EXTENSION TO 10 DEGS AND FLYING A TIGHT PATTERN; IT APPEARED WE WOULD MAKE THE RWY. A ROAD CROSSES AT THE END OF THE RWY AND AS WE PASSED OVER THE ROAD; A VAN WAS DIRECTLY BENEATH US AND THE R TIRE CONTACTED THE ROOF OF THE VAN. I FELT A BUMP BUT DID NOT SEE THE VEHICLE WHICH CAME FROM THE R SIDE. THE LNDG WAS UNEVENTFUL. THE ACFT SUSTAINED NO DAMAGE BUT SUBSEQUENTLY A VAN CAME TO THE REFUELING PUMPS AND WE WERE SHOWN A DAMAGED SPOT ON THE ROOF OF THE VAN WHERE THE TIRE HIT. THERE WERE NO INJURIES. THE CAUSE OF THIS INCIDENT WAS A POOR APCH PATTERN FOLLOWED BY A LOW AND SLOW APCH ON FINAL LEADING TO A SINK RATE GREATER THAN EXPECTED. I SHOULD HAVE INTERVENED AND CALLED FOR PWR AND A GAR AS SOON AS I NOTICED A POOR PATTERN AND NOT ALLOWED THIS SIMULATED MANEUVER TO TURN INTO A REAL INCIDENT.

Data retrieved from NASA's ASRS site as of January 2009 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.