Narrative:

I planned a trip to ZZZ. I did file a flight plan and I had flight following the whole way. Weather.gov reported 1/4 inch rain and when I called flight service and pulled flight plan and duats; they did not mention 4 inches of rain overnight. First I did a fly over and then we touched down about 100 ft beyond the 2 rocks at about 70MPH. Dropped the nose gear and immediately lifted the nose to slow airplane down; we hit a large dip on the grassy runway and the plane bounced up 3-5 ft in the air. I pushed the nose down and applied full brakes at that time; the brakes locked and we were not slowing down (sheriff measured 605 foot skid). Hydroplaning and floating over the wet grass. I could see 3 cars in the road ahead between the runway and another grassy portion; we needed another 20 or 30 ft at that time. Two cars pulled up and the truck just stayed put! He looked up and just froze! I maneuvered to the right and almost missed him; but my left wing hit his passenger door; my plane did a 180 and came to rest on the other side. No injuries.

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Original NASA ASRS Text

Title: General aviation pilot reported going off the end of runway and striking a vehicle on the road at the end. The runway was grass and recently received a lot of rain.

Narrative: I planned a trip to ZZZ. I did file a flight plan and I had flight following the whole way. Weather.gov reported 1/4 inch rain and when I called flight service and pulled flight plan and DUATS; they did not mention 4 inches of rain overnight. First I did a fly over and then we touched down about 100 FT beyond the 2 rocks at about 70MPH. Dropped the nose gear and immediately lifted the nose to slow airplane down; we hit a large dip on the grassy runway and the plane bounced up 3-5 FT in the air. I pushed the nose down and applied full brakes at that time; the brakes locked and we were not slowing down (sheriff measured 605 foot skid). Hydroplaning and floating over the wet grass. I could see 3 cars in the road ahead between the runway and another grassy portion; we needed another 20 or 30 FT at that time. Two cars pulled up and the truck just stayed put! He looked up and just froze! I maneuvered to the right and almost missed him; but my left wing hit his passenger door; my plane did a 180 and came to rest on the other side. No injuries.

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.