Narrative:

On approach to ont, at first contact was told to make straight in to runway 26L, and cleared for descent. During descent was told to stop descent at 4000 ft, was then told traffic was no factor. I continued descent and approach. I heard nothing further from approach. At approximately 4 mi from the airport I told my position to approach and was then told I had been advised to make right traffic to the runway. I never heard that instruction nor was there any other communication from approach. I think the problem is controllers not making sure (or having any responsibility) that pilots do in fact hear and understand instructions.

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Original NASA ASRS Text

Title: A PVT PLT FLYING A C182 INTO ONT RPTS CONFUSION AND A POSSIBLE MISUNDERSTANDING WITH ATC INSTRUCTIONS.

Narrative: ON APCH TO ONT, AT FIRST CONTACT WAS TOLD TO MAKE STRAIGHT IN TO RWY 26L, AND CLRED FOR DSCNT. DURING DSCNT WAS TOLD TO STOP DSCNT AT 4000 FT, WAS THEN TOLD TFC WAS NO FACTOR. I CONTINUED DSCNT AND APCH. I HEARD NOTHING FURTHER FROM APCH. AT APPROX 4 MI FROM THE ARPT I TOLD MY POS TO APCH AND WAS THEN TOLD I HAD BEEN ADVISED TO MAKE R TFC TO THE RWY. I NEVER HEARD THAT INSTRUCTION NOR WAS THERE ANY OTHER COM FROM APCH. I THINK THE PROB IS CTLRS NOT MAKING SURE (OR HAVING ANY RESPONSIBILITY) THAT PLTS DO IN FACT HEAR AND UNDERSTAND INSTRUCTIONS.

Data retrieved from NASA's ASRS site as of July 2007 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.