Narrative:

Returning from pleasure/training flight OQ5, we were vectored in to intercept the ILS approach oak and were cleared for the ILS, switched to oak tower. Our HSI needle was responding and we began the descent from +/-2000 ft. We responded to the gauge indications, but at about 800 ft AGL lost the flag (signal). The tower called us about 700 ft and reported we were 1 mi southwest of the ILS. We then broke out of fog and with the airport in sight, landed ok. Upon landing we determined that the incorrect ILS frequency was set.

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Original NASA ASRS Text

Title: A PA44 PLT ENTERS THE WRONG ILS FREQ RESULTING IN THE ACFT BEING SLIGHTLY OFF COURSE.

Narrative: RETURNING FROM PLEASURE/TRAINING FLT OQ5, WE WERE VECTORED IN TO INTERCEPT THE ILS APCH OAK AND WERE CLRED FOR THE ILS, SWITCHED TO OAK TWR. OUR HSI NEEDLE WAS RESPONDING AND WE BEGAN THE DSCNT FROM +/-2000 FT. WE RESPONDED TO THE GAUGE INDICATIONS, BUT AT ABOUT 800 FT AGL LOST THE FLAG (SIGNAL). THE TWR CALLED US ABOUT 700 FT AND RPTED WE WERE 1 MI SW OF THE ILS. WE THEN BROKE OUT OF FOG AND WITH THE ARPT IN SIGHT, LANDED OK. UPON LNDG WE DETERMINED THAT THE INCORRECT ILS FREQ WAS SET.

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.