Narrative:

I was using a DME that was just installed. It was set to olm instead of sea, I thought I was farther from sea VOR than actual. To prevent this, get additional training on new equipment installed in the plane you are using, also xchk with other aids, equipment, etc. I discovered the error by reviewing the sectional chart and immediately descended below the floor of class B airspace. Pilot error.

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Original NASA ASRS Text

Title: PLT WITH NEW DME TUNED TO WRONG STATION (OLM) IS TRACKING IN TO SEA. HE REALIZES HE IS IN THE CLASS B AIRSPACE AT 3500 FT 16 MI S OF THE SEA VOR.

Narrative: I WAS USING A DME THAT WAS JUST INSTALLED. IT WAS SET TO OLM INSTEAD OF SEA, I THOUGHT I WAS FARTHER FROM SEA VOR THAN ACTUAL. TO PREVENT THIS, GET ADDITIONAL TRAINING ON NEW EQUIP INSTALLED IN THE PLANE YOU ARE USING, ALSO XCHK WITH OTHER AIDS, EQUIP, ETC. I DISCOVERED THE ERROR BY REVIEWING THE SECTIONAL CHART AND IMMEDIATELY DSNDED BELOW THE FLOOR OF CLASS B AIRSPACE. PLT ERROR.

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.