Narrative:

While sbound from osh, passing east of class C airspace, the over-voltage light illuminated and would not go out when master switch was reset. Turning master switch off and on reset GPS, which takes 20 seconds to reset. When it recovered, the GPS showed 19.8 NM from center of class C, placing the aircraft in the outer ring. I then contacted approach while correcting course to the edge of class C. No known conflict occurred. The event occurred due to the combination of the following: the planned route's nearness of the class C airspace, the timing of the electrical problem as convergence with class C was becoming more critical, and the distraction of troubleshooting the problem and eliminating the electrical load.

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Original NASA ASRS Text

Title: SMA PLT ENTERS CLASS C AIRSPACE WITHOUT CLRNC DUE TO TEMPORARY LOSS OF ELECTRICAL PWR TO GPS.

Narrative: WHILE SBOUND FROM OSH, PASSING E OF CLASS C AIRSPACE, THE OVER-VOLTAGE LIGHT ILLUMINATED AND WOULD NOT GO OUT WHEN MASTER SWITCH WAS RESET. TURNING MASTER SWITCH OFF AND ON RESET GPS, WHICH TAKES 20 SECONDS TO RESET. WHEN IT RECOVERED, THE GPS SHOWED 19.8 NM FROM CTR OF CLASS C, PLACING THE ACFT IN THE OUTER RING. I THEN CONTACTED APCH WHILE CORRECTING COURSE TO THE EDGE OF CLASS C. NO KNOWN CONFLICT OCCURRED. THE EVENT OCCURRED DUE TO THE COMBINATION OF THE FOLLOWING: THE PLANNED ROUTE'S NEARNESS OF THE CLASS C AIRSPACE, THE TIMING OF THE ELECTRICAL PROB AS CONVERGENCE WITH CLASS C WAS BECOMING MORE CRITICAL, AND THE DISTR OF TROUBLESHOOTING THE PROB AND ELIMINATING THE ELECTRICAL LOAD.

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.