Narrative:

There was apparently an unauthorized and accidental incursion into class B airspace on takeoff from north las vegas airport. It seems to have been caused by a directional gyroscope that ceased working and an inaccurate or inoperative altitude indicator. Both are being checked. The directional gyroscope had previously been precessing some, but totally failed on takeoff. The altitude indicator is as yet undiagnosed and came without warning.

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Original NASA ASRS Text

Title: MOONEY M20 ACFT CLBING FROM VGT ENTERED LAS CLASS B AIRSPACE. RPTR PLT CLAIMS MULTIPLE FAILURES, DIRECTIONAL GYROSCOPE AND ALTIMETER.

Narrative: THERE WAS APPARENTLY AN UNAUTH AND ACCIDENTAL INCURSION INTO CLASS B AIRSPACE ON TKOF FROM NORTH LAS VEGAS ARPT. IT SEEMS TO HAVE BEEN CAUSED BY A DIRECTIONAL GYROSCOPE THAT CEASED WORKING AND AN INACCURATE OR INOP ALT INDICATOR. BOTH ARE BEING CHKED. THE DIRECTIONAL GYROSCOPE HAD PREVIOUSLY BEEN PRECESSING SOME, BUT TOTALLY FAILED ON TKOF. THE ALT INDICATOR IS AS YET UNDIAGNOSED AND CAME WITHOUT WARNING.

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.