Narrative:

On an IFR flight from hilton head island, sc (hxd) to chapel hill, nc (igx), I first became aware of a glitch in the altimeter readings when I observed intermittently during the climb that there was an occasional 'skip' in the vertical speed indicator. It seemed to correct as I leveled at 15000 ft, the assigned cruise altitude. Yet, out of concern about the altimeter, approaching a level of IMC which was slightly higher than my cruise altitude and, with a forecast of VFR WX ahead and visual cues that it was improving, I asked for a block to climb to 16000 ft to keep me in VFR conditions over the cloud level.

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Original NASA ASRS Text

Title: BEECH CRAFT PLT HAS PITOT STATIC PROBS. USES ATC ASSISTANCE AND DIVERTS TO ARPT WITH LONG RWY.

Narrative: ON AN IFR FLT FROM HILTON HEAD ISLAND, SC (HXD) TO CHAPEL HILL, NC (IGX), I FIRST BECAME AWARE OF A GLITCH IN THE ALTIMETER READINGS WHEN I OBSERVED INTERMITTENTLY DURING THE CLB THAT THERE WAS AN OCCASIONAL 'SKIP' IN THE VERT SPD INDICATOR. IT SEEMED TO CORRECT AS I LEVELED AT 15000 FT, THE ASSIGNED CRUISE ALT. YET, OUT OF CONCERN ABOUT THE ALTIMETER, APCHING A LEVEL OF IMC WHICH WAS SLIGHTLY HIGHER THAN MY CRUISE ALT AND, WITH A FORECAST OF VFR WX AHEAD AND VISUAL CUES THAT IT WAS IMPROVING, I ASKED FOR A BLOCK TO CLB TO 16000 FT TO KEEP ME IN VFR CONDITIONS OVER THE CLOUD LEVEL.

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.