Narrative:

A proving flight was being conducted to add an small transport to a part 135 air carrier certificate. Crew plus 3 FAA personnel were on board. After departing roswell, NM, one FAA personnel (avionics inspector) stated that the #2 engine oil temperature gauge would occasionally fluctuate +/-5 psi. I informed him maintenance had advised me this was normal on the small transport because of the tape display and large scale. I was then informed that he, the inspector, considered any fluctuation rendered the instrument inoperable and therefore, the aircraft should not have been dispatched or flown. He did not inform me of this until after landing apa.

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Original NASA ASRS Text

Title: FLT CREW IS CRITICIZED FOR ACCEPTING DISPATCH OF ACFT WITH MINOR TRANSIENT GAUGE FLUCTUATION BY ONBOARD FAA INSPECTOR.

Narrative: A PROVING FLT WAS BEING CONDUCTED TO ADD AN SMT TO A PART 135 AIR CARRIER CERTIFICATE. CREW PLUS 3 FAA PERSONNEL WERE ON BOARD. AFTER DEPARTING ROSWELL, NM, ONE FAA PERSONNEL (AVIONICS INSPECTOR) STATED THAT THE #2 ENGINE OIL TEMP GAUGE WOULD OCCASIONALLY FLUCTUATE +/-5 PSI. I INFORMED HIM MAINT HAD ADVISED ME THIS WAS NORMAL ON THE SMT BECAUSE OF THE TAPE DISPLAY AND LARGE SCALE. I WAS THEN INFORMED THAT HE, THE INSPECTOR, CONSIDERED ANY FLUCTUATION RENDERED THE INSTRUMENT INOPERABLE AND THEREFORE, THE ACFT SHOULD NOT HAVE BEEN DISPATCHED OR FLOWN. HE DID NOT INFORM ME OF THIS UNTIL AFTER LNDG APA.

Data retrieved from NASA's ASRS site as of August 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.