Narrative:

En route from fdk to lwm, aircraft flew into unseen cloud cover. Immediately descended to 3500 ft, and remained clear of clouds thereafter. Ideally, the flight should have been IFR because part of it was in night darkness. But, flight service was reporting icing in cloud, and aircraft not equipped to de-ice. IFR would have put the aircraft into IMC conditions. Additional factor: there was a SIGMET current for moderate turbulence below 3500 ft.

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Original NASA ASRS Text

Title: UNAUTHORIZED PENETRATION OF AIRSPACE IN SMA'S PROX OF ARSA.

Narrative: ENRTE FROM FDK TO LWM, ACFT FLEW INTO UNSEEN CLOUD COVER. IMMEDIATELY DSNDED TO 3500 FT, AND REMAINED CLR OF CLOUDS THEREAFTER. IDEALLY, THE FLT SHOULD HAVE BEEN IFR BECAUSE PART OF IT WAS IN NIGHT DARKNESS. BUT, FLT SVC WAS RPTING ICING IN CLOUD, AND ACFT NOT EQUIPPED TO DE-ICE. IFR WOULD HAVE PUT THE ACFT INTO IMC CONDITIONS. ADDITIONAL FACTOR: THERE WAS A SIGMET CURRENT FOR MODERATE TURB BELOW 3500 FT.

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.