Narrative:

On mar/mon/98, while operating as flight X, I encountered an area of reduced visibility that required a standard rate 180 degree turn to exit. The WX conditions at the time consisted of an indefinite ceiling and flight visibility of 2-3 mi, in fog. The tundra, being snow covered, combined with a low ceiling made it difficult to identify the area of dense fog that was encountered. Once the visibility began to decrease, I initiated a standard rate, 180 degree turn and immediately regained 2-3 mi of flight visibility. I cannot say for certain what the visibility was reduced to, due to the fact I began flying solely by reference to instruments. However, it is likely that the visibility was reduced to less than 1 mi, if not zero.

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Original NASA ASRS Text

Title: PLT OF A C207 INADVERTENTLY FLEW INTO A FOG BANK OVER ALASKAN TUNDRA ENRTE TO NEARBY ARPT AND IMMEDIATELY MADE A 180 DEG TURN BACK IN VFR CONDITIONS.

Narrative: ON MAR/MON/98, WHILE OPERATING AS FLT X, I ENCOUNTERED AN AREA OF REDUCED VISIBILITY THAT REQUIRED A STANDARD RATE 180 DEG TURN TO EXIT. THE WX CONDITIONS AT THE TIME CONSISTED OF AN INDEFINITE CEILING AND FLT VISIBILITY OF 2-3 MI, IN FOG. THE TUNDRA, BEING SNOW COVERED, COMBINED WITH A LOW CEILING MADE IT DIFFICULT TO IDENT THE AREA OF DENSE FOG THAT WAS ENCOUNTERED. ONCE THE VISIBILITY BEGAN TO DECREASE, I INITIATED A STANDARD RATE, 180 DEG TURN AND IMMEDIATELY REGAINED 2-3 MI OF FLT VISIBILITY. I CANNOT SAY FOR CERTAIN WHAT THE VISIBILITY WAS REDUCED TO, DUE TO THE FACT I BEGAN FLYING SOLELY BY REF TO INSTS. HOWEVER, IT IS LIKELY THAT THE VISIBILITY WAS REDUCED TO LESS THAN 1 MI, IF NOT ZERO.

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.