Narrative:

First officer and myself experienced what we believe was a near miss with an unk aircraft while level at an assigned cruise altitude of FL240. When this incident occurred we were established on J2 approximately 75 NM east of the crestview VOR, after having just descended from FL260. At the moment of occurrence, the first officer and myself heard the unmistakable noise of a passing turboprop aircraft at an extreme close proximity to our aircraft. The first officer at that instant saw a shadow passing from left to right immediately above us. The actual aircraft was not sighted. However, we were both convinced that what passed over us was another aircraft at nearly our altitude. With this in mind we filed a near collision report with the pensacola FAA. The only ATC known aircraft in our vicinity was a military spc, assigned an altitude of 27000'. The FAA is investigating the incident.

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Original NASA ASRS Text

Title: ACR MLG HAS NMAC WITH UNK TURBOPROP ACFT.

Narrative: F/O AND MYSELF EXPERIENCED WHAT WE BELIEVE WAS A NEAR MISS WITH AN UNK ACFT WHILE LEVEL AT AN ASSIGNED CRUISE ALT OF FL240. WHEN THIS INCIDENT OCCURRED WE WERE ESTABLISHED ON J2 APPROX 75 NM E OF THE CRESTVIEW VOR, AFTER HAVING JUST DSNDED FROM FL260. AT THE MOMENT OF OCCURRENCE, THE F/O AND MYSELF HEARD THE UNMISTAKABLE NOISE OF A PASSING TURBOPROP ACFT AT AN EXTREME CLOSE PROX TO OUR ACFT. THE F/O AT THAT INSTANT SAW A SHADOW PASSING FROM LEFT TO RIGHT IMMEDIATELY ABOVE US. THE ACTUAL ACFT WAS NOT SIGHTED. HOWEVER, WE WERE BOTH CONVINCED THAT WHAT PASSED OVER US WAS ANOTHER ACFT AT NEARLY OUR ALT. WITH THIS IN MIND WE FILED A NEAR COLLISION RPT WITH THE PENSACOLA FAA. THE ONLY ATC KNOWN ACFT IN OUR VICINITY WAS A MIL SPC, ASSIGNED AN ALT OF 27000'. THE FAA IS INVESTIGATING THE INCIDENT.

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.