Narrative:

As we approached cheyenne, on V19 from the south, I was impressed by the fact that approach was keeping us high (10000') for longer than it usually does. (It usually starts us down about 20-25 mi south; we were still at 10000' 10 mi out.) I had already reported the airport in sight, as requested, and approach advised that a commuter was departing runway 3-0 to the west, and would turn southeast. He would have lower for us momentarily. Shortly thereafter, approach cleared us for the visibility, and announced that he had both the commuter and us in sight. The commuter also called out that he had us in sight. Leaving 10000' for 9000, I looked up just in time to see the commuter about to fill the windshield, passing left to right and climbing across our descent path. The crew of the light transport called out a near miss and told the controller that if they hadn't seen us, it would have been a midair. They said that they had gone into a 1500 FPM dive to avoid us. I'm still not sure how they came so close to us, if in fact they had had us in sight, as they had called out. Nor do I understand how, if, as he professed, approach had us in sight, he watched us nearly collide. For my part, I was impressed with how complacent I had become about seeing and avoiding, while on an IFR flight plan in VFR conditions. I'm reminded to be more vigilant, especially in a non radar environment.

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Original NASA ASRS Text

Title: NMAC AT CYS.

Narrative: AS WE APCHED CHEYENNE, ON V19 FROM THE S, I WAS IMPRESSED BY THE FACT THAT APCH WAS KEEPING US HIGH (10000') FOR LONGER THAN IT USUALLY DOES. (IT USUALLY STARTS US DOWN ABOUT 20-25 MI S; WE WERE STILL AT 10000' 10 MI OUT.) I HAD ALREADY RPTED THE ARPT IN SIGHT, AS REQUESTED, AND APCH ADVISED THAT A COMMUTER WAS DEPARTING RWY 3-0 TO THE W, AND WOULD TURN SE. HE WOULD HAVE LOWER FOR US MOMENTARILY. SHORTLY THEREAFTER, APCH CLRED US FOR THE VIS, AND ANNOUNCED THAT HE HAD BOTH THE COMMUTER AND US IN SIGHT. THE COMMUTER ALSO CALLED OUT THAT HE HAD US IN SIGHT. LEAVING 10000' FOR 9000, I LOOKED UP JUST IN TIME TO SEE THE COMMUTER ABOUT TO FILL THE WINDSHIELD, PASSING LEFT TO RIGHT AND CLBING ACROSS OUR DSNT PATH. THE CREW OF THE LTT CALLED OUT A NEAR MISS AND TOLD THE CTLR THAT IF THEY HADN'T SEEN US, IT WOULD HAVE BEEN A MIDAIR. THEY SAID THAT THEY HAD GONE INTO A 1500 FPM DIVE TO AVOID US. I'M STILL NOT SURE HOW THEY CAME SO CLOSE TO US, IF IN FACT THEY HAD HAD US IN SIGHT, AS THEY HAD CALLED OUT. NOR DO I UNDERSTAND HOW, IF, AS HE PROFESSED, APCH HAD US IN SIGHT, HE WATCHED US NEARLY COLLIDE. FOR MY PART, I WAS IMPRESSED WITH HOW COMPLACENT I HAD BECOME ABOUT SEEING AND AVOIDING, WHILE ON AN IFR FLT PLAN IN VFR CONDITIONS. I'M REMINDED TO BE MORE VIGILANT, ESPECIALLY IN A NON RADAR ENVIRONMENT.

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.