Narrative:

At 13700' MSL in the climb, my copilot saw an light transport at 10 O'clock approximately 1/4 NM crossing left to right. He called out the traffic and I observed the light transport at 12 O'clock. I estimated the light transport to be less than 500' above our altitude. Horizontal sep was estimated to be 500' or less. Our heading was approximately 332 degrees as we were tracking the bsy 332 degree right. His heading was approximately 100 degrees. ATC told us the light transport had been given a vector away from us, but that he cancelled his IFR clearance in response to center's vector. The controller got busy with other traffic and never called the light transport out to us. The controller admitted fault by not calling out the light transport again when he cancelled his IFR, but he had other duties. The light transport never called us in sight to ATC. Flight conditions were VMC, no ceiling. Far's state that we will only be given sep from other IFR traffic. The light transport was no longer under IFR at the time of the incident. Although the controller admitted error, my complaint is more against a regulation that allows the light transport to cancel his IFR and subvert the intentions of the controller to provide traffic sep. I fault the light transport pilot, not the controller. Supplemental information from acn 101438: the light transport was heading west to east in a descent at a high rate of speed. By the time I noticed him in our 10 O'clock position and less than 1/4 mi, and by the time I started to think about turning the aircraft, he was in our 12 O'clock position moving from the left to right at our altitude, and only 500' off the nose. I could plainly read all markings on the aircraft.

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Original NASA ASRS Text

Title: ACR-LGT HAS NMAC WITH CPR-LTT DESCENDING VFR.

Narrative: AT 13700' MSL IN THE CLB, MY COPLT SAW AN LTT AT 10 O'CLOCK APPROX 1/4 NM XING LEFT TO RIGHT. HE CALLED OUT THE TFC AND I OBSERVED THE LTT AT 12 O'CLOCK. I ESTIMATED THE LTT TO BE LESS THAN 500' ABOVE OUR ALT. HORIZ SEP WAS ESTIMATED TO BE 500' OR LESS. OUR HDG WAS APPROX 332 DEGS AS WE WERE TRACKING THE BSY 332 DEG R. HIS HDG WAS APPROX 100 DEGS. ATC TOLD US THE LTT HAD BEEN GIVEN A VECTOR AWAY FROM US, BUT THAT HE CANCELLED HIS IFR CLRNC IN RESPONSE TO CENTER'S VECTOR. THE CTLR GOT BUSY WITH OTHER TFC AND NEVER CALLED THE LTT OUT TO US. THE CTLR ADMITTED FAULT BY NOT CALLING OUT THE LTT AGAIN WHEN HE CANCELLED HIS IFR, BUT HE HAD OTHER DUTIES. THE LTT NEVER CALLED US IN SIGHT TO ATC. FLT CONDITIONS WERE VMC, NO CEILING. FAR'S STATE THAT WE WILL ONLY BE GIVEN SEP FROM OTHER IFR TFC. THE LTT WAS NO LONGER UNDER IFR AT THE TIME OF THE INCIDENT. ALTHOUGH THE CTLR ADMITTED ERROR, MY COMPLAINT IS MORE AGAINST A REG THAT ALLOWS THE LTT TO CANCEL HIS IFR AND SUBVERT THE INTENTIONS OF THE CTLR TO PROVIDE TFC SEP. I FAULT THE LTT PLT, NOT THE CTLR. SUPPLEMENTAL INFO FROM ACN 101438: THE LTT WAS HDG W TO E IN A DSCNT AT A HIGH RATE OF SPD. BY THE TIME I NOTICED HIM IN OUR 10 O'CLOCK POS AND LESS THAN 1/4 MI, AND BY THE TIME I STARTED TO THINK ABOUT TURNING THE ACFT, HE WAS IN OUR 12 O'CLOCK POS MOVING FROM THE LEFT TO RIGHT AT OUR ALT, AND ONLY 500' OFF THE NOSE. I COULD PLAINLY READ ALL MARKINGS ON THE ACFT.

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.