Narrative:

Aircraft #1 cruising east at 3500 ft VFR with departure advisories. VFR aircraft #2 cruising west at wrong VFR altitude (3500 ft). Departure radar did not call traffic, haze a factor in not spotting traffic sooner. To avoid collision, had to bank hard left and decrease power. Aircraft #2 was traveling from my left to right and approaching. Kansas city departure confirmed primary target was cruising at wrong altitude for direction of travel. This event occurred under class B airspace along a departure corridor. ATC workload was moderate. ATC should have called traffic, which it later admitted it had as a primary return. Aircraft #2 should have been at the right cruising altitude -- especially taking into account the nature of the congested or busy airspace in close proximity to the mci class B airspace. My scan could have been better and perhaps I could have spotted the traffic sooner.

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Original NASA ASRS Text

Title: A C206 PLT IN CRUISE AT 3500 FT IN CLASS B AIRSPACE, TOOK EVASIVE ACTION TO AVOID ANOTHER ACFT AT THE SAME ALT.

Narrative: ACFT #1 CRUISING E AT 3500 FT VFR WITH DEP ADVISORIES. VFR ACFT #2 CRUISING W AT WRONG VFR ALT (3500 FT). DEP RADAR DID NOT CALL TFC, HAZE A FACTOR IN NOT SPOTTING TFC SOONER. TO AVOID COLLISION, HAD TO BANK HARD L AND DECREASE PWR. ACFT #2 WAS TRAVELING FROM MY L TO R AND APCHING. KANSAS CITY DEP CONFIRMED PRIMARY TARGET WAS CRUISING AT WRONG ALT FOR DIRECTION OF TRAVEL. THIS EVENT OCCURRED UNDER CLASS B AIRSPACE ALONG A DEP CORRIDOR. ATC WORKLOAD WAS MODERATE. ATC SHOULD HAVE CALLED TFC, WHICH IT LATER ADMITTED IT HAD AS A PRIMARY RETURN. ACFT #2 SHOULD HAVE BEEN AT THE RIGHT CRUISING ALT -- ESPECIALLY TAKING INTO ACCOUNT THE NATURE OF THE CONGESTED OR BUSY AIRSPACE IN CLOSE PROX TO THE MCI CLASS B AIRSPACE. MY SCAN COULD HAVE BEEN BETTER AND PERHAPS I COULD HAVE SPOTTED THE TFC SOONER.

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.