Narrative:

Air carrier X climb out, departing azo during a frequency change from ZAU to ZAU. A white and green small transport Y passed (near miss) west to east and was not observed by ATC controller (frequency 127.55), although immediately after the frequency change (to 135.9, also ZAU) that controller did show an aircraft at VFR 9600' MSL. At the time of the near miss, our aircraft was climbing through 9500' MSL. Bright sunshine and haze prevented sooner detection. Also contributing were checklist associated duties and the frequency change. Ultimately though, if one center controller showed that traffic on his radar, so should the previous one have pointed out traffic to this air crew. Supplemental information from acn 177350: air carrier X was on an IFR flight plan climbing through 9500' talking to departure control on 127.55 when the event occurred. Flight conditions were VFR with bright sunlight and haze. Both crew members were momentarily occupied with departure/climb crew duties. I took a moment to look up from my cockpit duties and saw small transport Y (green and white) very close to our aircraft. I immediately turned the aircraft to the right to avoid small transport Y. There was no warning/traffic call to us from departure control. Supplemental information from acn 176630: on initial call I climbed air carrier X to 15000'. I went to do some coordination. Went back to air carrier X strip. It showed 17000' coordinated. I called air carrier X and cleared the aircraft to 17000'. Air carrier X asked if I showed a VFR at 9500'. I said no, just over ibs and 10 mi to the left. Air carrier X said he was filing a near miss. 2 updates later a VFR target showed at 9500'.

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Original NASA ASRS Text

Title: ACR X HAD NMAC WITH SMT Y. EVASIVE ACTION TAKEN. SEE AND AVOID CONCEPT.

Narrative: ACR X CLBOUT, DEPARTING AZO DURING A FREQ CHANGE FROM ZAU TO ZAU. A WHITE AND GREEN SMT Y PASSED (NEAR MISS) W TO E AND WAS NOT OBSERVED BY ATC CTLR (FREQ 127.55), ALTHOUGH IMMEDIATELY AFTER THE FREQ CHANGE (TO 135.9, ALSO ZAU) THAT CTLR DID SHOW AN ACFT AT VFR 9600' MSL. AT THE TIME OF THE NEAR MISS, OUR ACFT WAS CLBING THROUGH 9500' MSL. BRIGHT SUNSHINE AND HAZE PREVENTED SOONER DETECTION. ALSO CONTRIBUTING WERE CHKLIST ASSOCIATED DUTIES AND THE FREQ CHANGE. ULTIMATELY THOUGH, IF ONE CENTER CTLR SHOWED THAT TFC ON HIS RADAR, SO SHOULD THE PREVIOUS ONE HAVE POINTED OUT TFC TO THIS AIR CREW. SUPPLEMENTAL INFO FROM ACN 177350: ACR X WAS ON AN IFR FLT PLAN CLBING THROUGH 9500' TALKING TO DEP CTL ON 127.55 WHEN THE EVENT OCCURRED. FLT CONDITIONS WERE VFR WITH BRIGHT SUNLIGHT AND HAZE. BOTH CREW MEMBERS WERE MOMENTARILY OCCUPIED WITH DEP/CLB CREW DUTIES. I TOOK A MOMENT TO LOOK UP FROM MY COCKPIT DUTIES AND SAW SMT Y (GREEN AND WHITE) VERY CLOSE TO OUR ACFT. I IMMEDIATELY TURNED THE ACFT TO THE RIGHT TO AVOID SMT Y. THERE WAS NO WARNING/TFC CALL TO US FROM DEP CTL. SUPPLEMENTAL INFO FROM ACN 176630: ON INITIAL CALL I CLBED ACR X TO 15000'. I WENT TO DO SOME COORD. WENT BACK TO ACR X STRIP. IT SHOWED 17000' COORDINATED. I CALLED ACR X AND CLRED THE ACFT TO 17000'. ACR X ASKED IF I SHOWED A VFR AT 9500'. I SAID NO, JUST OVER IBS AND 10 MI TO THE LEFT. ACR X SAID HE WAS FILING A NEAR MISS. 2 UPDATES LATER A VFR TARGET SHOWED AT 9500'.

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.