Narrative:

On feb/mon/97, 2 company commuter airplanes nearly collided in midair over fresno, ca. At approximately 4000 ft and 5 mi from the airport, approach control asked if we could accept a visual approach and keep the base leg within 2 mi of the airport. I acknowledged that we could, and we proceeded as cleared (right traffic for runway 29R). As we began a turn for the base leg, the tower controller advised us of traffic, 2 F16 military aircraft and a company jetstream. We were then instructed to continue downwind. The captain wanted to clarify the instructions so I asked the controller to verify that he would call our base turn. Shortly thereafter, the tower controller called our base and switched our runway to runway 29L, advising that company was 2 mi out for runway 29R. He then changed our instructions to fly directly to the airport and gave our company traffic instructions to make a 360 degree turn. At that time we got a TA from TCASII. The traffic was at our altitude and very close. We did not see the traffic until it was no longer a factor. After landing we discussed the incident with the other crew. They did see us, however, at very close range. We agreed that contributing factors were the haze that existed at the time. ATC controling multiple frequencys, and conflicting instructions. The bottom line is that we, as pilots, are responsible to see and avoid.

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Original NASA ASRS Text

Title: NMAC BTWN 2 COMPANY BRITISH AEROSPACE JETSTREAM 32'S TURNING BASE LEG. THE OTHER COMPANY ACFT CREW DID OBSERVE THE RPTR WHEN THEY WERE GIVEN A TURN BY ATC.

Narrative: ON FEB/MON/97, 2 COMPANY COMMUTER AIRPLANES NEARLY COLLIDED IN MIDAIR OVER FRESNO, CA. AT APPROX 4000 FT AND 5 MI FROM THE ARPT, APCH CTL ASKED IF WE COULD ACCEPT A VISUAL APCH AND KEEP THE BASE LEG WITHIN 2 MI OF THE ARPT. I ACKNOWLEDGED THAT WE COULD, AND WE PROCEEDED AS CLRED (R TFC FOR RWY 29R). AS WE BEGAN A TURN FOR THE BASE LEG, THE TWR CTLR ADVISED US OF TFC, 2 F16 MIL ACFT AND A COMPANY JETSTREAM. WE WERE THEN INSTRUCTED TO CONTINUE DOWNWIND. THE CAPT WANTED TO CLARIFY THE INSTRUCTIONS SO I ASKED THE CTLR TO VERIFY THAT HE WOULD CALL OUR BASE TURN. SHORTLY THEREAFTER, THE TWR CTLR CALLED OUR BASE AND SWITCHED OUR RWY TO RWY 29L, ADVISING THAT COMPANY WAS 2 MI OUT FOR RWY 29R. HE THEN CHANGED OUR INSTRUCTIONS TO FLY DIRECTLY TO THE ARPT AND GAVE OUR COMPANY TFC INSTRUCTIONS TO MAKE A 360 DEG TURN. AT THAT TIME WE GOT A TA FROM TCASII. THE TFC WAS AT OUR ALT AND VERY CLOSE. WE DID NOT SEE THE TFC UNTIL IT WAS NO LONGER A FACTOR. AFTER LNDG WE DISCUSSED THE INCIDENT WITH THE OTHER CREW. THEY DID SEE US, HOWEVER, AT VERY CLOSE RANGE. WE AGREED THAT CONTRIBUTING FACTORS WERE THE HAZE THAT EXISTED AT THE TIME. ATC CTLING MULTIPLE FREQS, AND CONFLICTING INSTRUCTIONS. THE BOTTOM LINE IS THAT WE, AS PLTS, ARE RESPONSIBLE TO SEE AND AVOID.

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.