Narrative:

We were under the control of ict approach descending for landing on runway 1L at ict. After breaking out of a broken cloud layer at 5000' MSL, we leveled at 4000' about 6 mi west of ict and told the controller we had the airport in sight. He said we would be following an air carrier Y who was on a 10 mi final. He gave us 2 more vectors to the 01L ILS when we reported the air carrier Y in sight as we were on the base leg and he cleared us for the visibility approach and to contact the tower. We started our descent from 4000' and as I was checking in with the tower, a single engine small aircraft passed under our nose as we were descending through 3700'. I asked the tower about him and he said he was an small aircraft at 3200' who he wasn't talking to. We continued in for a normal landing. After landing I called the tower to discuss the incident. The approach controller said he had the small aircraft on radar at 2800' and since we were at 4000' and he saw no potential conflict he did not point him out to us. He also said they were only required to maintain 500' sep between VFR and IFR traffic. The tower operator said he had him on radar at 3200' and thought there was no conflict. I can only conclude that some unexpected maneuvering by the small aircraft brought him through our flight path. I feel this situation could have been avoided if we had just been informed of the small aircraft's presence. As far as I remember the only 2 aircraft on approach control frequency was air carrier Y and ourselves. Although the controller said that a trnee was working the radar under supervision. Had we been advised of his presence, with the good visibility present, I'm sure we would have picked him up and avoided this incident.

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Original NASA ASRS Text

Title: CLOSE PROX ACR-MLG GA-SMA IN ICT ARSA.

Narrative: WE WERE UNDER THE CTL OF ICT APCH DSNDING FOR LNDG ON RWY 1L AT ICT. AFTER BREAKING OUT OF A BROKEN CLOUD LAYER AT 5000' MSL, WE LEVELED AT 4000' ABOUT 6 MI W OF ICT AND TOLD THE CTLR WE HAD THE ARPT IN SIGHT. HE SAID WE WOULD BE FOLLOWING AN ACR Y WHO WAS ON A 10 MI FINAL. HE GAVE US 2 MORE VECTORS TO THE 01L ILS WHEN WE RPTED THE ACR Y IN SIGHT AS WE WERE ON THE BASE LEG AND HE CLRED US FOR THE VIS APCH AND TO CONTACT THE TWR. WE STARTED OUR DSNT FROM 4000' AND AS I WAS CHKING IN WITH THE TWR, A SINGLE ENG SMA PASSED UNDER OUR NOSE AS WE WERE DSNDING THROUGH 3700'. I ASKED THE TWR ABOUT HIM AND HE SAID HE WAS AN SMA AT 3200' WHO HE WASN'T TALKING TO. WE CONTINUED IN FOR A NORMAL LNDG. AFTER LNDG I CALLED THE TWR TO DISCUSS THE INCIDENT. THE APCH CTLR SAID HE HAD THE SMA ON RADAR AT 2800' AND SINCE WE WERE AT 4000' AND HE SAW NO POTENTIAL CONFLICT HE DID NOT POINT HIM OUT TO US. HE ALSO SAID THEY WERE ONLY REQUIRED TO MAINTAIN 500' SEP BTWN VFR AND IFR TFC. THE TWR OPERATOR SAID HE HAD HIM ON RADAR AT 3200' AND THOUGHT THERE WAS NO CONFLICT. I CAN ONLY CONCLUDE THAT SOME UNEXPECTED MANEUVERING BY THE SMA BROUGHT HIM THROUGH OUR FLT PATH. I FEEL THIS SITUATION COULD HAVE BEEN AVOIDED IF WE HAD JUST BEEN INFORMED OF THE SMA'S PRESENCE. AS FAR AS I REMEMBER THE ONLY 2 ACFT ON APCH CTL FREQ WAS ACR Y AND OURSELVES. ALTHOUGH THE CTLR SAID THAT A TRNEE WAS WORKING THE RADAR UNDER SUPERVISION. HAD WE BEEN ADVISED OF HIS PRESENCE, WITH THE GOOD VISIBILITY PRESENT, I'M SURE WE WOULD HAVE PICKED HIM UP AND AVOIDED THIS INCIDENT.

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.