Narrative:

We were en route from harrisburg, capital city (cxy), to lancaster, PA, (lns), at 3500 ft. Runways in use were 13 and 8. We were in contact with harrisburg departure and requested the ILS 8 approach. We were told by harrisburg departure to descend to 3000 ft and maintain 3000 until established on the localizer, cleared for the ILS 8 approach, and to contact lancaster tower on 120.9 at the OM (manor). I complied and made a left turn, intercepted the localizer an descended to 2600 ft. Upon hearing a somewhat congested tower frequency (the controller was working 2 student pilots north and east of the airport), I contacted the tower a mile west of the marker. I was told to continue the approach inbound and contact them at the OM. I continued inbound and had trouble getting free on the frequency (as previously stated, the frequency was busy). Approximately 4 mi from the airport, I told the tower I was inside the marker, still inbound, and received no reply. The controller was still working numerous aircraft in several sectors. I also heard him clear an small aircraft Y that was somewhere south and west of the airport to land on runway 8. There was no traffic in front of me, so I assumed he was behind me. I flew left of the localizer course. At that point, we saw the small aircraft Y approximately on the localizer course, right and slightly above us with only several hundred ft separation. I contacted the tower and inquired, 'tower, did that small aircraft Y see us?' the reply from the tower was 'no, he did not.' I indicated to the tower that we were too close to each other for comfort and the tower replied 'sorry about that, I guess we lost track of you for a min, we got kinda busy.' at that point, we were told to break off the approach and enter a right base for runway 13. It was a subsequently uneventful landing. That was the chain of events which occurred. Pursuant to the human performance considerations, I think the controller's attention was diverted to the other aircraft and the students and forgot that he had 2 aircraft approaching the same runway at the same time. Unfortunately, 'see and be seen' did not work. The small aircraft Y visibility was obscured down and to the left. And the small aircraft X visibility was obscured up and to the rear. In my opinion, we were very fortunate that the 2 pilots, who were both in the right place at the right time, did not end up colliding in midair.

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Original NASA ASRS Text

Title: NMAC OF 2 SMAS ON FINAL APCH. BOTH CLRED BY TWR.

Narrative: WE WERE ENRTE FROM HARRISBURG, CAPITAL CITY (CXY), TO LANCASTER, PA, (LNS), AT 3500 FT. RWYS IN USE WERE 13 AND 8. WE WERE IN CONTACT WITH HARRISBURG DEP AND REQUESTED THE ILS 8 APCH. WE WERE TOLD BY HARRISBURG DEP TO DSND TO 3000 FT AND MAINTAIN 3000 UNTIL ESTABLISHED ON THE LOC, CLRED FOR THE ILS 8 APCH, AND TO CONTACT LANCASTER TWR ON 120.9 AT THE OM (MANOR). I COMPLIED AND MADE A L TURN, INTERCEPTED THE LOC AN DSNDED TO 2600 FT. UPON HEARING A SOMEWHAT CONGESTED TWR FREQ (THE CTLR WAS WORKING 2 STUDENT PILOTS N AND E OF THE ARPT), I CONTACTED THE TWR A MILE W OF THE MARKER. I WAS TOLD TO CONTINUE THE APCH INBOUND AND CONTACT THEM AT THE OM. I CONTINUED INBOUND AND HAD TROUBLE GETTING FREE ON THE FREQ (AS PREVIOUSLY STATED, THE FREQ WAS BUSY). APPROX 4 MI FROM THE ARPT, I TOLD THE TWR I WAS INSIDE THE MARKER, STILL INBOUND, AND RECEIVED NO REPLY. THE CTLR WAS STILL WORKING NUMEROUS ACFT IN SEVERAL SECTORS. I ALSO HEARD HIM CLR AN SMA Y THAT WAS SOMEWHERE S AND W OF THE ARPT TO LAND ON RWY 8. THERE WAS NO TFC IN FRONT OF ME, SO I ASSUMED HE WAS BEHIND ME. I FLEW L OF THE LOC COURSE. AT THAT POINT, WE SAW THE SMA Y APPROX ON THE LOC COURSE, R AND SLIGHTLY ABOVE US WITH ONLY SEVERAL HUNDRED FT SEPARATION. I CONTACTED THE TWR AND INQUIRED, 'TWR, DID THAT SMA Y SEE US?' THE REPLY FROM THE TWR WAS 'NO, HE DID NOT.' I INDICATED TO THE TWR THAT WE WERE TOO CLOSE TO EACH OTHER FOR COMFORT AND THE TWR REPLIED 'SORRY ABOUT THAT, I GUESS WE LOST TRACK OF YOU FOR A MIN, WE GOT KINDA BUSY.' AT THAT POINT, WE WERE TOLD TO BREAK OFF THE APCH AND ENTER A R BASE FOR RWY 13. IT WAS A SUBSEQUENTLY UNEVENTFUL LNDG. THAT WAS THE CHAIN OF EVENTS WHICH OCCURRED. PURSUANT TO THE HUMAN PERFORMANCE CONSIDERATIONS, I THINK THE CTLR'S ATTN WAS DIVERTED TO THE OTHER ACFT AND THE STUDENTS AND FORGOT THAT HE HAD 2 ACFT APCHING THE SAME RWY AT THE SAME TIME. UNFORTUNATELY, 'SEE AND BE SEEN' DID NOT WORK. THE SMA Y VISIBILITY WAS OBSCURED DOWN AND TO THE L. AND THE SMA X VISIBILITY WAS OBSCURED UP AND TO THE REAR. IN MY OPINION, WE WERE VERY FORTUNATE THAT THE 2 PLTS, WHO WERE BOTH IN THE RIGHT PLACE AT THE RIGHT TIME, DID NOT END UP COLLIDING IN MIDAIR.

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.