Narrative:

We were performing full stop night takeoff and lndgs on runway 29L. We had requested a third and final landing before returning to the hangar. Our takeoff was on runway 29L and while on downwind we were cleared to land on runway 29R. On left base to runway 29R, we noticed another aircraft to the north and east of us that appeared to be coming south (from over highway 36) and on a path similar to a wide right base for runway 29R. The aircraft was estimated to be approximately 500 ft above us and was thought to be overflying the area, as we had not heard any radio communications between the tower and any aircraft relative to landing while we were in the pattern for this landing. After we had turned final, we attempted to keep this aircraft in view. From the copilot's position, I observed that the aircraft had also turned to a course paralleling the runway and was catching up to us. When the aircraft was directly above us, and just barely visible at the top of our windscreen it was observed to turn on its landing light. At that point we were on approximately a 1/2 mi final and approximately 200 ft AGL. The gap between us rapidly closed to approximately 200 vertical ft. Our evasive action was to turn to a more northwest heading. We then paralleled runway 29R on the north side. We were later cleared by the tower to make left traffic and we made an uneventful landing on runway 29R. The tower noticed both aircraft were on final for runway 29R after the other aircraft had turned on its landing light. Their comment about this observation indicated to us that they were just as surprised as we were. The other aircraft did not acknowledge the tower's call, but when we were well clear we notified the tower that we had deviated to the northwest as our evasive action. While we were conducting our third landing, we did not at any time hear any communications between the tower and any other aircraft relative to 'permission to land.' at approximately XA45 local, the pilot contacted the jeffco control tower by telephone. He attempted to discuss the situation with them. The tower personnel chose not to provide him with any significant details at that time.

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Original NASA ASRS Text

Title: INSTRUCTOR PLT IN AN MO20 ON SHORT FINAL FOR RWY 29R SAW AN UNKNOWN ACFT PASS OVER THE TOP OF HIM AND LAND. THE MO20 TOOK EVASIVE ACTION TO MISS THE UNKNOWN ACFT AND DID NOT HEAR ANY RADIO COM BTWN THE TWR AND THE UNKNOWN ACFT. ATCT LCL CTLR SEEMED SURPRISED AT THE POS OF THE UNKNOWN ACFT AND LATER DID NOT WANT TO DISCUSS THE SIT WITH THE RPTR.

Narrative: WE WERE PERFORMING FULL STOP NIGHT TKOF AND LNDGS ON RWY 29L. WE HAD REQUESTED A THIRD AND FINAL LNDG BEFORE RETURNING TO THE HANGAR. OUR TKOF WAS ON RWY 29L AND WHILE ON DOWNWIND WE WERE CLRED TO LAND ON RWY 29R. ON L BASE TO RWY 29R, WE NOTICED ANOTHER ACFT TO THE N AND E OF US THAT APPEARED TO BE COMING S (FROM OVER HWY 36) AND ON A PATH SIMILAR TO A WIDE R BASE FOR RWY 29R. THE ACFT WAS ESTIMATED TO BE APPROX 500 FT ABOVE US AND WAS THOUGHT TO BE OVERFLYING THE AREA, AS WE HAD NOT HEARD ANY RADIO COMS BTWN THE TWR AND ANY ACFT RELATIVE TO LNDG WHILE WE WERE IN THE PATTERN FOR THIS LNDG. AFTER WE HAD TURNED FINAL, WE ATTEMPTED TO KEEP THIS ACFT IN VIEW. FROM THE COPLT'S POS, I OBSERVED THAT THE ACFT HAD ALSO TURNED TO A COURSE PARALLELING THE RWY AND WAS CATCHING UP TO US. WHEN THE ACFT WAS DIRECTLY ABOVE US, AND JUST BARELY VISIBLE AT THE TOP OF OUR WINDSCREEN IT WAS OBSERVED TO TURN ON ITS LNDG LIGHT. AT THAT POINT WE WERE ON APPROX A 1/2 MI FINAL AND APPROX 200 FT AGL. THE GAP BTWN US RAPIDLY CLOSED TO APPROX 200 VERT FT. OUR EVASIVE ACTION WAS TO TURN TO A MORE NW HDG. WE THEN PARALLELED RWY 29R ON THE N SIDE. WE WERE LATER CLRED BY THE TWR TO MAKE L TFC AND WE MADE AN UNEVENTFUL LNDG ON RWY 29R. THE TWR NOTICED BOTH ACFT WERE ON FINAL FOR RWY 29R AFTER THE OTHER ACFT HAD TURNED ON ITS LNDG LIGHT. THEIR COMMENT ABOUT THIS OBSERVATION INDICATED TO US THAT THEY WERE JUST AS SURPRISED AS WE WERE. THE OTHER ACFT DID NOT ACKNOWLEDGE THE TWR'S CALL, BUT WHEN WE WERE WELL CLR WE NOTIFIED THE TWR THAT WE HAD DEVIATED TO THE NW AS OUR EVASIVE ACTION. WHILE WE WERE CONDUCTING OUR THIRD LNDG, WE DID NOT AT ANY TIME HEAR ANY COMS BTWN THE TWR AND ANY OTHER ACFT RELATIVE TO 'PERMISSION TO LAND.' AT APPROX XA45 LCL, THE PLT CONTACTED THE JEFFCO CTL TWR BY TELEPHONE. HE ATTEMPTED TO DISCUSS THE SIT WITH THEM. THE TWR PERSONNEL CHOSE NOT TO PROVIDE HIM WITH ANY SIGNIFICANT DETAILS AT THAT TIME.

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.