Narrative:

I was notified by the first officer of the other aircraft that he believed his captain had maneuvered inappropriately within proximity to our aircraft. They did not have visual reference to us and were referencing their TCAS. We had visual contact with the aircraft from several mi out; observed the maneuver; and witnessed no compromise of vertical separation. We were in cruise at 1000 ft heading sbound. He witnessed the other aircraft heading northbound at 1500 ft; confirmed TCAS; and to our left. The aircraft turned westerly and passed overhead approximately 500 ft. I believe there was no incident and that the concern of the first officer was due to his reference to the TCAS; not to the actual altitudes of the aircraft. The other flight crew also lacked visual reference to my aircraft; which was traveling the proper altitude for the route and on course.

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Original NASA ASRS Text

Title: A DHC-6 CAPTAIN REPORTS PASSING APPROXIMATELY 500 FT BELOW ANOTHER DHC-6; WHICH WAS OF SOME CONCERN TO THE OTHER AIRCRAFT'S FO.

Narrative: I WAS NOTIFIED BY THE FO OF THE OTHER ACFT THAT HE BELIEVED HIS CAPT HAD MANEUVERED INAPPROPRIATELY WITHIN PROX TO OUR ACFT. THEY DID NOT HAVE VISUAL REF TO US AND WERE REFING THEIR TCAS. WE HAD VISUAL CONTACT WITH THE ACFT FROM SEVERAL MI OUT; OBSERVED THE MANEUVER; AND WITNESSED NO COMPROMISE OF VERT SEPARATION. WE WERE IN CRUISE AT 1000 FT HEADING SBOUND. HE WITNESSED THE OTHER ACFT HEADING NBOUND AT 1500 FT; CONFIRMED TCAS; AND TO OUR L. THE ACFT TURNED WESTERLY AND PASSED OVERHEAD APPROX 500 FT. I BELIEVE THERE WAS NO INCIDENT AND THAT THE CONCERN OF THE FO WAS DUE TO HIS REF TO THE TCAS; NOT TO THE ACTUAL ALTS OF THE ACFT. THE OTHER FLT CREW ALSO LACKED VISUAL REF TO MY ACFT; WHICH WAS TRAVELING THE PROPER ALT FOR THE RTE AND ON COURSE.

Data retrieved from NASA's ASRS site as of January 2009 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.