Narrative:

We were climbing to FL330--while climbing thru 27000' when the first officer made an exclamation(!) and grabbed the yoke. I saw light transport Y in his forward windshield. Light transport Y passed below our aircraft and was in a descending left turn as I saw it; light transport Y passed beneath us and I again saw it in my left windows. Immediately after the 'near-miss' we called ny center (132.17) and asked 'what was that' (or something to that effect). Ny center immediately replied, 'widebody transport X we've been trying to call you, there's been a 'stuck' microphone on the frequency.' we did not notice any static or 'carrier-wave on the frequency, and ny center was `clear' as we talked. They (ZNY) also were apologetic and answered immediately on initial call. Callback conversation with reporter revealed following information. Reporter (widebody transport captain) asked to be met at destination for a follow-up near midair collision report. A FSDO inspector met the flight and took the necessary information from the flight crew. Widebody transport flight crew was skeptical about the center's radio report of a 'stuck microphone.' the FSDO inspector agreed to do a follow-up investigation to ascertain exactly what happened. The subsequent investigation revealed that the controller did try numerous times to contact the reporter's aircraft to affect sep but there was a carrier wave on the frequency and contact was not established until after the near collision. Reporter stated that he was extremely grateful that the pilot of the cpr small transport was alert enough to take evasive action that prevented a midair collision.

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Original NASA ASRS Text

Title: BLOCKED FREQ CAUSED LESS THAN STANDARD SEPARATION AND NEAR MIDAIR COLLISION.

Narrative: WE WERE CLBING TO FL330--WHILE CLBING THRU 27000' WHEN THE F/O MADE AN EXCLAMATION(!) AND GRABBED THE YOKE. I SAW LTT Y IN HIS FORWARD WINDSHIELD. LTT Y PASSED BELOW OUR ACFT AND WAS IN A DSNDING L TURN AS I SAW IT; LTT Y PASSED BENEATH US AND I AGAIN SAW IT IN MY L WINDOWS. IMMEDIATELY AFTER THE 'NEAR-MISS' WE CALLED NY CENTER (132.17) AND ASKED 'WHAT WAS THAT' (OR SOMETHING TO THAT EFFECT). NY CENTER IMMEDIATELY REPLIED, 'WDB X WE'VE BEEN TRYING TO CALL YOU, THERE'S BEEN A 'STUCK' MIKE ON THE FREQ.' WE DID NOT NOTICE ANY STATIC OR 'CARRIER-WAVE ON THE FREQ, AND NY CENTER WAS `CLR' AS WE TALKED. THEY (ZNY) ALSO WERE APOLOGETIC AND ANSWERED IMMEDIATELY ON INITIAL CALL. CALLBACK CONVERSATION WITH RPTR REVEALED FOLLOWING INFO. RPTR (WDB CAPT) ASKED TO BE MET AT DEST FOR A FOLLOW-UP NMAC RPT. A FSDO INSPECTOR MET THE FLT AND TOOK THE NECESSARY INFO FROM THE FLT CREW. WDB FLT CREW WAS SKEPTICAL ABOUT THE CENTER'S RADIO RPT OF A 'STUCK MIKE.' THE FSDO INSPECTOR AGREED TO DO A FOLLOW-UP INVESTIGATION TO ASCERTAIN EXACTLY WHAT HAPPENED. THE SUBSEQUENT INVESTIGATION REVEALED THAT THE CTLR DID TRY NUMEROUS TIMES TO CONTACT THE RPTR'S ACFT TO AFFECT SEP BUT THERE WAS A CARRIER WAVE ON THE FREQ AND CONTACT WAS NOT ESTABLISHED UNTIL AFTER THE NEAR COLLISION. RPTR STATED THAT HE WAS EXTREMELY GRATEFUL THAT THE PLT OF THE CPR SMT WAS ALERT ENOUGH TO TAKE EVASIVE ACTION THAT PREVENTED A MIDAIR COLLISION.

Data retrieved from NASA's ASRS site as of August 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.