Narrative:

I was working R-73, psb hi sector in ZNY, a military fgt departed nxx requesting climb to block altitude FL350 B370 for a flight test, and then a return clearance to nxx. He received his climb on a vector and at approximately mip, he reported termination of test and return clearance request. He was issued an initial heading and descent, and appeared to be complying (we were having difficulty updating mode C) when his transmissions became unreadable. He continued on his heading well past the originally intended point, and then appeared to turn towards etx to the northeast. (His expected clearance was via etx, ard, nxx). He descended through his assigned altitude (his mode C was intermittent, showing about every min or 2). As he made his turn, his transponder cut out completely and he was primary target only. It appeared he would continue to descend (contrary to far's) and air carrier, (a ptw department, medium large transport) at 170 degree was in conflict with fgt projected track, so I turned medium large transport to a 180 degree heading, taking my best guess as to where to get out of fgt's way. I continually issued traffic and finally medium large transport called traffic in sight passing underneath apparently at 165 degree, 'and he took my heart with him', the pilot said. I understand that now this same fgt flight made a strangely similar flight two days ago. He must be stopped, he is risking lives. I don't believe military pilots appreciate the seriousness of their actions and also are unfamiliar with regulations regarding radio failures. In addition, military radios are infamous for appalling quality and a high rate of failures.

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Original NASA ASRS Text

Title: ARTCC CTLR VECTORS MIL FIGHTER WHICH HAS RADIO PROBLEMS AND INTERMITTENT TRANSPONDER. CTLR VECTORS MLG TO AVOID, BUT FGT DOES NOT MAINTAIN ASSIGNED ALT. NMAC.

Narrative: I WAS WORKING R-73, PSB HI SECTOR IN ZNY, A MIL FGT DEPARTED NXX REQUESTING CLB TO BLOCK ALT FL350 B370 FOR A FLT TEST, AND THEN A RETURN CLRNC TO NXX. HE RECEIVED HIS CLB ON A VECTOR AND AT APPROX MIP, HE RPTED TERMINATION OF TEST AND RETURN CLRNC REQUEST. HE WAS ISSUED AN INITIAL HDG AND DSCNT, AND APPEARED TO BE COMPLYING (WE WERE HAVING DIFFICULTY UPDATING MODE C) WHEN HIS TRANSMISSIONS BECAME UNREADABLE. HE CONTINUED ON HIS HDG WELL PAST THE ORIGINALLY INTENDED POINT, AND THEN APPEARED TO TURN TOWARDS ETX TO THE NE. (HIS EXPECTED CLRNC WAS VIA ETX, ARD, NXX). HE DSNDED THROUGH HIS ASSIGNED ALT (HIS MODE C WAS INTERMITTENT, SHOWING ABOUT EVERY MIN OR 2). AS HE MADE HIS TURN, HIS TRANSPONDER CUT OUT COMPLETELY AND HE WAS PRIMARY TARGET ONLY. IT APPEARED HE WOULD CONTINUE TO DSND (CONTRARY TO FAR'S) AND ACR, (A PTW DEPT, MLG) AT 170 DEG WAS IN CONFLICT WITH FGT PROJECTED TRACK, SO I TURNED MLG TO A 180 DEG HDG, TAKING MY BEST GUESS AS TO WHERE TO GET OUT OF FGT'S WAY. I CONTINUALLY ISSUED TFC AND FINALLY MLG CALLED TFC IN SIGHT PASSING UNDERNEATH APPARENTLY AT 165 DEG, 'AND HE TOOK MY HEART WITH HIM', THE PLT SAID. I UNDERSTAND THAT NOW THIS SAME FGT FLT MADE A STRANGELY SIMILAR FLT TWO DAYS AGO. HE MUST BE STOPPED, HE IS RISKING LIVES. I DON'T BELIEVE MIL PLTS APPRECIATE THE SERIOUSNESS OF THEIR ACTIONS AND ALSO ARE UNFAMILIAR WITH REGS REGARDING RADIO FAILURES. IN ADDITION, MIL RADIOS ARE INFAMOUS FOR APPALLING QUALITY AND A HIGH RATE OF FAILURES.

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.