Narrative:

Radar controller accepted handoff on 2 military fgt's landing at bkf. We had 10 aircraft in the sector. We were metering den arrs with den VOR OTS. The fgt's radios were extremely intermittent. Radar controller instructed fgt's to turn right heading 120. They didn't respond. Radar controller waited a while then instructed fgt's to turn right heading 120. Aircraft finally acknowledged turn. Radar controller then told fgt's to expedite descent from FL240 to 16,000 diving them right thru air carrier X at 17,000'. Fgt's then became NORDO again. Radar controller could have left the fgt's at FL240 and we all would have been safe or dumped air carrier X to 15,000' and we would have had vertical separation. Problem arose because of poor radios in military fgt's discovered by observation and oedp. Contributing factors: poor radar controller performance. Corrective actions: fix radios in fighters and center's poor decision by radar controller to descend 2 fgt's. Lack of action by radar controller to positively control situation. Supplemental information from acn 125588: air carrier X was holding at 17,000' southwest of denver and just been given a vector to den of 020. 2 military fgt's northwest of our position (headed for buckley angb) were told to maintain FL180. They descended to 16,000' thru our flight path, passing from our 10-4 O'clock position under with west/I 300' +/- headed southeast. ATC called them several times. We were unable to hear their response because of the UHF frequency. It looked like they were in a dive to keep from getting closer than they were. Talking to ATC later they (fgt pilots) said they had us in sight. The fgt pilots should have turned/climbed.

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Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION BETWEEN ACR X AND 2 MIL FGT'S. SYSTEM ERROR.

Narrative: RADAR CTLR ACCEPTED HANDOFF ON 2 MIL FGT'S LNDG AT BKF. WE HAD 10 ACFT IN THE SECTOR. WE WERE METERING DEN ARRS WITH DEN VOR OTS. THE FGT'S RADIOS WERE EXTREMELY INTERMITTENT. RADAR CTLR INSTRUCTED FGT'S TO TURN RIGHT HDG 120. THEY DIDN'T RESPOND. RADAR CTLR WAITED A WHILE THEN INSTRUCTED FGT'S TO TURN RIGHT HDG 120. ACFT FINALLY ACKNOWLEDGED TURN. RADAR CTLR THEN TOLD FGT'S TO EXPEDITE DSCNT FROM FL240 TO 16,000 DIVING THEM RIGHT THRU ACR X AT 17,000'. FGT'S THEN BECAME NORDO AGAIN. RADAR CTLR COULD HAVE LEFT THE FGT'S AT FL240 AND WE ALL WOULD HAVE BEEN SAFE OR DUMPED ACR X TO 15,000' AND WE WOULD HAVE HAD VERTICAL SEPARATION. PROBLEM AROSE BECAUSE OF POOR RADIOS IN MIL FGT'S DISCOVERED BY OBSERVATION AND OEDP. CONTRIBUTING FACTORS: POOR RADAR CTLR PERFORMANCE. CORRECTIVE ACTIONS: FIX RADIOS IN FIGHTERS AND CENTER'S POOR DECISION BY RADAR CTLR TO DSND 2 FGT'S. LACK OF ACTION BY RADAR CTLR TO POSITIVELY CTL SITUATION. SUPPLEMENTAL INFORMATION FROM ACN 125588: ACR X WAS HOLDING AT 17,000' SW OF DENVER AND JUST BEEN GIVEN A VECTOR TO DEN OF 020. 2 MIL FGT'S NW OF OUR POSITION (HEADED FOR BUCKLEY ANGB) WERE TOLD TO MAINTAIN FL180. THEY DESCENDED TO 16,000' THRU OUR FLT PATH, PASSING FROM OUR 10-4 O'CLOCK POSITION UNDER WITH W/I 300' +/- HEADED SE. ATC CALLED THEM SEVERAL TIMES. WE WERE UNABLE TO HEAR THEIR RESPONSE BECAUSE OF THE UHF FREQ. IT LOOKED LIKE THEY WERE IN A DIVE TO KEEP FROM GETTING CLOSER THAN THEY WERE. TALKING TO ATC LATER THEY (FGT PLTS) SAID THEY HAD US IN SIGHT. THE FGT PLTS SHOULD HAVE TURNED/CLIMBED.

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.