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ATC equipment problem radio wrong aircraft air carrier X descent through occupied altitude had less than standard separation from mlt. System error.
| Attributes | |
| ACN | 242486 |
| Time | |
| Date | 199305 |
| Day | Mon |
| Local Time Of Day | 1201 To 1800 |
| Place | |
| Locale Reference | atc facility : ith |
| State Reference | NY |
| Altitude | msl bound lower : 22000 msl bound upper : 23000 |
| Environment | |
| Flight Conditions | IMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | artcc : zbw tracon : dfw |
| Operator | common carrier : air carrier |
| Make Model Name | Any Unknown or Unlisted Aircraft Manufacturer |
| Flight Phase | descent other |
| Flight Plan | IFR |
| Aircraft 2 | |
| Operator | other |
| Make Model Name | Small Transport, Low Wing, 2 Turboprop Eng |
| Flight Phase | cruise other |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | government : faa |
| Function | controller : radar |
| Qualification | controller : radar |
| Experience | controller radar : 30 |
| ASRS Report | 242486 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Events | |
| Anomaly | conflict : airborne less severe non adherence : published procedure non adherence : required legal separation |
| Independent Detector | other controllera |
| Resolutory Action | controller : issued new clearance other |
| Consequence | faa : investigated |
| Miss Distance | horizontal : 24600 vertical : 300 |
| Supplementary | |
| Primary Problem | ATC Human Performance |
| Air Traffic Incident | Operational Error |
Narrative:
I was working the de lancy (dn) sector (24 radar) while relieving the previous controller frequency 128.67 main and standby failed. Buec had a bad hum when I transmitted, so the supervisor gave me frequency 123.87. I switched 10 aircraft to 123.87 had air carrier X and air carrier Y. Advised primary frequency 128.67 was usable started to switch aircraft back (did not realize until later that air carrier Y stayed on 123.87). Air carrier X came over and I called traffic 10 O'clock 8 mi mlt at FL220. (Air carrier X at FL230.) when air carrier X verified on 128.67 I acknowledged and believed I cleared air carrier Y (over rockdale VOR on the swede 1 to bradley also at FL230) to descend and maintain FL190. After hearing tape playback air carrier X was cleared to FL190. When I saw air carrier X descending told air carrier X to maintain FL230 but radar associate, being relieved at this time, had frequencys locked open, could not get a readback that air carrier X received clearance to maintain FL230. When frequencys released air carrier X reported level at FL230.
Original NASA ASRS Text
Title: ATC EQUIP PROB RADIO WRONG ACFT ACR X DSCNT THROUGH OCCUPIED ALT HAD LTSS FROM MLT. SYS ERROR.
Narrative: I WAS WORKING THE DE LANCY (DN) SECTOR (24 RADAR) WHILE RELIEVING THE PREVIOUS CTLR FREQ 128.67 MAIN AND STANDBY FAILED. BUEC HAD A BAD HUM WHEN I XMITTED, SO THE SUPVR GAVE ME FREQ 123.87. I SWITCHED 10 ACFT TO 123.87 HAD ACR X AND ACR Y. ADVISED PRIMARY FREQ 128.67 WAS USABLE STARTED TO SWITCH ACFT BACK (DID NOT REALIZE UNTIL LATER THAT ACR Y STAYED ON 123.87). ACR X CAME OVER AND I CALLED TFC 10 O'CLOCK 8 MI MLT AT FL220. (ACR X AT FL230.) WHEN ACR X VERIFIED ON 128.67 I ACKNOWLEDGED AND BELIEVED I CLRED ACR Y (OVER ROCKDALE VOR ON THE SWEDE 1 TO BRADLEY ALSO AT FL230) TO DSND AND MAINTAIN FL190. AFTER HEARING TAPE PLAYBACK ACR X WAS CLRED TO FL190. WHEN I SAW ACR X DSNDING TOLD ACR X TO MAINTAIN FL230 BUT RADAR ASSOCIATE, BEING RELIEVED AT THIS TIME, HAD FREQS LOCKED OPEN, COULD NOT GET A READBACK THAT ACR X RECEIVED CLRNC TO MAINTAIN FL230. WHEN FREQS RELEASED ACR X RPTED LEVEL AT FL230.
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.