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37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
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Air carrier X had less than standard separation from Y because of stuck microphone. System error.
| Attributes | |
| ACN | 285354 |
| Time | |
| Date | 199410 |
| Day | Tue |
| Local Time Of Day | 1801 To 2400 |
| Place | |
| Locale Reference | atc facility : maw |
| State Reference | MO |
| Altitude | msl bound lower : 37000 msl bound upper : 37000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | artcc : zme |
| Operator | common carrier : air carrier |
| Make Model Name | Commercial Fixed Wing |
| Operating Under FAR Part | Part 121 |
| Navigation In Use | Other |
| Flight Phase | cruise other |
| Route In Use | enroute : direct |
| Flight Plan | IFR |
| Aircraft 2 | |
| Make Model Name | Commercial Fixed Wing |
| Operating Under FAR Part | other : unknown |
| Flight Phase | cruise other |
| Route In Use | enroute : direct |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 180 flight time total : 13000 flight time type : 3500 |
| ASRS Report | 285354 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : commercial pilot : instrument |
| Events | |
| Anomaly | aircraft equipment problem : less severe conflict : airborne less severe non adherence : published procedure non adherence other |
| Independent Detector | aircraft equipment other aircraft equipment : unspecified other flight crewa |
| Resolutory Action | controller : issued new clearance other |
| Consequence | faa : investigated |
| Miss Distance | horizontal : 18000 vertical : 0 |
| Supplementary | |
| Primary Problem | Aircraft |
| Air Traffic Incident | Operational Error |
Narrative:
En route between maw and vuz vors. Clear sky, level at FL370. Last clearance: 'fly heading 140 degrees until receiving vulcan, then proceed direct.' working with ZME on 118.62. Air carrier X experienced several mins during which it appeared that there was a 'stuck microphone' on the frequency. All xmissions on the frequency were garbled and totally unreadable. We elected to try to re-establish contact with ZME on another frequency selected from the high altitude en route chart. The first frequency resulted in contact with nashville approach, who directed us to ZTL, who then passed us on to a correct frequency for ZME. Between each of these frequency changes, we reselected 118.62 and continued to find the 'stuck microphone' situation existing. As we were re-establishing contact with ZME (127.37) we received a TCASII alert (TA) and observed an aircraft Y at our altitude pass our nose from right to left about 3-4 mi away. ZME told us to turn to heading 180 degrees. We started the turn and advised ZME we had the traffic in visual contact. ZME cleared us back on flight plan. A potentially hazardous situation was presented because there is no procedure for re-establishing contact with ATC during a 'stuck microphone' situation. Backup frequencys could be published on the en route charts (ie, 118.62 (127.37)) -- indicating if a problem develops on 118.62 attempt contact on 127.37. Also check high altitude chart to assure frequencys given are valid.
Original NASA ASRS Text
Title: ACR X HAD LTSS FROM Y BECAUSE OF STUCK MIKE. SYS ERROR.
Narrative: ENRTE BTWN MAW AND VUZ VORS. CLR SKY, LEVEL AT FL370. LAST CLRNC: 'FLY HDG 140 DEGS UNTIL RECEIVING VULCAN, THEN PROCEED DIRECT.' WORKING WITH ZME ON 118.62. ACR X EXPERIENCED SEVERAL MINS DURING WHICH IT APPEARED THAT THERE WAS A 'STUCK MIKE' ON THE FREQ. ALL XMISSIONS ON THE FREQ WERE GARBLED AND TOTALLY UNREADABLE. WE ELECTED TO TRY TO RE-ESTABLISH CONTACT WITH ZME ON ANOTHER FREQ SELECTED FROM THE HIGH ALT ENRTE CHART. THE FIRST FREQ RESULTED IN CONTACT WITH NASHVILLE APCH, WHO DIRECTED US TO ZTL, WHO THEN PASSED US ON TO A CORRECT FREQ FOR ZME. BTWN EACH OF THESE FREQ CHANGES, WE RESELECTED 118.62 AND CONTINUED TO FIND THE 'STUCK MIKE' SIT EXISTING. AS WE WERE RE-ESTABLISHING CONTACT WITH ZME (127.37) WE RECEIVED A TCASII ALERT (TA) AND OBSERVED AN ACFT Y AT OUR ALT PASS OUR NOSE FROM R TO L ABOUT 3-4 MI AWAY. ZME TOLD US TO TURN TO HDG 180 DEGS. WE STARTED THE TURN AND ADVISED ZME WE HAD THE TFC IN VISUAL CONTACT. ZME CLRED US BACK ON FLT PLAN. A POTENTIALLY HAZARDOUS SIT WAS PRESENTED BECAUSE THERE IS NO PROC FOR RE-ESTABLISHING CONTACT WITH ATC DURING A 'STUCK MIKE' SIT. BACKUP FREQS COULD BE PUBLISHED ON THE ENRTE CHARTS (IE, 118.62 (127.37)) -- INDICATING IF A PROB DEVELOPS ON 118.62 ATTEMPT CONTACT ON 127.37. ALSO CHK HIGH ALT CHART TO ASSURE FREQS GIVEN ARE VALID.
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.