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Clearance interpretation problem where flight crew readback crossing altitude at 1 intersection, controller claimed read back for different intersection. Missed crossing restriction.
| Attributes | |
| ACN | 218490 |
| Time | |
| Date | 199208 |
| Day | Sun |
| Local Time Of Day | 1801 To 2400 |
| Place | |
| Locale Reference | atc facility : atl |
| State Reference | GA |
| Altitude | msl bound lower : 13000 msl bound upper : 14600 |
| Environment | |
| Flight Conditions | Mixed |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | artcc : ztl |
| Operator | common carrier : air carrier |
| Make Model Name | Large Transport, Low Wing, 2 Turbojet Eng |
| Navigation In Use | Other Other |
| Flight Phase | descent : approach descent other |
| Route In Use | arrival star : star |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : instrument pilot : commercial pilot : atp pilot : flight engineer |
| Experience | flight time last 90 days : 150 flight time total : 11000 flight time type : 2000 |
| ASRS Report | 218490 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Events | |
| Anomaly | altitude deviation : crossing restriction not met non adherence : clearance other anomaly other |
| Independent Detector | other controllera other flight crewa |
| Resolutory Action | none taken : anomaly accepted |
| Consequence | faa : reviewed incident with flight crew |
| Supplementary | |
| Primary Problem | Ambiguous |
| Air Traffic Incident | other |
Narrative:
Flight was cleared to descend and cross womac intersection on the macey arrival into atlanta. This clearance was understood by both pilots and read back to the controller. The altitude alerter was set for 13000 ft and the restriction was programmed into the FMS. Just prior to macey we received a TCASII TA on an aircraft less than 2000 ft above us. ATC requested our position which we reported as directly over macey. Our altitude was 14600. About 2 mins later the controller advised us that we had been cleared to cross macey at 13000 ft. The captain tried twice to explain that we had copied and read back 'womac at 13000' which the controller did not understand. He continued to misunderstand the captain to be saying 'macey.' I clarified this to the controller by spelling 'womac' to him. He said we did not read back 'womac.' we both believe we were cleared to cross womac at 13000 ft as the STAR says to expect. A contributing factor is the poor quality of transmissions received from this controller. He was very soft spoken and other controllers and aircraft transmissions in the backgnd were quite loud. He also appeared to be having trouble understanding our transmissions.
Original NASA ASRS Text
Title: CLRNC INTERP PROBLEM WHERE FLC READBACK XING ALT AT 1 INTXN, CTLR CLAIMED READ BACK FOR DIFFERENT INTXN. MISSED XING RESTRICTION.
Narrative: FLT WAS CLRED TO DSND AND CROSS WOMAC INTXN ON THE MACEY ARR INTO ATLANTA. THIS CLRNC WAS UNDERSTOOD BY BOTH PLTS AND READ BACK TO THE CTLR. THE ALT ALERTER WAS SET FOR 13000 FT AND THE RESTRICTION WAS PROGRAMMED INTO THE FMS. JUST PRIOR TO MACEY WE RECEIVED A TCASII TA ON AN ACFT LESS THAN 2000 FT ABOVE US. ATC REQUESTED OUR POS WHICH WE RPTED AS DIRECTLY OVER MACEY. OUR ALT WAS 14600. ABOUT 2 MINS LATER THE CTLR ADVISED US THAT WE HAD BEEN CLRED TO CROSS MACEY AT 13000 FT. THE CAPT TRIED TWICE TO EXPLAIN THAT WE HAD COPIED AND READ BACK 'WOMAC AT 13000' WHICH THE CTLR DID NOT UNDERSTAND. HE CONTINUED TO MISUNDERSTAND THE CAPT TO BE SAYING 'MACEY.' I CLARIFIED THIS TO THE CTLR BY SPELLING 'WOMAC' TO HIM. HE SAID WE DID NOT READ BACK 'WOMAC.' WE BOTH BELIEVE WE WERE CLRED TO CROSS WOMAC AT 13000 FT AS THE STAR SAYS TO EXPECT. A CONTRIBUTING FACTOR IS THE POOR QUALITY OF TRANSMISSIONS RECEIVED FROM THIS CTLR. HE WAS VERY SOFT SPOKEN AND OTHER CTLRS AND ACFT TRANSMISSIONS IN THE BACKGND WERE QUITE LOUD. HE ALSO APPEARED TO BE HAVING TROUBLE UNDERSTANDING OUR TRANSMISSIONS.
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.