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Air carrier large transport requests clearance to lower altitude due turbulence, then in descent controller says maintain altitude without specifying altitude. Similar a/north in the area, and after identification confirmation, the reporter was cleared again to descend as requested.
| Attributes | |
| ACN | 133982 |
| Time | |
| Date | 199001 |
| Day | Wed |
| Local Time Of Day | 1201 To 1800 |
| Place | |
| Locale Reference | atc facility : lit |
| State Reference | AK |
| Altitude | msl bound lower : 26000 msl bound upper : 27000 |
| Environment | |
| Flight Conditions | IMC |
| Light | Dusk |
| Aircraft 1 | |
| Controlling Facilities | artcc : zme |
| Operator | common carrier : air carrier |
| Make Model Name | Large Transport, Low Wing, 3 Turbojet Eng |
| Flight Phase | cruise other cruise other descent other |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : cfi pilot : atp |
| Experience | flight time last 90 days : 210 flight time total : 16500 flight time type : 5210 |
| ASRS Report | 133982 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : second officer |
| Qualification | pilot : atp pilot : flight engineer |
| Experience | flight time last 90 days : 220 flight time total : 2675 flight time type : 975 |
| ASRS Report | 133976 |
| Events | |
| Anomaly | altitude deviation : excursion from assigned altitude inflight encounter other non adherence : clearance |
| Independent Detector | other flight crewa |
| Resolutory Action | controller : issued new clearance |
| Consequence | Other |
| Supplementary | |
| Primary Problem | Ambiguous |
| Air Traffic Incident | Operational Deviation Pilot Deviation other |
Narrative:
Flight ggch en route from dfw-lit. At FL270 we encountered moderate turbulence. We requested a lower altitude and received a clearance to maintain FL240 at pilot's discretion. We reported leaving FL270 after reading back our clearance. After passing FL260 center told us to maintain our altitude. We asked which altitude, with no reply. We immediately climbed back to FL270. We reported level at FL270. The controller called us gcch, which we corrected. We then again received a clearance to FL240. We descended to FL240 and asked the controller if there was a problem. He answered no problem. The rest of the flight was routine. There did not seem to be any actual altitude conflict, only a possible confusion on our call sign. Supplemental information from acn 133976: to be on the safe side, we climbed back up to FL270. When the controller did call back, he called us gcch instead of ggch, and again said to maintain altitude. The first officer corrected the call sign and was told to again descend to FL240.
Original NASA ASRS Text
Title: ACR LGT REQUESTS CLRNC TO LOWER ALT DUE TURBULENCE, THEN IN DESCENT CTLR SAYS MAINTAIN ALT WITHOUT SPECIFYING ALT. SIMILAR A/N IN THE AREA, AND AFTER IDENTIFICATION CONFIRMATION, THE REPORTER WAS CLEARED AGAIN TO DESCEND AS REQUESTED.
Narrative: FLT GGCH ENRTE FROM DFW-LIT. AT FL270 WE ENCOUNTERED MODERATE TURB. WE REQUESTED A LOWER ALT AND RECEIVED A CLRNC TO MAINTAIN FL240 AT PLT'S DISCRETION. WE REPORTED LEAVING FL270 AFTER READING BACK OUR CLRNC. AFTER PASSING FL260 CENTER TOLD US TO MAINTAIN OUR ALT. WE ASKED WHICH ALT, WITH NO REPLY. WE IMMEDIATELY CLBED BACK TO FL270. WE RPTED LEVEL AT FL270. THE CTLR CALLED US GCCH, WHICH WE CORRECTED. WE THEN AGAIN RECEIVED A CLRNC TO FL240. WE DSNDED TO FL240 AND ASKED THE CTLR IF THERE WAS A PROB. HE ANSWERED NO PROB. THE REST OF THE FLT WAS ROUTINE. THERE DID NOT SEEM TO BE ANY ACTUAL ALT CONFLICT, ONLY A POSSIBLE CONFUSION ON OUR CALL SIGN. SUPPLEMENTAL INFO FROM ACN 133976: TO BE ON THE SAFE SIDE, WE CLBED BACK UP TO FL270. WHEN THE CTLR DID CALL BACK, HE CALLED US GCCH INSTEAD OF GGCH, AND AGAIN SAID TO MAINTAIN ALT. THE F/O CORRECTED THE CALL SIGN AND WAS TOLD TO AGAIN DSND TO FL240.
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.