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|
Attributes | |
ACN | 430223 |
Time | |
Date | 199903 |
Day | Mon |
Local Time Of Day | 1201 To 1800 |
Place | |
Locale Reference | airport : oejn.airport |
State Reference | FL |
Altitude | agl single value : 0 |
Environment | |
Flight Conditions | VMC |
Light | Daylight |
Aircraft 1 | |
Operator | common carrier : air carrier |
Make Model Name | B747 Undifferentiated or Other Model |
Operating Under FAR Part | Part 121 |
Flight Phase | ground : pushback |
Flight Plan | IFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Qualification | pilot : atp |
Experience | flight time last 90 days : 120 flight time total : 13200 flight time type : 7000 |
ASRS Report | 430223 |
Person 2 | |
Affiliation | company : air carrier |
Function | flight crew : first officer |
Qualification | pilot : instrument pilot : multi engine pilot : commercial |
Events | |
Anomaly | ground encounters other non adherence : clearance non adherence other |
Independent Detector | other controllera |
Resolutory Action | controller : issued new clearance flight crew : became reoriented none taken : anomaly accepted |
Supplementary | |
Problem Areas | ATC Human Performance |
Primary Problem | ATC Human Performance |
Air Traffic Incident | Operational Error |
Narrative:
After receiving start-up clearance, I requested pushback clearance from our parking spot. I thought jed ground said 'cleared for start and push,' and I read back the same. We pushed back the airplane and parked in the position abeam parking spot, parallel to taxiway B. My copilot was commanding all checklists and actions since it was his leg. After completing pushback, I suggested the engine start but my copilot said that we were still held for engine start, which he heard when we received the clearance 'cleared for the push but stand by for start' and that was exactly what the so heard, too. I called jed ground requesting engine start. He came back, 'you were cleared for start but not for pushback.' we were confused and looked at each other. Since the worst case scenario was we completely misunderstood the clearance, I said 'we thought we were cleared for the push and hold for start, but if we misunderstood it, we apologize.' he was not really happy what we did. Anyway, we were already pushed back in position without engine running. I had to ask one more time for engine start (because we thought we were not supposed to start engines until pushback). He said 'stand by,' and made several radio xmissions to other aircraft, then gave us taxi clearance. I told him we had to start engine first. He came back, 'you'd better do it now! I have traffic holding behind you.' we were still inside the apron not on the active taxiway. We did not know who was behind us in the apron. But when we finally taxied out onto taxiway U, we saw nobody behind us in the apron. Just before switching the radio to ted tower, I said one more time, 'we really, really apologize for the misunderstanding' and he said, 'it is just for your safety concern.' even though I still cannot determine whether we misunderstood him or he gave us the wrong clearance, and no one's safety was jeopardized nor no traffic conflict took place, the confusion could have been avoided if all of crew members listened to ATC more carefully and verified ambiguous and doubtful clearance.
Original NASA ASRS Text
Title: A B747 FLC AT JED, SAUDI ARABIA MISUNDERSTOOD CLRNC FOR PUSHBACK AND ENG START.
Narrative: AFTER RECEIVING START-UP CLRNC, I REQUESTED PUSHBACK CLRNC FROM OUR PARKING SPOT. I THOUGHT JED GND SAID 'CLRED FOR START AND PUSH,' AND I READ BACK THE SAME. WE PUSHED BACK THE AIRPLANE AND PARKED IN THE POS ABEAM PARKING SPOT, PARALLEL TO TXWY B. MY COPLT WAS COMMANDING ALL CHKLISTS AND ACTIONS SINCE IT WAS HIS LEG. AFTER COMPLETING PUSHBACK, I SUGGESTED THE ENG START BUT MY COPLT SAID THAT WE WERE STILL HELD FOR ENG START, WHICH HE HEARD WHEN WE RECEIVED THE CLRNC 'CLRED FOR THE PUSH BUT STAND BY FOR START' AND THAT WAS EXACTLY WHAT THE SO HEARD, TOO. I CALLED JED GND REQUESTING ENG START. HE CAME BACK, 'YOU WERE CLRED FOR START BUT NOT FOR PUSHBACK.' WE WERE CONFUSED AND LOOKED AT EACH OTHER. SINCE THE WORST CASE SCENARIO WAS WE COMPLETELY MISUNDERSTOOD THE CLRNC, I SAID 'WE THOUGHT WE WERE CLRED FOR THE PUSH AND HOLD FOR START, BUT IF WE MISUNDERSTOOD IT, WE APOLOGIZE.' HE WAS NOT REALLY HAPPY WHAT WE DID. ANYWAY, WE WERE ALREADY PUSHED BACK IN POS WITHOUT ENG RUNNING. I HAD TO ASK ONE MORE TIME FOR ENG START (BECAUSE WE THOUGHT WE WERE NOT SUPPOSED TO START ENGS UNTIL PUSHBACK). HE SAID 'STAND BY,' AND MADE SEVERAL RADIO XMISSIONS TO OTHER ACFT, THEN GAVE US TAXI CLRNC. I TOLD HIM WE HAD TO START ENG FIRST. HE CAME BACK, 'YOU'D BETTER DO IT NOW! I HAVE TFC HOLDING BEHIND YOU.' WE WERE STILL INSIDE THE APRON NOT ON THE ACTIVE TXWY. WE DID NOT KNOW WHO WAS BEHIND US IN THE APRON. BUT WHEN WE FINALLY TAXIED OUT ONTO TXWY U, WE SAW NOBODY BEHIND US IN THE APRON. JUST BEFORE SWITCHING THE RADIO TO TED TWR, I SAID ONE MORE TIME, 'WE REALLY, REALLY APOLOGIZE FOR THE MISUNDERSTANDING' AND HE SAID, 'IT IS JUST FOR YOUR SAFETY CONCERN.' EVEN THOUGH I STILL CANNOT DETERMINE WHETHER WE MISUNDERSTOOD HIM OR HE GAVE US THE WRONG CLRNC, AND NO ONE'S SAFETY WAS JEOPARDIZED NOR NO TFC CONFLICT TOOK PLACE, THE CONFUSION COULD HAVE BEEN AVOIDED IF ALL OF CREW MEMBERS LISTENED TO ATC MORE CAREFULLY AND VERIFIED AMBIGUOUS AND DOUBTFUL CLRNC.
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.