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An A320 in ZDC airspace takes another aircraft altitude clearance and descends 1200 ft below proper altitude before taking corrective action back to assigned altitude.
| Attributes | |
| ACN | 392068 |
| Time | |
| Date | 199801 |
| Day | Mon |
| Local Time Of Day | 0601 To 1200 |
| Place | |
| Locale Reference | atc facility : gve |
| State Reference | VA |
| Altitude | msl bound lower : 35800 msl bound upper : 37000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | artcc : zdc tower : las |
| Operator | common carrier : air carrier |
| Make Model Name | A320 |
| Operating Under FAR Part | Part 121 |
| Navigation In Use | Other Other |
| Flight Phase | cruise other |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 250 flight time total : 4000 flight time type : 400 |
| ASRS Report | 392068 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 180 flight time total : 17200 flight time type : 760 |
| ASRS Report | 392060 |
| Events | |
| Anomaly | altitude deviation : excursion from assigned altitude non adherence : clearance other anomaly other |
| Independent Detector | atc equipment other atc equipment : unspecified other controllera |
| Resolutory Action | flight crew : returned to intended course or assigned course |
| Consequence | Other |
| Supplementary | |
| Primary Problem | Flight Crew Human Performance |
| Air Traffic Incident | Pilot Deviation |
Narrative:
Accepted and read back clearance to descend to FL350. Clearance was apparently meant for another aircraft. Controller caught altitude at FL358. Climbed back to FL370. No traffic conflict. Supplemental information from acn 392060: I left the cockpit for 3 mins to attend to physiological needs. When I returned, the first officer advised me he had mistakenly heard a descent clearance to FL350. ZDC inquired as to his altitude, and it became obvious then that the clearance was for another aircraft. Contributing to this problem, in addition to the lack of redundancy when only one crew member is in the loop, is the fact that when wearing the oxygen mask, ones breathing tends to obscure radio reception to some degree, as the flow of oxygen is somewhat loud. The first officer acknowledged that he should have waited to begin the descent until verification of the clearance was received.
Original NASA ASRS Text
Title: AN A320 IN ZDC AIRSPACE TAKES ANOTHER ACFT ALT CLRNC AND DSNDS 1200 FT BELOW PROPER ALT BEFORE TAKING CORRECTIVE ACTION BACK TO ASSIGNED ALT.
Narrative: ACCEPTED AND READ BACK CLRNC TO DSND TO FL350. CLRNC WAS APPARENTLY MEANT FOR ANOTHER ACFT. CTLR CAUGHT ALT AT FL358. CLBED BACK TO FL370. NO TFC CONFLICT. SUPPLEMENTAL INFO FROM ACN 392060: I LEFT THE COCKPIT FOR 3 MINS TO ATTEND TO PHYSIOLOGICAL NEEDS. WHEN I RETURNED, THE FO ADVISED ME HE HAD MISTAKENLY HEARD A DSCNT CLRNC TO FL350. ZDC INQUIRED AS TO HIS ALT, AND IT BECAME OBVIOUS THEN THAT THE CLRNC WAS FOR ANOTHER ACFT. CONTRIBUTING TO THIS PROB, IN ADDITION TO THE LACK OF REDUNDANCY WHEN ONLY ONE CREW MEMBER IS IN THE LOOP, IS THE FACT THAT WHEN WEARING THE OXYGEN MASK, ONES BREATHING TENDS TO OBSCURE RADIO RECEPTION TO SOME DEG, AS THE FLOW OF OXYGEN IS SOMEWHAT LOUD. THE FO ACKNOWLEDGED THAT HE SHOULD HAVE WAITED TO BEGIN THE DSCNT UNTIL VERIFICATION OF THE CLRNC WAS RECEIVED.
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.