B757 first officer reports altitude assignment misunderstanding with chinese ATC.

Attributes
ACN	721729
Time
Date	200612
Place
Locale Reference	airport : zsqd.airport
State Reference	FO
Altitude	msl single value : 12500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zzz.artcc tower : den.tower
Operator	common carrier : air carrier
Make Model Name	B757 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	descent : approach
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Experience	flight time last 90 days : 66 flight time total : 10000 flight time type : 5000
ASRS Report	721729
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : airborne less severe non adherence : clearance
Independent Detector	other controllera
Resolutory Action	none taken : detected after the fact
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	ATC Human Performance Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

The ATC official; acting as an interpreter for the local ATC supervisor; asked me why we were at 3800 meters when we were cleared to 4800 meters on arrival. He said that we had a conflict with an airbus 320. I could not recall any indication from ATC during the arrival that we were at the wrong altitude. I told him that we must have thought we were cleared to 3800 meters (12467 ft) if we descended to 3800 meters. He said he listened to the tape and that we read back 4800 meters (15467 ft). I am at a loss to provide more details because I don't have them; and I am genuinely puzzled by the issues raised by the chinese. To the best of my knowledge; we complied with all ATC instructions throughout the flight. If we grant that an altitude deviation occurred then I believe that fatigue due to circadian rhythm shifts may be a factor as I am; at this time unable to recollect the issue that the chinese raise. The meeting was entirely congenial and friendly.

Original NASA ASRS Text

Title: B757 FO RPTS ALT ASSIGNMENT MISUNDERSTANDING WITH CHINESE ATC.

Narrative: THE ATC OFFICIAL; ACTING AS AN INTERPRETER FOR THE LCL ATC SUPVR; ASKED ME WHY WE WERE AT 3800 METERS WHEN WE WERE CLRED TO 4800 METERS ON ARR. HE SAID THAT WE HAD A CONFLICT WITH AN AIRBUS 320. I COULD NOT RECALL ANY INDICATION FROM ATC DURING THE ARR THAT WE WERE AT THE WRONG ALT. I TOLD HIM THAT WE MUST HAVE THOUGHT WE WERE CLRED TO 3800 METERS (12467 FT) IF WE DSNDED TO 3800 METERS. HE SAID HE LISTENED TO THE TAPE AND THAT WE READ BACK 4800 METERS (15467 FT). I AM AT A LOSS TO PROVIDE MORE DETAILS BECAUSE I DON'T HAVE THEM; AND I AM GENUINELY PUZZLED BY THE ISSUES RAISED BY THE CHINESE. TO THE BEST OF MY KNOWLEDGE; WE COMPLIED WITH ALL ATC INSTRUCTIONS THROUGHOUT THE FLT. IF WE GRANT THAT AN ALTDEV OCCURRED THEN I BELIEVE THAT FATIGUE DUE TO CIRCADIAN RHYTHM SHIFTS MAY BE A FACTOR AS I AM; AT THIS TIME UNABLE TO RECOLLECT THE ISSUE THAT THE CHINESE RAISE. THE MEETING WAS ENTIRELY CONGENIAL AND FRIENDLY.

Data retrieved from NASA's ASRS site as of January 2009 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.