B767-400 flight crew has an altitude deviation on approach to atl.

Attributes
ACN	726160
Time
Date	200702
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : atl.airport
State Reference	GA
Altitude	msl single value : 7000
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : a80.tracon
Operator	common carrier : air carrier
Make Model Name	B767-400 and 400 ER
Operating Under FAR Part	Part 121
Flight Phase	descent : approach
Route In Use	arrival : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : multi engine pilot : commercial pilot : instrument pilot : atp
Experience	flight time last 90 days : 144 flight time total : 17000 flight time type : 1500
ASRS Report	726160
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	altitude deviation : overshoot non adherence : clearance other anomaly other
Independent Detector	other controllera other flight crewa
Resolutory Action	none taken : insufficient time
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance

Narrative:

We were being vectored for the ILS 9L at atl; on a southerly vector at 7000 ft MSL. We had already been given several altitude and heading changes; and were on a vector for the runway 9L localizer outside varnm. The controller cleared us for the approach; and to cross varnm at an altitude -- I thought he said 6000 ft. So I dialed the altitude in the MCP and hit flight level change as the copilot read back to the controller. The copilot read back 7000 ft; so I asked him to confirm the altitude. It took a little time for him to query the controller; and the airplane started its descent. When the controller responded; he said the clearance was to 7000 ft; but that were ok to stay at our altitude (approximately 6700). In retrospect; I was sure the controller had said 6000 ft; but it seems I misheard him. Another factor that may have contributed was the airport confign.

Original NASA ASRS Text

Title: B767-400 FLT CREW HAS AN ALTDEV ON APCH TO ATL.

Narrative: WE WERE BEING VECTORED FOR THE ILS 9L AT ATL; ON A SOUTHERLY VECTOR AT 7000 FT MSL. WE HAD ALREADY BEEN GIVEN SEVERAL ALT AND HDG CHANGES; AND WERE ON A VECTOR FOR THE RWY 9L LOC OUTSIDE VARNM. THE CTLR CLRED US FOR THE APCH; AND TO CROSS VARNM AT AN ALT -- I THOUGHT HE SAID 6000 FT. SO I DIALED THE ALT IN THE MCP AND HIT FLT LEVEL CHANGE AS THE COPLT READ BACK TO THE CTLR. THE COPLT READ BACK 7000 FT; SO I ASKED HIM TO CONFIRM THE ALT. IT TOOK A LITTLE TIME FOR HIM TO QUERY THE CTLR; AND THE AIRPLANE STARTED ITS DSCNT. WHEN THE CTLR RESPONDED; HE SAID THE CLRNC WAS TO 7000 FT; BUT THAT WERE OK TO STAY AT OUR ALT (APPROX 6700). IN RETROSPECT; I WAS SURE THE CTLR HAD SAID 6000 FT; BUT IT SEEMS I MISHEARD HIM. ANOTHER FACTOR THAT MAY HAVE CONTRIBUTED WAS THE ARPT CONFIGN.

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.