Air carrier medium large transport clearance interpretation. Altitude excursion from assigned.

Attributes
ACN	88926
Time
Date	198806
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : atl
State Reference	GA
Altitude	msl bound lower : 12000 msl bound upper : 13000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zil
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	cruise other
Route In Use	arrival other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	88926
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : clearance other anomaly other
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance
Consequence	Other
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

On descent for atlanta cleared to cross 40 miles at 13000' 250 KTS next clearance was expect clearance to runway 8L at 40 miles descend to 9000' - clearance was understood - expect clearance stet...descend to 9000'. Controller intended clearance was expect clearance to runway 8L...at 40 miles descend to 9000'. Descended to 12000' before controller caught it and cleared us to 12000'.

Original NASA ASRS Text

Title: ACR MLG CLRNC INTERP. ALT EXCURSION FROM ASSIGNED.

Narrative: ON DESCENT FOR ATLANTA CLRED TO CROSS 40 MILES AT 13000' 250 KTS NEXT CLRNC WAS EXPECT CLRNC TO RWY 8L AT 40 MILES DESCEND TO 9000' - CLRNC WAS UNDERSTOOD - EXPECT CLRNC STET...DESCEND TO 9000'. CTLR INTENDED CLRNC WAS EXPECT CLRNC TO RWY 8L...AT 40 MILES DESCEND TO 9000'. DESCENDED TO 12000' BEFORE CTLR CAUGHT IT AND CLRED US TO 12000'.

Data retrieved from NASA's ASRS site as of August 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.