Jet transport crew misinterprets clearance. Climbs through assigned altitude in phl airspace.

Attributes
ACN	403720
Time
Date	199805
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : phl
State Reference	PA
Altitude	msl bound lower : 10000 msl bound upper : 12500
Environment
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : phl
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	climbout : intermediate altitude
Route In Use	departure other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	403720
Person 2
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Events
Anomaly	altitude deviation : overshoot non adherence : clearance other anomaly other
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	other

Narrative:

Misunderstanding about assigned altitude. Crew thought we were cleared to 14000 ft. ATC said 10000 ft. ATC brought it to our attention as we were climbing through 12500 ft. Then received new clearance to 13000 ft.

Original NASA ASRS Text

Title: JET TRANSPORT CREW MISINTERPRETS CLRNC. CLBS THROUGH ASSIGNED ALT IN PHL AIRSPACE.

Narrative: MISUNDERSTANDING ABOUT ASSIGNED ALT. CREW THOUGHT WE WERE CLRED TO 14000 FT. ATC SAID 10000 FT. ATC BROUGHT IT TO OUR ATTN AS WE WERE CLBING THROUGH 12500 FT. THEN RECEIVED NEW CLRNC TO 13000 FT.

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.