Large transport turns wrong direction after takeoff, misinterpreted clearance.

Attributes
ACN	318800
Time
Date	199510
Day	Wed
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : ord
State Reference	IL
Altitude	agl bound lower : 500 agl bound upper : 500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : ord
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	climbout : takeoff climbout : initial
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial pilot : flight engineer
Experience	flight time last 90 days : 210 flight time total : 7800 flight time type : 210
ASRS Report	318800
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	non adherence : far non adherence : clearance other spatial deviation
Independent Detector	other controllera
Resolutory Action	flight crew : returned to intended course or assigned course other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

We were cleared for departure by ord tower. We were told to fly heading 330 degrees, we understood 030 degrees. In the middle of the turn, tower called and said heading 330 degrees was the correct heading. We corrected immediately. All instructions at ord on tower and approach are read so quickly that errors are easy to make by all.

Original NASA ASRS Text

Title: LGT TURNS WRONG DIRECTION AFTER TKOF, MISINTERPRETED CLRNC.

Narrative: WE WERE CLRED FOR DEP BY ORD TWR. WE WERE TOLD TO FLY HDG 330 DEGS, WE UNDERSTOOD 030 DEGS. IN THE MIDDLE OF THE TURN, TWR CALLED AND SAID HDG 330 DEGS WAS THE CORRECT HDG. WE CORRECTED IMMEDIATELY. ALL INSTRUCTIONS AT ORD ON TWR AND APCH ARE READ SO QUICKLY THAT ERRORS ARE EASY TO MAKE BY ALL.

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.