Narrative:

Flight was cleared for immediate takeoff on runway 27L and given the following climb clearance: 'cleared for takeoff. Turn 290 degrees until 3000', then back to 090 degrees.' I read back clearance with no corrections from tower. First officer made takeoff. At 300' he made a right turn to 290 degrees. At 3000', I selected a right turn (shorter distance to 090 degrees) on heading select and first officer began right turn. During this time we were given a frequency change to 125.0 ord departure control. Upon checking in he asked if we were starting our turn to 090 degrees. I stated, 'affirmative, right turn to 090 degrees, climbing to 5000'.' departure control then asked if tower had given us a right turn, because normally they give a left turn when landing on runway 14. Departure control then told us to continue turn to 120 degrees and said there was no conflict. Observations: ord tower did not actually request a left turn to 090 degrees, so I concluded the turn should be made the short way (right) to the heading. I knew ord was landing runway 14, but figured that was the reason for the delay until reaching 3000' MSL before commencing turn. In retrospect, his instruction 'back to 090 degrees' was meant to infer a left turn. However, this was not what I heard nor read back. In addition, this was a night takeoff with trw's in the area in a very light aircraft on a short leg to grr (25 mins), accompanied by a frequency change at the critical turn time. Due to the short flight time, high climb rate and demands at the time (radio's, checklists, radar tuning for WX, etc), I did not visualize what the tower was inferring for the departure climb. I feel, however, the tower should have delayed the frequency change to departure control until he observed us making the left turn, thereby reducing any potential conflicts.

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Original NASA ASRS Text

Title: ACR CLRNC CONFUSION. TURNED RIGHT WHEN CTLR EXPECTED LEFT.

Narrative: FLT WAS CLRED FOR IMMEDIATE TKOF ON RWY 27L AND GIVEN THE FOLLOWING CLB CLRNC: 'CLRED FOR TKOF. TURN 290 DEGS UNTIL 3000', THEN BACK TO 090 DEGS.' I READ BACK CLRNC WITH NO CORRECTIONS FROM TWR. F/O MADE TKOF. AT 300' HE MADE A RIGHT TURN TO 290 DEGS. AT 3000', I SELECTED A RIGHT TURN (SHORTER DISTANCE TO 090 DEGS) ON HDG SELECT AND F/O BEGAN RIGHT TURN. DURING THIS TIME WE WERE GIVEN A FREQ CHANGE TO 125.0 ORD DEP CTL. UPON CHKING IN HE ASKED IF WE WERE STARTING OUR TURN TO 090 DEGS. I STATED, 'AFFIRMATIVE, RIGHT TURN TO 090 DEGS, CLBING TO 5000'.' DEP CTL THEN ASKED IF TWR HAD GIVEN US A RIGHT TURN, BECAUSE NORMALLY THEY GIVE A LEFT TURN WHEN LNDG ON RWY 14. DEP CTL THEN TOLD US TO CONTINUE TURN TO 120 DEGS AND SAID THERE WAS NO CONFLICT. OBSERVATIONS: ORD TWR DID NOT ACTUALLY REQUEST A LEFT TURN TO 090 DEGS, SO I CONCLUDED THE TURN SHOULD BE MADE THE SHORT WAY (RIGHT) TO THE HDG. I KNEW ORD WAS LNDG RWY 14, BUT FIGURED THAT WAS THE REASON FOR THE DELAY UNTIL REACHING 3000' MSL BEFORE COMMENCING TURN. IN RETROSPECT, HIS INSTRUCTION 'BACK TO 090 DEGS' WAS MEANT TO INFER A LEFT TURN. HOWEVER, THIS WAS NOT WHAT I HEARD NOR READ BACK. IN ADDITION, THIS WAS A NIGHT TKOF WITH TRW'S IN THE AREA IN A VERY LIGHT ACFT ON A SHORT LEG TO GRR (25 MINS), ACCOMPANIED BY A FREQ CHANGE AT THE CRITICAL TURN TIME. DUE TO THE SHORT FLT TIME, HIGH CLB RATE AND DEMANDS AT THE TIME (RADIO'S, CHKLISTS, RADAR TUNING FOR WX, ETC), I DID NOT VISUALIZE WHAT THE TWR WAS INFERRING FOR THE DEP CLB. I FEEL, HOWEVER, THE TWR SHOULD HAVE DELAYED THE FREQ CHANGE TO DEP CTL UNTIL HE OBSERVED US MAKING THE LEFT TURN, THEREBY REDUCING ANY POTENTIAL CONFLICTS.

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.