Narrative:

We had received a standard clearance from lih to hnl, cleared as filed; i.e., V15 hnl. On taxi-out in lih, the first officer got taxi clearance, then had to talk to company for final weight and balance revisions. While first officer spoke to company, I said I'd monitor ground control. I heard ground call and say to monitor tower, to which I replied 'monitor tower,' and our call sign. During climb out, while intercepting V15 (110 degree right) on a 125 degree heading, center called and asked what heading we were flying. First officer replied we were flying a 125 degree heading. Center then asked if we had received an 080 degree heading from lih tower. First officer replied no, since we had not. I know that neither the first officer nor I heard lih ground or tower give us an 080 degree heading after departure. Later I noticed on the particular aircraft we were flying that when 1 pilot keys his/her microphone, it lowers the vol on the other pilot's radio. I began to wonder if the ground controller, perhaps, may have said to fly 080 degree heading at the time the first officer was talking to company and I missed it. If that was the case, since I never read back the 080 degree heading, the controller should have confirmed that I heard the clearance. Lih ground or tower may have never even issued the heading, which makes this entire discussion moot; however, this brought up an important point: correct readback of a clearance is essential in assuring that the clearance (heading, altitude, etc) was received and received correctly. Lacking a correct readback, a clearance should be issued again, or clarified until read back correctly.

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Original NASA ASRS Text

Title: ACR MLG TRACK HEADING DEVIATION ON DEP CLIMB FROM LIH.

Narrative: WE HAD RECEIVED A STANDARD CLRNC FROM LIH TO HNL, CLRED AS FILED; I.E., V15 HNL. ON TAXI-OUT IN LIH, THE F/O GOT TAXI CLRNC, THEN HAD TO TALK TO COMPANY FOR FINAL WT AND BAL REVISIONS. WHILE F/O SPOKE TO COMPANY, I SAID I'D MONITOR GND CTL. I HEARD GND CALL AND SAY TO MONITOR TWR, TO WHICH I REPLIED 'MONITOR TWR,' AND OUR CALL SIGN. DURING CLBOUT, WHILE INTERCEPTING V15 (110 DEG R) ON A 125 DEG HDG, CENTER CALLED AND ASKED WHAT HDG WE WERE FLYING. F/O REPLIED WE WERE FLYING A 125 DEG HDG. CENTER THEN ASKED IF WE HAD RECEIVED AN 080 DEG HDG FROM LIH TWR. F/O REPLIED NO, SINCE WE HAD NOT. I KNOW THAT NEITHER THE F/O NOR I HEARD LIH GND OR TWR GIVE US AN 080 DEG HDG AFTER DEP. LATER I NOTICED ON THE PARTICULAR ACFT WE WERE FLYING THAT WHEN 1 PLT KEYS HIS/HER MIC, IT LOWERS THE VOL ON THE OTHER PLT'S RADIO. I BEGAN TO WONDER IF THE GND CTLR, PERHAPS, MAY HAVE SAID TO FLY 080 DEG HDG AT THE TIME THE F/O WAS TALKING TO COMPANY AND I MISSED IT. IF THAT WAS THE CASE, SINCE I NEVER READ BACK THE 080 DEG HDG, THE CTLR should HAVE CONFIRMED THAT I HEARD THE CLRNC. LIH GND OR TWR MAY HAVE NEVER EVEN ISSUED THE HDG, WHICH MAKES THIS ENTIRE DISCUSSION MOOT; HOWEVER, THIS BROUGHT UP AN IMPORTANT POINT: CORRECT READBACK OF A CLRNC IS ESSENTIAL IN ASSURING THAT THE CLRNC (HDG, ALT, ETC) WAS RECEIVED AND RECEIVED CORRECTLY. LACKING A CORRECT READBACK, A CLRNC SHOULD BE ISSUED AGAIN, OR CLARIFIED UNTIL READ BACK CORRECTLY.

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.