Narrative:

The ATC clearance received prior to engine start for this flight to denver contained a turn after takeoff from runway 30 to 180 degree. The captain and I both heard and acknowledged the clearance. During the taxi out for takeoff we discussed the departure in some detail including our understanding that it was a right turn to 180. Even though this was the long way around, we both noted that our route of flight to denver was to the east (towards thermal VORTAC) and thus to the right. This was further confirmed by reference to the map display on our electronic flight instruments. Consequently neither of us questioned the turn direction. We both felt that we copied the clearance correctly. Apparently, it was a case of hearing what we expected, which was, as it turned out, in error. Upon contacting coast approach after takeoff as we started our right turn, we were informed of our error, reversed our turn and followed the controller's instructions. Although we may have acknowledged and copied the clearance properly some 20 mins earlier, our obvious reversal of the turn direction could have been eliminated by either having the tower issue or verify the turn direction and heading (we were the only air carrier departure at this time) or charting this clearance (ie, a SID) if it is routinely used for eastbound departures from long beach. It was the first time into long beach for both of us and a more formal presentation of this departure would have been of considerable value.

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Original NASA ASRS Text

Title: FLT CREW OF MLG DEPARTING LGB ALLEGEDLY MISREAD THEIR CLRNC AND TURNED WRONG WAY AFTER TKOF.

Narrative: THE ATC CLRNC RECEIVED PRIOR TO ENGINE START FOR THIS FLT TO DENVER CONTAINED A TURN AFTER TKOF FROM RWY 30 TO 180 DEG. THE CAPT AND I BOTH HEARD AND ACKNOWLEDGED THE CLRNC. DURING THE TAXI OUT FOR TKOF WE DISCUSSED THE DEP IN SOME DETAIL INCLUDING OUR UNDERSTANDING THAT IT WAS A RIGHT TURN TO 180. EVEN THOUGH THIS WAS THE LONG WAY AROUND, WE BOTH NOTED THAT OUR ROUTE OF FLT TO DENVER WAS TO THE EAST (TOWARDS THERMAL VORTAC) AND THUS TO THE RIGHT. THIS WAS FURTHER CONFIRMED BY REFERENCE TO THE MAP DISPLAY ON OUR ELECTRONIC FLT INSTRUMENTS. CONSEQUENTLY NEITHER OF US QUESTIONED THE TURN DIRECTION. WE BOTH FELT THAT WE COPIED THE CLRNC CORRECTLY. APPARENTLY, IT WAS A CASE OF HEARING WHAT WE EXPECTED, WHICH WAS, AS IT TURNED OUT, IN ERROR. UPON CONTACTING COAST APCH AFTER TKOF AS WE STARTED OUR RIGHT TURN, WE WERE INFORMED OF OUR ERROR, REVERSED OUR TURN AND FOLLOWED THE CTLR'S INSTRUCTIONS. ALTHOUGH WE MAY HAVE ACKNOWLEDGED AND COPIED THE CLRNC PROPERLY SOME 20 MINS EARLIER, OUR OBVIOUS REVERSAL OF THE TURN DIRECTION COULD HAVE BEEN ELIMINATED BY EITHER HAVING THE TWR ISSUE OR VERIFY THE TURN DIRECTION AND HDG (WE WERE THE ONLY AIR CARRIER DEP AT THIS TIME) OR CHARTING THIS CLRNC (IE, A SID) IF IT IS ROUTINELY USED FOR EBND DEPS FROM LONG BEACH. IT WAS THE FIRST TIME INTO LONG BEACH FOR BOTH OF US AND A MORE FORMAL PRESENTATION OF THIS DEP WOULD HAVE BEEN OF CONSIDERABLE VALUE.

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.