Narrative:

During departure eastbound lax and bos, departure control had cleared us to 17000 ft. 65 mi east of sli the GPWS announced pull up terrain repeatedly. At first we ignored the alert but the intensity and volume of the alert became more intense so we began to climb to FL180. At the same moment we advised departure control and they turned us over to lax center who immediately cleared us to FL230. We were advised by departure control prior to the frequency change that they were trying to contact us, but neither the captain, first officer or the jumpseat rider, (a controller), had heard any calls for us. In retrospect, the climb was not necessary, we knew that mountains were in the vicinity but we were not positive of their height. The ground proximity warning system gave us further false warning later in the flight.

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Original NASA ASRS Text

Title: FLC OF ACR WDB IN CRUISE CLB AT 17000 MSL CLB WITHOUT CLRNC IN RESPONSE TO FALSE GPWS.

Narrative: DURING DEP EBOUND LAX AND BOS, DEP CTL HAD CLRED US TO 17000 FT. 65 MI E OF SLI THE GPWS ANNOUNCED PULL UP TERRAIN REPEATEDLY. AT FIRST WE IGNORED THE ALERT BUT THE INTENSITY AND VOLUME OF THE ALERT BECAME MORE INTENSE SO WE BEGAN TO CLB TO FL180. AT THE SAME MOMENT WE ADVISED DEP CTL AND THEY TURNED US OVER TO LAX CTR WHO IMMEDIATELY CLRED US TO FL230. WE WERE ADVISED BY DEP CTL PRIOR TO THE FREQ CHANGE THAT THEY WERE TRYING TO CONTACT US, BUT NEITHER THE CAPT, FO OR THE JUMPSEAT RIDER, (A CTLR), HAD HEARD ANY CALLS FOR US. IN RETROSPECT, THE CLB WAS NOT NECESSARY, WE KNEW THAT MOUNTAINS WERE IN THE VICINITY BUT WE WERE NOT POSITIVE OF THEIR HEIGHT. THE GND PROX WARNING SYS GAVE US FURTHER FALSE WARNING LATER IN THE FLT.

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.