Narrative:

Captain's emergency authority/authorized, WX deviation. Flight encounter line of unforecast cumulo nimbus 20 mins after takeoff. We deviated west to parallel line looking for a break to punch through. Never found one. We operated 40-70 NM south of line for over 400 NM until we reached the end of the line. During this period, despite being 50 NM from the line, we encountered moderate turbulence, heavy static discharges and lightning. Static buildup was so bad, both VHF receivers were unusable. I had the first officer broadcasting on all frequencys (121.5, etc, etc) our position and intentions. I descended to FL320 in a successful attempt to reduce our exposure to turbulence and static/lightning discharges. After about 45 mins of radio deafness, we regained contact with cordoba center. They had heard our broadcasts and cleared us as requested to rejoin our fpr. Aircraft was not known to be damaged by discharges and 75 mins after takeoff, flight attendants were allowed to get out of their seats to begin service. This entire miserable event could have been avoided had dispatch provided us with timely satellite WX data which would have shown that an easy eastern deviation would have taken us clear of the WX with little effort. Dispatch was debriefed via satcom once clear of WX. He told me that this line had flared up in the last 2 hours and apologized for not sending us current data. Sbound flight was advised by us upon passing. Flight landed without incident approximately 20 mins later.

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Original NASA ASRS Text

Title: B777-200 CREW ENCOUNTERED A SOLID LINE OF TSTMS, OVER 400 MI LONG. THIS REQUIRED BROADCASTING DEV INTENTIONS IN THE BLIND AS THE VHF RADIOS WERE RENDERED INOP BY STATIC.

Narrative: CAPT'S EMER AUTH, WX DEV. FLT ENCOUNTER LINE OF UNFORECAST CUMULO NIMBUS 20 MINS AFTER TKOF. WE DEVIATED W TO PARALLEL LINE LOOKING FOR A BREAK TO PUNCH THROUGH. NEVER FOUND ONE. WE OPERATED 40-70 NM S OF LINE FOR OVER 400 NM UNTIL WE REACHED THE END OF THE LINE. DURING THIS PERIOD, DESPITE BEING 50 NM FROM THE LINE, WE ENCOUNTERED MODERATE TURB, HVY STATIC DISCHARGES AND LIGHTNING. STATIC BUILDUP WAS SO BAD, BOTH VHF RECEIVERS WERE UNUSABLE. I HAD THE FO BROADCASTING ON ALL FREQS (121.5, ETC, ETC) OUR POS AND INTENTIONS. I DSNDED TO FL320 IN A SUCCESSFUL ATTEMPT TO REDUCE OUR EXPOSURE TO TURB AND STATIC/LIGHTNING DISCHARGES. AFTER ABOUT 45 MINS OF RADIO DEAFNESS, WE REGAINED CONTACT WITH CORDOBA CTR. THEY HAD HEARD OUR BROADCASTS AND CLRED US AS REQUESTED TO REJOIN OUR FPR. ACFT WAS NOT KNOWN TO BE DAMAGED BY DISCHARGES AND 75 MINS AFTER TKOF, FLT ATTENDANTS WERE ALLOWED TO GET OUT OF THEIR SEATS TO BEGIN SVC. THIS ENTIRE MISERABLE EVENT COULD HAVE BEEN AVOIDED HAD DISPATCH PROVIDED US WITH TIMELY SATELLITE WX DATA WHICH WOULD HAVE SHOWN THAT AN EASY EASTERN DEV WOULD HAVE TAKEN US CLR OF THE WX WITH LITTLE EFFORT. DISPATCH WAS DEBRIEFED VIA SATCOM ONCE CLR OF WX. HE TOLD ME THAT THIS LINE HAD FLARED UP IN THE LAST 2 HRS AND APOLOGIZED FOR NOT SENDING US CURRENT DATA. SBOUND FLT WAS ADVISED BY US UPON PASSING. FLT LANDED WITHOUT INCIDENT APPROX 20 MINS LATER.

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.