Narrative:

My first officer made a comment about only 2 en route alternates while working on our flight plan. I had seen that before and did not give it much consideration. We had adequate fuel for the trip -- alternate and reserve. About 5 hours into the flight, dispatch called to tell us that there should have been a third en route alternate and that we needed more fuel than we had for that alternate. We had to divert to anc for more fuel before proceeding on to sjc. Supplemental information from acn 469229: received call from dispatch informing us that we did not have sufficient fuel on board to cover the next leg of trip which was dispatched without a third equal time point. Upon closer scrutiny, dispatch realized that the ETOPS requirement for a third equal time point to comply with the 180 min rule had not been met. Fuel on board -- while more than adequate to reach destination -- was 3000 pounds less than necessary to provide for an additional en route alternate as required by the 180 min rule. No choice but to divert to comply with paper legality. Dispatch suggested divert to hnl, but anc was closer so diverted there. Better checks and balances in computer programming is necessary in the equal time point determination process. Some flight plans have not had any equal time points calculated. 2 equal time points are not unusual -- and that is why it was not caught by the flight crew.

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Original NASA ASRS Text

Title: ETOPS OP OVER THE PACIFIC DIVERTS WHEN DISPATCH DISCOVERS PLANNING FOR ENRTE ETOPS ALTERNATES WAS NOT CORRECT.

Narrative: MY FO MADE A COMMENT ABOUT ONLY 2 ENRTE ALTERNATES WHILE WORKING ON OUR FLT PLAN. I HAD SEEN THAT BEFORE AND DID NOT GIVE IT MUCH CONSIDERATION. WE HAD ADEQUATE FUEL FOR THE TRIP -- ALTERNATE AND RESERVE. ABOUT 5 HRS INTO THE FLT, DISPATCH CALLED TO TELL US THAT THERE SHOULD HAVE BEEN A THIRD ENRTE ALTERNATE AND THAT WE NEEDED MORE FUEL THAN WE HAD FOR THAT ALTERNATE. WE HAD TO DIVERT TO ANC FOR MORE FUEL BEFORE PROCEEDING ON TO SJC. SUPPLEMENTAL INFO FROM ACN 469229: RECEIVED CALL FROM DISPATCH INFORMING US THAT WE DID NOT HAVE SUFFICIENT FUEL ON BOARD TO COVER THE NEXT LEG OF TRIP WHICH WAS DISPATCHED WITHOUT A THIRD EQUAL TIME POINT. UPON CLOSER SCRUTINY, DISPATCH REALIZED THAT THE ETOPS REQUIREMENT FOR A THIRD EQUAL TIME POINT TO COMPLY WITH THE 180 MIN RULE HAD NOT BEEN MET. FUEL ON BOARD -- WHILE MORE THAN ADEQUATE TO REACH DEST -- WAS 3000 LBS LESS THAN NECESSARY TO PROVIDE FOR AN ADDITIONAL ENRTE ALTERNATE AS REQUIRED BY THE 180 MIN RULE. NO CHOICE BUT TO DIVERT TO COMPLY WITH PAPER LEGALITY. DISPATCH SUGGESTED DIVERT TO HNL, BUT ANC WAS CLOSER SO DIVERTED THERE. BETTER CHKS AND BALS IN COMPUTER PROGRAMMING IS NECESSARY IN THE EQUAL TIME POINT DETERMINATION PROCESS. SOME FLT PLANS HAVE NOT HAD ANY EQUAL TIME POINTS CALCULATED. 2 EQUAL TIME POINTS ARE NOT UNUSUAL -- AND THAT IS WHY IT WAS NOT CAUGHT BY THE FLC.

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.