Narrative:

Normal crew is 2 pilots and 1 flight attendant. We launched as an augmented crew (3 pilots) to conform with dispatch requirements for extended duty hours. This particular flight would require approximately 17.5 block hours beginning the afternoon of jul/xx/94. En route on the 1ST leg, subsequently rtes were entered into the FMS's by the relief air crew. Several waypoints required manual entry of LA9/long positions. The 3RD and final leg was extended, overwater routing which I elected to fly. Upon receipt of our clearance, we verified the routing as correct in the active plan of the FMS. En route though our time an distance to 42no40w did not match the computer plan. New york arinc also asked us to repeat our time and to also report our time over 045W. It was then I discovered that waypoint 3950 was named correctly but entered with the wrong coordinates. We were off course but correcting to 42n040w. Classic error! I assumed the flight plan, as entered previously was correct. (Only the designators were one set of coordinates was wrong.) we are reviewing augmented crew requirements. The impact of fatigue and crew coordination must be stressed; the need for accuracy in data loading via a 'challenge -- respond' method is policy. Nothing is assumed. Supplemental information from acn 277423: we flew to mexico city to pick up our passenger. The writer was in the left seat for this leg and during the flight I inserted the next 2 legs of the flight into the flight management system, which was mexico city to bermuda and bermuda to madrid. Until recently the system software allowed overwater latitude/longitude to ben entered as, for instance, 3950 north for 39 degrees north/50 degrees west. A recent software update removed that capability and required that the entire north 3900.0/W5000.0 be typed into the flight plan. I typed in the various latitude/longitudes for the overwater phase identing each waypoint in the previous manner, eg, 3560N, 3950N, 4240N, etc. In actually typing in the latitude/longitudes, I erroneously typed in 35 degrees north latitude at 50 west longitude, instead of 39 degrees north latitude at 50 west longitude. After refueling in bermuda at about am local I came from a crew rest station and took the right seat for the leg from bermuda to madrid. The flight plan was called up and displayed. A deviation in the path was noted, but was not considered unusual. The waypoints had been previously double checked, but since the legend assigned was 3950 north it was assumed it represented the correct latitude/longitude. During the flight new york arinc questioned our estimate for 4240 north and subsequently asked for our estimate at 45 degrees west. Crew fatigue was a definite factor. Neither pilot noted any problem until the second new york call, even though present position was read out continuously. I doubt if there was another airplane within 500 mi at our altitude. Our TCASII never showed anything.

Google
 

Original NASA ASRS Text

Title: ACFT HAS LARGE NAVIGATIONAL ERROR AS IT FLIES ACROSS THE ATLANTIC. ERROR IS CAUSED BY WRONG INSERTION OF LATITUDE AND LONGITUDE COORDINATES INTO FLT MGMNT COMPUTER.

Narrative: NORMAL CREW IS 2 PLTS AND 1 FLT ATTENDANT. WE LAUNCHED AS AN AUGMENTED CREW (3 PLTS) TO CONFORM WITH DISPATCH REQUIREMENTS FOR EXTENDED DUTY HRS. THIS PARTICULAR FLT WOULD REQUIRE APPROX 17.5 BLOCK HRS BEGINNING THE AFTERNOON OF JUL/XX/94. ENRTE ON THE 1ST LEG, SUBSEQUENTLY RTES WERE ENTERED INTO THE FMS'S BY THE RELIEF AIR CREW. SEVERAL WAYPOINTS REQUIRED MANUAL ENTRY OF LA9/LONG POSITIONS. THE 3RD AND FINAL LEG WAS EXTENDED, OVERWATER ROUTING WHICH I ELECTED TO FLY. UPON RECEIPT OF OUR CLRNC, WE VERIFIED THE ROUTING AS CORRECT IN THE ACTIVE PLAN OF THE FMS. ENRTE THOUGH OUR TIME AN DISTANCE TO 42NO40W DID NOT MATCH THE COMPUTER PLAN. NEW YORK ARINC ALSO ASKED US TO REPEAT OUR TIME AND TO ALSO RPT OUR TIME OVER 045W. IT WAS THEN I DISCOVERED THAT WAYPOINT 3950 WAS NAMED CORRECTLY BUT ENTERED WITH THE WRONG COORDINATES. WE WERE OFF COURSE BUT CORRECTING TO 42N040W. CLASSIC ERROR! I ASSUMED THE FLT PLAN, AS ENTERED PREVIOUSLY WAS CORRECT. (ONLY THE DESIGNATORS WERE ONE SET OF COORDINATES WAS WRONG.) WE ARE REVIEWING AUGMENTED CREW REQUIREMENTS. THE IMPACT OF FATIGUE AND CREW COORD MUST BE STRESSED; THE NEED FOR ACCURACY IN DATA LOADING VIA A 'CHALLENGE -- RESPOND' METHOD IS POLICY. NOTHING IS ASSUMED. SUPPLEMENTAL INFO FROM ACN 277423: WE FLEW TO MEXICO CITY TO PICK UP OUR PAX. THE WRITER WAS IN THE L SEAT FOR THIS LEG AND DURING THE FLT I INSERTED THE NEXT 2 LEGS OF THE FLT INTO THE FLT MGMNT SYS, WHICH WAS MEXICO CITY TO BERMUDA AND BERMUDA TO MADRID. UNTIL RECENTLY THE SYS SOFTWARE ALLOWED OVERWATER LATITUDE/LONGITUDE TO BEN ENTERED AS, FOR INSTANCE, 3950 N FOR 39 DEGS N/50 DEGS W. A RECENT SOFTWARE UPDATE REMOVED THAT CAPABILITY AND REQUIRED THAT THE ENTIRE N 3900.0/W5000.0 BE TYPED INTO THE FLT PLAN. I TYPED IN THE VARIOUS LATITUDE/LONGITUDES FOR THE OVERWATER PHASE IDENTING EACH WAYPOINT IN THE PREVIOUS MANNER, EG, 3560N, 3950N, 4240N, ETC. IN ACTUALLY TYPING IN THE LATITUDE/LONGITUDES, I ERRONEOUSLY TYPED IN 35 DEGS N LATITUDE AT 50 W LONGITUDE, INSTEAD OF 39 DEGS N LATITUDE AT 50 W LONGITUDE. AFTER REFUELING IN BERMUDA AT ABOUT AM LCL I CAME FROM A CREW REST STATION AND TOOK THE R SEAT FOR THE LEG FROM BERMUDA TO MADRID. THE FLT PLAN WAS CALLED UP AND DISPLAYED. A DEV IN THE PATH WAS NOTED, BUT WAS NOT CONSIDERED UNUSUAL. THE WAYPOINTS HAD BEEN PREVIOUSLY DOUBLE CHKED, BUT SINCE THE LEGEND ASSIGNED WAS 3950 N IT WAS ASSUMED IT REPRESENTED THE CORRECT LATITUDE/LONGITUDE. DURING THE FLT NEW YORK ARINC QUESTIONED OUR ESTIMATE FOR 4240 N AND SUBSEQUENTLY ASKED FOR OUR ESTIMATE AT 45 DEGS W. CREW FATIGUE WAS A DEFINITE FACTOR. NEITHER PLT NOTED ANY PROB UNTIL THE SECOND NEW YORK CALL, EVEN THOUGH PRESENT POS WAS READ OUT CONTINUOUSLY. I DOUBT IF THERE WAS ANOTHER AIRPLANE WITHIN 500 MI AT OUR ALT. OUR TCASII NEVER SHOWED ANYTHING.

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.