Narrative:

Enroute to coast-out was extremely busy. The initial fp had routing on/near the new york and gander oca's. After several queries as to who would issue our oceanic clearance; and several failed attempts at requesting clnc through ACARS; we were give a re-route to 45N/50W. Meanwhile dispatch was suggesting a re-route north of an area of turbulence and weather that would have us entering the tracks at 47 or 48 north latitude. Gander domestic received that route and issued it verbally - ronpo 4750 4740 4830 as filed. I went direct ronpo and began editing the new route in the FMC. I typed N4750 N4740 N4830 and then closed the route after 20W. This added 3 minutes to our FMC prog page arrival time. We were cleared direct 4750 shortly later. I then queried dispatch about ETOPS altns and etp's. He said the RLS2 fp ETOPS altn's were still good; which was the previous re-route sent to us in flight. I entered them on Route2 and they looked proper as well i.e.; - they were near; but not exactly on the cleared route. This was expected since I didn't yet have the new fp (with exact etp's - RLS3). The printer later began printing RLS3; but did not finish until minutes before crossing N4750. I immediately began performing an ETOPS waypoint verification. The relief pilot had just come back from break. I pointed out to him that the bearing and distances from 50W to 40W and 40W to 30W were off by 6-7 degrees and 5 miles - showing 406NM vice 411 NM. Typically I see these match within 2-3 degrees and 0-2 NM. Also of note looking back on the event; I was unable to upload new winds. We received an ACARS error message after sending an FMC wind request. Both of these occurred within minutes of crossing 50W. Radar service was terminated 5 minutes prior to crossing N4750. We had been proceeding direct to that point for about 30 minutes. Immediately after crossing 50W; we were called by gander oceanic [and informed] that we were 30 NM north of course. They directed us to turn 30 degrees right to re-join our route. The said they could see all our points on the crossing were 30 NM north of the cleared route. As everything looked proper on the FMC legs and nd I then checked the position init page and saw our position in the vicinity of 47.5N latitude; one half degree or 30 NM to the north. Gander issued further clarity that the waypoints must be typed incorrectly and check that the 'north' is trailing the lat/long vice leading. Specifically; 47n50w should be entered as 4750N vice N4750. I typed all the new points in with a leading 'north.' incredibly; a very recent database change accepts this as 47.5N/50W. We returned to course uneventfully thereafter. I typed the waypoints incorrectly with a leading 'north;' and despite independent verification with the captain; it was not discovered.

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Original NASA ASRS Text

Title: B767 flight crew reports a navigational error entering the NATS at 47N50W after a reroute is issued by Gander. The three new waypoints required are entered with a leading 'N' instead of a trailing 'N' producing a waypoint that is accepted by the FMC but a half a degree north of the desired latitude. This error is detected by Gander and the cause is known.

Narrative: Enroute to coast-out was extremely busy. The initial FP had routing on/near the New York and Gander OCA's. After several queries as to who would issue our Oceanic Clearance; and several failed attempts at requesting CLNC through ACARS; we were give a re-route to 45N/50W. Meanwhile Dispatch was suggesting a re-route north of an area of turbulence and weather that would have us entering the tracks at 47 or 48 North latitude. Gander Domestic received that route and issued it verbally - RONPO 4750 4740 4830 as filed. I went direct RONPO and began editing the new route in the FMC. I typed N4750 N4740 N4830 and then closed the route after 20W. This added 3 minutes to our FMC PROG page arrival time. We were cleared direct 4750 shortly later. I then queried dispatch about ETOPS ALTNS and ETP's. He said the RLS2 FP ETOPS ALTN's were still good; which was the previous re-route sent to us in flight. I entered them on Route2 and they looked proper as well i.e.; - they were near; but not exactly on the cleared route. This was expected since I didn't yet have the new FP (with exact ETP's - RLS3). The printer later began printing RLS3; but did not finish until minutes before crossing N4750. I immediately began performing an ETOPS waypoint verification. The Relief Pilot had just come back from break. I pointed out to him that the bearing and distances from 50W to 40W and 40W to 30W were off by 6-7 degrees and 5 miles - showing 406NM vice 411 NM. Typically I see these match within 2-3 degrees and 0-2 NM. Also of note looking back on the event; I was unable to upload new winds. We received an ACARS error message after sending an FMC wind request. Both of these occurred within minutes of crossing 50W. Radar service was terminated 5 minutes prior to crossing N4750. We had been proceeding direct to that point for about 30 minutes. Immediately after crossing 50W; we were called by Gander Oceanic [and informed] that we were 30 NM north of course. They directed us to turn 30 degrees right to re-join our route. The said they could see all our points on the crossing were 30 NM north of the cleared route. As everything looked proper on the FMC legs and ND I then checked the POS init page and saw our position in the vicinity of 47.5N latitude; one half degree or 30 NM to the North. Gander issued further clarity that the waypoints must be typed incorrectly and check that the 'N' is trailing the lat/long vice leading. Specifically; 47N50W should be entered as 4750N vice N4750. I typed all the new points in with a leading 'N.' Incredibly; a very recent database change accepts this as 47.5N/50W. We returned to course uneventfully thereafter. I typed the waypoints incorrectly with a leading 'N;' and despite independent verification with the Captain; it was not discovered.

Data retrieved from NASA's ASRS site 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.