Widebody; Low Wing; 2 Turbojet Eng
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 240; Flight Crew Total 29000; Flight Crew Type 10000
Troubleshooting; Fatigue; Confusion; Communication Breakdown; Human-Machine Interface
Aircraft Equipment Problem Less Severe; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Provided Assistance; Air Traffic Control Issued Advisory / Alert; Air Traffic Control Issued New Clearance; Flight Crew FLC complied w / Automation / Advisory; Flight Crew Became Reoriented; Flight Crew Returned To Clearance
Aircraft; Human Factors; Procedure; Chart Or Publication
We experienced a navigation deviation after reroute from track B to track A. I was not aware of Flight Manual (FM) change to use expanded waypoint construction and I used the abbreviated waypoint construction that was approved in the old Company FM. I incorrectly placed the N in the front of coordinates rather than at the end. The old FMC database would have rejected this coordinate as an 'invalid entry;' but obviously the new database does not; so we were actually flying to N5830 W02000; not N5800 W02000 after crossing SUNOT.At SUNOT; we followed Class waypoint navigation procedures; and all seemed normal. Shanwick Radio SELCAL'ed shortly after passing SUNOT and said our ADS reported us north of course. We verified our reroute and cross checked the Track A coordinates and verified LNAV engaged and on track. At that time we asked if they wanted us to turn off ADS; thinking it was reporting an erroneous position; and sent a CPDLC position report. A few minutes later Shanwick SELCAL'ed; requesting our current LAT/LONG; and we gave them real time coordinates. First Officer proactively plotted our position and confirmed that we were indeed north of course. Shanwick Radio requested we contact Shanwick ATC directly. I searched the index on SATCOM and found the new menu does not have a direct link address for ATC; only RADIO. Shanwick Radio provided the number for ATC. We don't have instructions in the FM for calling in this manner but we were able to figure it out and called Shanwick ATC directly. They were able to tell us through ADS that we had built a waypoint to N5830 by putting the N prior to the coordinates. I than used the expanded format N58 W030 and discovered our error. I advised them we were now going PP direct to N58 W030 and they acknowledged and then informed us this has happened a lot in the last few weeks and asked that we report this to the company. Of course we acknowledged and told them we would most certainly report.I've flown the North Atlantic for 20 years and have flown many a reroute with the abbreviated waypoint entry. The FMC was always a reliable check if the N was put in the front rather than the back. Obviously the new FM procedure using expanded construction is aware of this anomaly and thus the reason for new waypoint construction's lesson learned. The new Class 2 procedures were of little use but the plot that we recently abandoned was effective in verifying our position. SATCOM new menu just recently appeared and I can't find guidance in FM. Not being able to quickly select ATC facility is a step backwards and needs to be changed.
There are a number of issues that led to this error.Time compression when entering a last minute oceanic clearance with radio clarity issues led to a brief workload issue.The FMC accepting N5820; N5830; etc. placing it on the correct longitude at 30 minutes north of 58 degrees. The fact that all subsequent waypoints were placed 30 minutes north of course rendered the waypoint verification process useless. It wasn't until I started plotting did we discover the navigation error. There was no way to know that the waypoints were 30 minutes north unless you dug deep in the FMC. Everything in the FMC looked correct.As we approached our coast out fix we received at least two CPDLC downlink error messages which led us to believe we had an ADS/CPDLC problem and not a navigation problem.The new SABRE flight plan that was sent over the printer came over a long period of time that took us close to or even past the coast out fix; I don't recall the timing. In addition the flight plan pages did not come in order which made it particularly difficult to piece the flight plan back in its correct order.This entire episode seemed like a huge set up for a navigation error.As we approached our coast out fix we received at least two CPDLC down link error messages which led us to believe we had an ADS/CPDLC problem and not a navigation problem.The new SABRE flight plan that was sent over the printer came over a long period of time that took us close to or even past the coast out fix; I don't recall the timing. In addition the flight plan pages did not come in order which made it particularly difficult to piece the flight plan back in its correct order.
A wide body flight crew with CPDLC entered the NAT TRACK with coordinates formatted as N5830; N5840 and N5850 which caused ATC to notify the crew they were flying 30 minutes north of each waypoint. After lengthy discussions with ATC; 5830N; 5840N and 5850N were correctly entered.