Date: 201909
Local time of day: 1801-2400
Location: ZNY.ARTCC, NY
Flight conditions: VMC
Light: Night
Aircraft: Gulfstream G650
Operator: Corporate
Operating under: Part 91
Flight plan: IFR
Mission: Passenger
Flight phase: Cruise
Airspace: Class A ZNY
ATC / advisory: Center ZNY
Reporter organization: Corporate
Reporter function: Captain; Pilot Not Flying; Relief Pilot
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Flight Instructor; Flight Crew Multiengine; Flight Crew Instrument
Human factors: Communication Breakdown; Confusion; Situational Awareness
Anomaly: Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Flight Crew Requested ATC Assistance / Clarification
Contributing factors: Airspace Structure; Chart Or Publication; Procedure; Human Factors
Primary problem: Human Factors

Narrative: Our aircraft received oceanic clearance from Santa Maria well before coast out. The oceanic clearance also matched our filed flight plan with the following route clearance. Before oceanic entry we were given a revised altitude to maintain FL410. After entering Santa Maria Oceanic airspace; we were cleared to point 42N040W; the boundary with New York Oceanic. At this point; I was due for a scheduled rest period as we were an augmented crew on an 18-hour duty day. After slightly over two hours sleep; I returned to the cockpit and plugged into the observer seat audio panel with my headset. We were currently on the cleared routing; about 150 miles east of 43N050W; when a message via CPDLC from New York oceanic came through questioning why our ADS kept reporting 43N060W as our next waypoint after 43N050W. 43N060W was not in our FMS waypoint list. However; after consulting the plotting chart; we figured out that lat/long was the position for a point on our initial oceanic clearance.After back and forth with Center we were told after 43N050W to proceed direct 42N060W [then en route] to our destination. Center said this was to avoid active military airspace. The flying crew stated this was the first time they were seeing this new clearance. Center did not initially send a new routing via CPDLC uplink so I requested the crew contact New York radio via HF as well to clarify the routing and confirm the 're-clearance.' New York responded with a CPDLC routing that we could apply and activate. We then flew the ATC issued new routing and did not deviate from the oceanic clearance. At this point; it was time for the First Officer; the flying pilot; to take his scheduled rest period. The third pilot; a Captain qualified contractor; already had the first scheduled rest period. When I sat down at the crewmember station; I looked at the CPDLC log of messages that arrived while I was sleeping in the crew rest compartment. I noticed a message that said 'At 43N050W; Cleared Route Clearance' that was replied with a 'WILCO' from the flying crew. I went to the second page of the message and clicked on the 'ATC CLNC' prompt and it showed a clearance was given to the flying crew stating that after 43N050W; they were to proceed on the above route that Center was expecting the aircraft to fly. The crew flying when the message arrived told me they thought this was the standard 'Confirm Assigned Route' message that generates when you enter a new oceanic sector. A re-clearance as such requires additional searching on the CPDLC menu to find the route; as it is located in a sub-menu and not very apparent. Either way; the flying crew did accept the new clearance unknowingly thinking they were just confirming the assigned route and kept the original oceanic routing in the FMS. After I discovered the error made by the flying crew; I briefed the pilot contractor and later briefed the first officer after landing. Thankfully; the system works as it is intended to; with ADS reporting next and ensuing waypoints and ATC confirming that the waypoints match the cleared route. Center Oceanic intervened well before a navigation error could have occurred. After discussion; more attention to a CPDLC message that would have said 'RE-CLEARANCE' versus 'At 43N050W Cleared Route Clearance' would have gotten the cockpit crews attention that something on the route needed to be changed in the FMS. In addition; the Honeywell system to show a new clearance is not the most user friendly as it requires you to go into a submenu to view the actual new clearance. These issues combined with a crew experiencing a max duty day; and a pilot contractor on his first trip with the department; lead to an error that could have resulted in a navigation error if not for Center checking our ensuing flightplan waypoints reported via ADS. The aircraft continued on with no issues and landed safely at our destination. This is a good learning opportunity for the entire pilot group. Therefore; this report will be posted to our flight department's internal SMS program so it can be discussed by the safety committee and presented to all department members for open discussion; seeking ideas to prevent a future occurrence. I personally will suggest that when attending the next G650 recurrent over the next two months; all crewmembers repeat the interactive tutorial on G650 CPDLC use and phraseology; with all pertinent scenario's that is provided by our training provider. As well; I will stress the importance of fully understanding a CPDLC message before sending a 'WILCO' response. If the crew had printed that message; the full routing would have appeared. Therefore; I will suggest that any message with the word 'clearance' in should be printed and analyzed.




Synopsis: G650 pilot reported the crew did not clarify a route message received via CPDLC and the crew had an error in their programmed oceanic route.