B767 Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine
Flight Crew Last 90 Days 166; Flight Crew Total 16947; Flight Crew Type 4871
Situational Awareness; Communication Breakdown; Time Pressure
Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued New Clearance; Flight Crew Took Evasive Action; Flight Crew Requested ATC Assistance / Clarification
Human Factors; Weather
We were issued SIGMET B01 from Iceland Radio (IR) on VHF and contacted Dispatch to get their advice since they had not given a heads up. A reply said we should not expect turbulence other than light. Then they sent a report of turbulence along the coast line of Greenland. Then they sent a new SIGMET B02 which implied the SIGMET was now a concern. To play it safe; we decided to request a route change to try to avoid severe TURB/MTN wave associated with SIGMET B02. We were moments away from N66W030 and needed to turn right approximately 45 degrees to avoid the area of concern; so we started to use CPDLC to make a request 'PP to N6730W030; then flight plan route'; but realized it would take a lot of typing to explain and send it. The First Officer picked up the mike and asked Iceland Radio to get the clearance. Then we sent a similar/abbreviated CPDLC request. Iceland Radio gave us the clearance and we made the turn. CPDLC asked when we could accept FL350. A lot was going on right then with FMC changes; so I quickly sent a CPDLC request to climb to FL350; thinking that the new altitude may be important to BIRD. A clearance came back to climb; report leaving; and report level. The First Officer told Iceland Radio (IR) we were departing FL340 for FL350; yet IR probably had no idea we had been cleared. We reported when level on the radio. Meanwhile the original CPDLC request for our 'time' to accept a climb was still open and the clearance to climb/report was still open. We had a difficult time trying to clear both at this point since the normal response flow was out of sequence. Iceland Radio eventually told us we had CPDLC failure and instructed us to NOT log in to BIRD again. We complied by using only voice until out of BIRD airspace; eventually using CPDLC again with Edmonton. The two methods of communication used; due to the seemingly urgent need to avoid the 'severe' and still comply with the actual clearances; became too complicated and confusing. I am confident we had both the route and altitude clearances prior to making the changes; yet I am sure that it was just as confusing on the other end for ATC. As captain; I need to ensure only one means of communication is primary. I should have waited on the altitude request until the current workload was complete.
B767 Captain is informed of sever turbulence ahead during a North Atlantic crossing while in VHF contact with BIRD and logged on with BIRD CPDLC. A deviation is requested using both VHF and CPDLC which results in confusion for both ATC and the flight crew.