B757 Undifferentiated or Other Model
Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Flight Crew Total 1028; Flight Crew Type 940
Communication Breakdown
Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter Weather / Turbulence
Flight Crew Requested ATC Assistance / Clarification
Weather; Procedure; Aircraft
As we were traveling west and checked in with New York. we decided we needed to deviate for weather. Since we had just checked in with ZWY; we opted for voice rather than CPDLC for convenience. We were about 60 miles away at that time. The controller replied to stand by. After 5-10 minutes (about 30 miles from weather) went on without a reply; we called again to verify our request. ZWY wondered if we had received a CPDLC message; and we replied we had not. They said to standby. About 20 NM from the storm; we told ZWY we needed to deviate now; and that we were to deviate 10 NM south as requested. ZWY said they would relay. We gave an all traffic call advising about the deviation. The deviation started at about XA30 and ended about XA42. We reported back on track with ZWY and to general traffic. At this time ATC inquired about the logon status of our CPDLC uplink. We looked and realized the box was still linked with CZQX; having not yet switched after crossing [fix]. We told ATC and they said that was why we had not received any CPDLC message. We acknowledged that which ended the transmission. That's when we had a discussion about if we had had a clearance or not; that maybe we had been cleared through CPDLC but not received the message thanks to the late login transfer. We queried ATC which sent back a CPDLC message explaining that they had been working on it; but it had not been issued; so a possible pilot deviation existed.
757 flight crew reported deviating without ATC clearance due to weather and miscommunication.