Date: 202011
Location: CZQX.ARTCC, NF
Aircraft: Medium Large Transport; Low Wing; 2 Turbojet Eng
Operator: Air Taxi
Operating under: Part 135
Flight plan: IFR
Mission: Passenger
Flight phase: Cruise
Airspace: Class A CZQX
ATC / advisory: Center CZQX
Reporter organization: Air Taxi
Reporter function: Pilot Not Flying; Captain
Reporter qualification: Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Human factors: Communication Breakdown; Confusion
Anomaly: ATC Issue All Types; Deviation - Speed All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural FAR
Detector: Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Flight Crew Requested ATC Assistance / Clarification
Contributing factors: Manuals; Procedure
Primary problem: Procedure

Narrative: We were navigating between coordinates at FL410 and M.80 assigned.  We received a CPDLC clearance that said; 'Resume normal speed'.  We reviewed the Europe Jeppesen Airway Manual section entitled 'Operations Without an Assigned Speed' to review this relatively new procedure. After agreeing on what it meant we accelerated to M.83 and advised ATC at XA:03z via CPDLC 'Present speed .83'.  ATC responded at XA:13z with 'Do you want M.83'.  We responded; 'Received normal speed CLNC and advising our speed is .83'.  At XA:17z ATC sent; 'You may want to read up on that. Resume normal speed means plus or minus mach .01 from cleared mach.'  We immediately changed speed to Mach .81 and replied; 'Roger speed now is .81 requesting M.83' (XA:18z). At XA:19z ATC sent 'Maintain .83M'. All communications were done via CPDLC. The rest of the flight was uneventful.  We disagree with the controller's interpretation of the 'Resume normal speed' clearance and request clarification from the company. Page 668 of the Jeppesen Airway Manual (Europe) says; 'If the aircraft then receives RESUME NORMAL SPEED (via CPDLC or Voice); the flight crew no longer needs to comply with a previously issued Mach. However; the flight crew shall advise ATC if; as the result of the RESUME NORMAL SPEED message; they intend to adjust their speed by plus or minus Mach 0.02 or more from their last assigned speed.'  Furthermore; in the operational example given on page 688 it says; '...message RESUME NORMAL SPEED will be sent.  The flight crew no longer needs to comply with a previously issued Mach. However; the flight crew shall advise ATC if; as the result of the RESUME NORMAL SPEED message; they intend to adjust their speed by plus or minus Mach 0.02 or more from their last assigned speed. In this case; with a previously assigned speed of .81; they must inform ATC if the flight either slows to M.79 or less or speeds up to M.83 or more.'  Finally; in the North America Jeppesen Airway Manual it says; ' When adherence to an assigned 'MACH' setting is no longer required; pilots will receive a controller-pilot data link communications (CPDLC) message to 'RESUME NORMAL SPEED;' at which point the flight crew can continue at their cost index. Refer to aeronautical information circular (AIC) 1/20 Operations Without an Assigned Fixed Speed (OWAFS) in the North Atlantic for more details.'  In looking at the ICAO NAT OPS Bulletin (2019_001); the text mimics what is published in the Jeppesen Airway Manual. In conclusion; I believe we were in full compliance with the 'Resume normal speed' clearance when we accelerated to M.83 and advised ATC but since the controller has a different understanding of the situation I would like to get clarification from the company.




Synopsis: Medium Large Transport Captain received CPDLC speed clearance from Gander Control which created procedural confusion between ATC; Jeppesen manual; and company policy.