Date: 201905
Local time of day: 1801-2400
Location: MCO.Airport, FL
Light: Dusk
Aircraft: B737-800
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Initial Climb
Airspace: Class B MCO
ATC / advisory: TRACON F11
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Human factors: Situational Awareness
Second reporter function: Pilot Not Flying; First Officer
Anomaly: Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Air Traffic Control
When detected: In-flight
Result: Air Traffic Control Provided Assistance; Flight Crew Requested ATC Assistance / Clarification
Contributing factors: Human Factors
Primary problem: Human Factors

Narrative: After a 55 minute late arrival into MCO and an unscheduled aircraft swap; the FO (First Officer) and I shared duties of obtaining weather; CPDLC (Controller-Pilot Datalink Communications) and [Weight and Balance] data while the other pilot was attending to their own physiological needs in the terminal. As a result of the time pressure; we got rushed during the preflight so when I accomplished the required Pilot Flying briefing I had the expectation that the ATC route clearance had no changes; so I verbally briefed the route 'as filed' and failed to visual review the CPDLC a second time for any possible revisions. Then; during push and after engine start; we got distracted with a Master Caution annunciation for an Equipment Cooling Exhaust OFF light. I then had the F/O open the QRH and I cycled the Equipment Cooling Exhaust switch and the OFF light extinguished.During this distraction; a company aircraft waiting for our gate called and asked if we could move while accessing situation. We obliged and moved to a different spot on ramp. The condition was resolved so we continued for a normal taxi and takeoff. On a radar vector departure; ATC cleared us to JCT. When I looked at the FMC (Flight Management Computer) the JCT fix was not in our route of flight. No ATC deviation occurred. I immediately pulled up out CPDLC clearance and we both realized for the first time that we had received; missed and failed to load a revised ATC route clearance prior to takeoff. We then loaded the amended clearance and continued the flight without incident.


Second narrative: We were approximately one hour late arriving to MCO; leading to a late departure from MCO. I went to get food and then met the Captain at the new aircraft after a swap for our next leg. Arriving to the flight deck; the Captain informed me that the aircraft was set up and that he would be back shortly. I looked over the set up i.e. pressurization panel; FMC (Flight Management Computer); MCP (Mode Control Panel) etc. All seemed to be in order. The clearance had been issued via CPDLC and there was no ATC message needing acknowledgment on the display; so I thought the Captain had accepted the clearance. The Captain returned and we briefed as normal both agreeing to the clearance. After we had pushed off the gate I called for taxi; and Ground seemed unaware of us and asked for our squawk code. I furnished the code from the clearance and we continued. Just prior to taxiing we had an indication of a faulty exhaust fan; we ran the checklist and continued. Shortly after takeoff we were issued direct to a fix not on our flight plan. We queried ATC and they said it was on our route. At that point we went into the CPDLC log and found that there was an amended clearance that was ABORTED and never accepted. Essentially we had left on a revised route that we didn't accept; and may have had fuel issues if it wasn't addressed. We were given routing that met the fuel on board requirements and the flight was conducted without issue. Neither Dispatch; ATC; nor us realized that we had taken off on a revised but unacknowledged or accepted clearance.


Synopsis: B737-800 flight crew reported not acknowledging a revised clearance and being confused when given a fix not on the FMC by ATC.