B737 Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 362
Other / Unknown; Time Pressure; Distraction; Communication Breakdown
Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Became Reoriented
Environment - Non Weather Related; Human Factors
We were about to takeoff on 28; and Dispatch advised us to return to the gate due to a power outage [at destination]. We returned to a gate in BWI; shut one engine down; but waited at least 30 minutes for a Ground Crew to park us. After about 35 minutes; Dispatch advised us that [destination] was open again. We were still waiting to be parked; so we amended our Release for the fuel we burned; ran the numbers for our lighter weight; ran the Before Push and Before Taxi Checklists; and taxied back to Runway 28 for departure. During the initial climb; I noticed that we had departed without arming the autobrakes.We should have run the Before Start Checklist before we restarted the number 2 engine again; due to the fact that we did the after landing flow while we were taxiing back to the gate.
B737 Captain reported taking off without arming the autobrakes.