Commercial Fixed Wing
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 12; Flight Crew Total 2071; Flight Crew Type 2071
Fatigue; Other / Unknown; Training / Qualification
Deviation / Discrepancy - Procedural Security; Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Other / Unknown
General None Reported / Taken
Human Factors; Environment - Non Weather Related
I was conducting an initial Operating Experience with a First Officer (FO) who is new to the aircraft. As we started our takeoff roll the Flight Deck door swung open. A Flight Attendant immediately closed the door and it was indicating locked. I was positive I checked the Flight Deck door 'OPEN' light during the After Start Checklist and it was out. I believe the door became unlocked during an electrical power transfer issue caused by me.When I called for the After Start Checklist; I was momentarily distracted while watching the FO perform his flows. I neglected to turn on the engine generators at the beginning of the flow. When the FO turned off the APU; we momentarily lost power (I immediately caught the mistake right when he was turning off the APU). I believe this may have electrically unlocked the door.Contributing factors: Not much sleep the night before.This was our first flight together.I flew 2 days last week after not flying for 6 months.It was right at dawn and I had the lights on dim just as the sun was starting to shine into the cockpit. I may have seen the blue Generator OFF BUS lights if the switch was on bright.
Air carrier Check Airman reported not following the published checklist due to fatigue and not having flown in the last 6 months.