B767 Undifferentiated or Other Model
Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Training / Qualification; Situational Awareness; Communication Breakdown
Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Became Reoriented
Human Factors
At altitude several hours into an uneventful flight I elected to transfer control of the aircraft to the First Officer and exit the cockpit to retrieve my meal from the galley. Upon reentry attempt I entered the security code for the cockpit door. I witnessed the appropriate lights illuminated and heard the chime from the other side of the door. I was; I assume mistakenly; denied access by the First Officer. I waited a moment or two for him to realize his error and turn the control knob to unlock; thus granting me access despite the original selection. This did not happen. I reentered the security code from outside the cockpit door. But; because of my previous deny status the door was in a reset mode and no chime or indication of my second entry request was received inside the cockpit. I could have elected to stand outside the door for several minutes for the timer to count down allowing me a re-attempt; but; because I did not know what was going on inside the cockpit I elected to call the First Officer on the provided intercom system. I could hear the intercom chime through the door. He did not answer. I called the second time. He did not answer. I called a third time. At this point; because he did not know how to operate the door unlock system and not know how to operate the intercom; the First Officer elected to get up from his seat to manually open the door for me.
B767 Captain reported being locked out of the cockpit and the FO not knowing how to unlock the door to let him back in.