Narrative:

We had four jumpseaters in addition to the three operating crew members. I left the cockpit to secure the cabin prior to push back. I started with shutting and arming door L1 and checked the rcb (rigid cargo barrier). I continued by inspecting the 4 cabin seats and proceeded to the right rcb. I then found bedding up against the supernumerary floor vents when I inspected them. I removed the bedding and the jumpseater placed the bedding alongside himself so it was properly secured. This is when I missed arming the R1 door. I went on to checking the galley compartments. When I arrived in the cockpit it occurred to me that I may have missed the R1 door so I checked the EICAS and saw 'doors auto' so I figured I had armed the door properly. When I returned to the supernumerary compartment later in the flight jumpseater next to the door called the error to my attention. I informed the captain and then armed the door.I believe that I made the error because of the numerous distractions that four jumpseaters on a long flight present. Stowing bags and bedding as well as maneuvering around extra bodies added a layer of complication. I lost track of where I was in my flow and missed arming the door. I needed to slow down and take as much time as was needed to complete the task at hand. I also misread the EICAS. I didn't finish reading it. It must have said doors auto/manual. I now have more familiarity with what the EICAS will say. I need to make sure that I take as much time as I need to be methodical in my tasks and take time to recheck things I am not certain about regardless if I feel like the crew is waiting on me to push.

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Original NASA ASRS Text

Title: B777 flight crew reported Relief Pilot did not arm the escape slide door prior to block-out.

Narrative: We had four jumpseaters in addition to the three operating crew members. I left the cockpit to secure the cabin prior to push back. I started with shutting and arming door L1 and checked the RCB (Rigid Cargo Barrier). I continued by inspecting the 4 cabin seats and proceeded to the right RCB. I then found bedding up against the supernumerary floor vents when I inspected them. I removed the bedding and the Jumpseater placed the bedding alongside himself so it was properly secured. This is when I missed arming the R1 door. I went on to checking the galley compartments. When I arrived in the cockpit it occurred to me that I may have missed the R1 door so I checked the EICAS and saw 'doors auto' so I figured I had armed the door properly. When I returned to the supernumerary compartment later in the flight jumpseater next to the door called the error to my attention. I informed the Captain and then armed the door.I believe that I made the error because of the numerous distractions that four jumpseaters on a long flight present. Stowing bags and bedding as well as maneuvering around extra bodies added a layer of complication. I lost track of where I was in my flow and missed arming the door. I needed to slow down and take as much time as was needed to complete the task at hand. I also misread the EICAS. I didn't finish reading it. It must have said doors auto/manual. I now have more familiarity with what the EICAS will say. I need to make sure that I take as much time as I need to be methodical in my tasks and take time to recheck things I am not certain about regardless if I feel like the crew is waiting on me to push.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.