Flight Crew Air Transport Pilot (ATP)
Communication Breakdown
Conflict Ground Conflict; Critical; Ground Incursion Runway
Flight Crew Rejected Takeoff
Human Factors; Procedure
We were instructed to line up and wait with traffic to cross down field on Runway 27R. Tower instructed a host of aircraft to cross the runway. After all of the aircraft had crossed; Tower then cleared us for takeoff. I was PM; the Captain was PF. Around 80 knots I saw a Air Carrier Y edging out onto the runway and [I] verbalized this to the Captain. Tower then said something like 'Air Carrier Y; what are you doing? Stop right there.' This; coupled with the fact that the Air Carrier Y continued moving out onto the runway was enough reason for the Captain to call a rejected takeoff (now at around 100 knots). Tower did not instruct us to abort. We safely came to a stop and exited the runway and completed the QRH and appropriate checklists. It seemed as though Tower assumed Air Carrier Y had crossed when we had been cleared for takeoff; but they had actually not even begun to cross the runway. Additionally; it's tough to see Taxiway Papa (where Air Carrier Y) while you're at the approach end of 27R. Regardless; we shouldn't have been cleared to take off or Air Carrier Y's clearance to cross the runway should have been cancelled. I do not know what happened in the Tower; but we stopped as soon as we saw it was unsafe to continue.
We were cleared to lineup and wait on 27R in Atlanta while several aircraft were cleared to cross down field. When the runway was clear; we were given a takeoff clearance by tower. (We saw no aircraft on the runway when we received the takeoff clearance.) As we passed through 80 knots; my FO/PM brought to my attention that Air Carrier Y was crossing the runway. It took me a moment to process that we had a runway incursion. I initiated a rejected takeoff at about 100 knots. My FO informed tower of our abort; and we exited the runway on the highspeed Taxiway M12. I made a PA to inform the passengers that we discontinued the takeoff due to something on the runway; to stay seated with their seatbelts fastened; and that we would go back for takeoff shortly. We completed the RTO and after landing checklists and contacted dispatch. I checked with the FA; and all crew members were good to continue. We continued the flight with no further interruptions.We thought that Air Carrier Y mistakenly crossed 27R at P without a clearance after we were given the takeoff clearance. However; it appears that ATL Tower had cleared Air Carrier Y to cross 27R along with several other aircraft while we were holding in position. About 60 seconds after Air Carrier Y was given the clearance to cross; we were given the Takeoff clearance. Neither Tower; nor we realized that there was an aircraft that had not crossed the runway yet.If Air Carrier Y was not ready to cross the runway; they should have informed Tower or not have accepted the runway crossing Clearance. They crossed the runway about 90 seconds after receiving the Clearance; and we were on the takeoff roll with all exterior lights on. Tower needed increased vigilance; and we as a flight crew could have been proactive by noticing that an aircraft had not crossed the runway yet.
Air carrier flight reported a rejected takeoff at about 100 knots at ATL airport due to a ground conflict with another air carrier crossing their runway.