Date: 201908
Local time of day: 1801-2400
Location: ATL.Airport, GA
Light: Daylight
Aircraft: B737-700
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Takeoff / Launch
Airspace: Class B ATL
ATC / advisory: Tower ATL
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Human factors: Communication Breakdown; Distraction; Time Pressure
Anomaly: Conflict Ground Conflict; Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Regained Aircraft Control; Flight Crew Rejected Takeoff
Contributing factors: Human Factors; Procedure
Primary problem: Procedure

Narrative: Flight XXXX had been sitting at the gate due to an EDCT (Estimated Departure Clearance Time) related to weather on the east coast. I called the Dispatcher; and he recommended boarding the flight while he called Traffic Management Unit (TMU). We taxied out to prepare for a Runway 9R Departure; intersection M2. As we got in line; ATC advised us we had approximately 45 more minutes before our EDCT. I asked the FO (First Officer) to inquire Ground Control for a spot where we can shut down both engines. We figured that there may be some deviations for weather and possible holding for flow. ATC placed us behind an (other carrier) aircraft on Taxiway Lima; facing opposite the flow of traffic headed from the gates to Runway 9R/M2 intersection.I pulled in close. It became apparent that the CRJ was running up his engines in order to burn fuel; probably to be within his takeoff weight limits. Because we were so close; the thrust from the engines of the CRJ was causing our aircraft to buffet in the jet blast. I discussed this with my FO. I also mentioned my concern that the high thrust setting might create lift over our wings; and extended the spoilers as a preemptive measure. The thrust was strong enough to cause airspeed fluctuations and a continuous; gentle buffeting of our airframe. After 20 minutes; the CRJ was cleared for takeoff; followed by us. We completed the start-up and performed the Before Takeoff Checklist. On the runway; the FO set the power and commanded 'SET TAKEOFF THRUST'. As the thrust levers advanced; the Takeoff Configuration Warning Horn sounded. I disconnected the Autothrottle and pulled both throttles to idle. We had accelerated to less than 20 kts. I asked the FO to inform ATC that we were aborting the takeoff and to request rejoining the line. ATC asked us 'What is the reason for your abortion?' We found that quite humorous; and we told them 'Takeoff Configuration Warning'. I declined any assistance; and rechecked flaps; slats; and exercised the spoiler handle. We ran the Before Takeoff Checklist again; and I repeated the Before Takeoff Flow (Throttle 'burst'; Autothrottle ON; FA (Flight Attendant) 'DING'). After another 12 minute delay for takeoff sequencing; we had an uneventful departure from ATL.




Synopsis: B737-700 Captain reported that during ground hold; the spoilers were extended and were never reset prior to take off roll; resulting in a rejected takeoff.