Date: 201705
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Flight conditions: VMC
Light: Daylight
Aircraft: EMB ERJ 170/175 ER/LR
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Takeoff / Launch
ATC / advisory: Tower ZZZ
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Anomaly: Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: Taxi
Result: Flight Crew Rejected Takeoff
Contributing factors: Human Factors
Primary problem: Human Factors

Narrative: On this flight we were running behind schedule. We turned the aircraft in 29 [minutes]. I can say I don't feel as if we were rushing in any way. I was however concerned with my duty time at the end of our duty day. In my takeoff brief I briefed a 2 engine taxi as it was going to be a shorter taxi. We covered all aspects in the brief and completed all check lists prior to push back. The push back was uneventful; we were given clearance to start engines and to set brakes. I got the command to start engine one and a normal engine start was accomplished. After normal engine start I started my timer and called for flaps 2; APU off; Flight control check. We completed the task and ran the After Start Check List; and called for taxi. As I added power for taxi I noticed that I needed more thrust then I thought was needed; as if we were in a hole. The plane started moving and we taxied to the end if the Runway. As we approached the departure end of the Runway; I called for the before takeoff check list; the First Officer (FO) completed the tasks and read the checklist;' Takeoff OK'. We were cleared into position; and then cleared for TO. I pulled into position; full stop; armed the Auto throttles; and confirmed the heading; holding the brakes I advanced the throttles; call check thrust. It is at this point I recognized the right engine not running. Call reject; retarded the thrust levers and instructed the FO to inform tower of our aborted TO. We taxied clear; pulled in to the run up area preformed an engine start; reran the after start tasks and checklist; waited 2 minutes; ran the before takeoff checklist; called for TO. we were cleared for takeoff; I lined up on centerline armed AT; check heading; holding brakes advanced the TL's; called thrust and departed without any further incident.In this event I failed to recognize the fact that I was running on only one engine. We were operating about 2 hours behind schedule due to a maintenance issue at our previous departure airport. During the normal engine start I was somewhat preoccupied with a concern of our duty day. I feel this played a part in my failure. After the start of the #1 engine; The FO inquired as to why I start my timer. After short conversation; I called for the Flaps 2; APU off; Flight Control Check; tasks complete; After Start Check List; and Called for taxi.I can only think of these two factors during the engine start caused my failure to recognize the situation. As to the continued failure to recognize the situation; I will offer that it was a VFR day and we had a simple radar vector departure ahead of us; so I can say my own complacency is a contributing factor.As for suggestions to avoid this event. Continued situational awareness is the most important suggestion I have for myself. We are distracted every day and at all times by so many factors in our job. Maintaining a high level of situational awareness is important in bringing ones attention back to the tasks at hand. As for conversations which may concern operations of the flight; it is my responsibility to find the proper time to discuss these question; and to direct the attention of the flight crew back to the task at hand. eg. As is the practice of an interrupted checklist; start the checklist over. I also feel a debrief is necessary. A discussion into the factors of the event which lead the flight crew to fail in their duties. Also what each of the flight crew feel were their own contributing factors to the cause of the event. Finally as part of the debrief; what have we learned and how will we apply learning to our duties as flight crew.




Synopsis: ERJ170 Captain reported discovering the second engine had not been started while on the runway and beginning to advance the throttles for takeoff.