Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 240; Flight Crew Total 8940; Flight Crew Type 1694
Aircraft Equipment Problem Less Severe
Air Traffic Control Provided Assistance; Flight Crew Rejected Takeoff; Flight Crew Returned To Gate; General Flight Cancelled / Delayed; General Maintenance Action
Aircraft
Normal operations until lining up [and] cleared for takeoff. As I was turning onto centerline I set throttles to 40%. An aircraft behind me called on Tower frequency and informed me there were flames coming out of back of left engine. I aborted takeoff at approximately 10 knots and taxied off [the runway] at first exit to right. We called emergency vehicles to meet us. Passengers were informed to stay seated. Vehicles arrived; noticed no abnormalities. No abnormal engine indications. We taxied back to gate.Additional comments:At no time were there any abnormal engine indications from either cockpit or from outside other than initial call from another aircraft that he saw flames in our exhaust. When asked we told Tower our Souls on Board and 2 hours of gas. I coordinated with emergency on radio 1 to observe our engines while we turned airplane around; and there were no abnormal visual indications. After discussion with maintenance; we decided to taxi back to gate by our own power. Wrote up in log book and interview two passengers who saw the event.
B737 Captain reported rejecting the takeoff when another aircraft reported seeing flames from the left engine.