Narrative:

Taxied out for takeoff single engine anticipating delays. After short delay started number 2 engine and completed the before takeoff checklist. Taxied into position when cleared using minimal thrust; about 35% max. When cleared to takeoff captain advanced thrust levers smoothly to the flex detent. Number 1 engine spooled up normally; number 2 lagged significantly behind number 1 reaching about 40% N1 when number 1 reached about 80% N1. Captain applied left rudder to compensate for differential thrust as aircraft accelerated slowly. Number 2 engine accelerated slowly from 40% to 55% over the next 3-4 seconds. Approximately 4 seconds after the thrust levers reached the flex detent with number 2 accelerating very slowly the captain elected to abort the takeoff due to insufficient thrust and no indication that the engine would resume a normal spool-up. Ground speed reached 45 KTS maximum; brakes were not applied as the first forward turnoff point was well down the runway. Exited the runway; taxied to a ground assigned spot to stop and call dispatch/maintenance. Local operations made several attempts to connect with dispatch. Crew was unable to hear dispatch despite operations being able to hear them. Captain called maintenance directly using personal cellphone. Advised maintenance engine controller of engine number 2 behavior and that the ECAM had not reported any faults. Maintenance directed a gate return. Taxied to gate with both engines running and noted that number 2 lagged significantly behind number 1 even at taxi thrust settings; a fact not noticed prior to takeoff attempt due to delayed engine number 2 start approaching end of runway.

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Original NASA ASRS Text

Title: An A319 flight crew reported they aborted their takeoff at low speed and returned to the gate when the number 2 engine failed to spool-up normally.

Narrative: Taxied out for takeoff single engine anticipating delays. After short delay started number 2 engine and completed the Before Takeoff Checklist. Taxied into position when cleared using minimal thrust; about 35% max. When cleared to takeoff Captain advanced thrust levers smoothly to the flex detent. Number 1 engine spooled up normally; number 2 lagged significantly behind number 1 reaching about 40% N1 when number 1 reached about 80% N1. Captain applied left rudder to compensate for differential thrust as aircraft accelerated slowly. Number 2 engine accelerated slowly from 40% to 55% over the next 3-4 seconds. Approximately 4 seconds after the thrust levers reached the flex detent with number 2 accelerating very slowly the Captain elected to abort the takeoff due to insufficient thrust and no indication that the engine would resume a normal spool-up. Ground speed reached 45 KTS maximum; brakes were not applied as the first forward turnoff point was well down the runway. Exited the runway; taxied to a ground assigned spot to stop and call Dispatch/Maintenance. Local operations made several attempts to connect with Dispatch. Crew was unable to hear Dispatch despite operations being able to hear them. Captain called maintenance directly using personal cellphone. Advised Maintenance Engine Controller of engine number 2 behavior and that the ECAM had not reported any faults. Maintenance directed a gate return. Taxied to gate with both engines running and noted that number 2 lagged significantly behind number 1 even at taxi thrust settings; a fact not noticed prior to takeoff attempt due to delayed engine number 2 start approaching end of runway.

Data retrieved from NASA's ASRS site as of April 2012 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.