PIC elects to abort takeoff as uneven engine spin up almost runs aircraft off runway.

Attributes
ACN	132927
Time
Date	198912
Day	Sun
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : lga
State Reference	NY
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	IMC
Light	Night
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other
Flight Phase	climbout : takeoff other
Route In Use	departure other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp pilot : cfi
Experience	flight time last 90 days : 172 flight time total : 8500 flight time type : 230
ASRS Report	132927
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time type : 60
Events
Anomaly	aircraft equipment problem : critical other anomaly other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : rejected takeoff
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation other other

Narrative:

We did not speak to the crew who brought our aircraft into lga as we arrived late from another flight. No write-ups or notes were found in the aircraft log book. We were cleared into position and hold on runway 31. After a landing aircraft arrived on 22, we were cleared for takeoff. Captain was PF (he had less than 100 hours in aircraft type as captain). Throttles were advanced to allow engines to stabilize at approximately 40% N1 (as is the procedure in the poh), then the autothrottle was engaged. Right engine accelerated normally. Left engine initially hesitated/'hung-up' where it was, at approximately 35-40% N1. As the right engine accelerated, aircraft started rolling forward and moving toward left side of runway centerline. I called out discrepancy I saw in N1 indications. While trying to return aircraft track to the centerline, captain further advanced left throttle in an attempt to match engine N1's, then brought both throttles to idle, electing to reject the takeoff. We then cleared the runway at a convenient taxiway, told the F/a's to remain seated and advised the tower of our intentions. Except for the left engine N1 being slow to accelerate (all other engine gauges appeared normal), we thought of no reason why not to try the takeoff again. We taxied back to the end of 31. Engine gauges matched normally during taxi. Captain and I did agree not to use the autothrottle this time, and make a static power takeoff. After completing the required checklists again, the tower cleared us for takeoff again on runway 31. Captain advanced the throttles to allow the engines to stabilize, then advanced them to takeoff power. Noting all engine gauges were matched normally, brakes were released and we took off. Climb to altitude and cruise were normal. During descent we discussed the possibility of getting asymmetrical reverse on landing. We landed 15 at btv and when reverse was applied, the left engine (as anticipated) initially hung up again (like on takeoff) between 35-40% N1. Aircraft was stopped west/O difficulty and we taxied to the gate. Captain then wrote up aircraft.

Original NASA ASRS Text

Title: PIC ELECTS TO ABORT TKOF AS UNEVEN ENGINE SPIN UP ALMOST RUNS ACFT OFF RWY.

Narrative: WE DID NOT SPEAK TO THE CREW WHO BROUGHT OUR ACFT INTO LGA AS WE ARRIVED LATE FROM ANOTHER FLT. NO WRITE-UPS OR NOTES WERE FOUND IN THE ACFT LOG BOOK. WE WERE CLRED INTO POS AND HOLD ON RWY 31. AFTER A LNDG ACFT ARRIVED ON 22, WE WERE CLRED FOR TKOF. CAPT WAS PF (HE HAD LESS THAN 100 HRS IN ACFT TYPE AS CAPT). THROTTLES WERE ADVANCED TO ALLOW ENGS TO STABILIZE AT APPROX 40% N1 (AS IS THE PROC IN THE POH), THEN THE AUTOTHROTTLE WAS ENGAGED. RIGHT ENG ACCELERATED NORMALLY. LEFT ENG INITIALLY HESITATED/'HUNG-UP' WHERE IT WAS, AT APPROX 35-40% N1. AS THE RIGHT ENG ACCELERATED, ACFT STARTED ROLLING FORWARD AND MOVING TOWARD LEFT SIDE OF RWY CENTERLINE. I CALLED OUT DISCREPANCY I SAW IN N1 INDICATIONS. WHILE TRYING TO RETURN ACFT TRACK TO THE CENTERLINE, CAPT FURTHER ADVANCED LEFT THROTTLE IN AN ATTEMPT TO MATCH ENG N1'S, THEN BROUGHT BOTH THROTTLES TO IDLE, ELECTING TO REJECT THE TKOF. WE THEN CLRED THE RWY AT A CONVENIENT TXWY, TOLD THE F/A'S TO REMAIN SEATED AND ADVISED THE TWR OF OUR INTENTIONS. EXCEPT FOR THE LEFT ENG N1 BEING SLOW TO ACCELERATE (ALL OTHER ENG GAUGES APPEARED NORMAL), WE THOUGHT OF NO REASON WHY NOT TO TRY THE TKOF AGAIN. WE TAXIED BACK TO THE END OF 31. ENG GAUGES MATCHED NORMALLY DURING TAXI. CAPT AND I DID AGREE NOT TO USE THE AUTOTHROTTLE THIS TIME, AND MAKE A STATIC PWR TKOF. AFTER COMPLETING THE REQUIRED CHKLISTS AGAIN, THE TWR CLRED US FOR TKOF AGAIN ON RWY 31. CAPT ADVANCED THE THROTTLES TO ALLOW THE ENGS TO STABILIZE, THEN ADVANCED THEM TO TKOF PWR. NOTING ALL ENG GAUGES WERE MATCHED NORMALLY, BRAKES WERE RELEASED AND WE TOOK OFF. CLB TO ALT AND CRUISE WERE NORMAL. DURING DSCNT WE DISCUSSED THE POSSIBILITY OF GETTING ASYMMETRICAL REVERSE ON LNDG. WE LANDED 15 AT BTV AND WHEN REVERSE WAS APPLIED, THE LEFT ENG (AS ANTICIPATED) INITIALLY HUNG UP AGAIN (LIKE ON TKOF) BTWN 35-40% N1. ACFT WAS STOPPED W/O DIFFICULTY AND WE TAXIED TO THE GATE. CAPT THEN WROTE UP ACFT.

Data retrieved from NASA's ASRS site as of August 2007 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.