Service difficulty report · Unknown · Boeing 737890

Difficulty date
February 22, 2019
Submitted
February 26, 2019
Operation
Air carrier
Aircraft
N506AS
Make and model
Boeing 737890
Aircraft serial
35690
Aircraft time
40,319 hours, 12,355 cycles
System (JASC)
7603 · Power Lever
Part
Unknown
Condition
Malfunctioned
Location
Throttle Sys
Stage of operation
CL
How discovered
O
Nature of condition
O
Precautionary procedure
O

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

DURING CLIMB FROM FL360 TO FL380 A THROTTLE SPLIT DEVELOPED UP TO APPROX ONE KNOB WIDTH WITH THE NR 2 THROTTLE HIGHER THAN NR 1. AT CLIMB POWER BOTH ENGINES WERE PRODUCING FULL THRUST AND EQUAL ON ALL PARAMETERS. EXCEPT FOR THROTTLE SPLIT. AT POWER REDUCTION BOTH THROTTLE LEVERS MOVED BACK TOGETHER HOWEVER THE THRUST ON THE NR 2 ENGINE REMAINED AT 100.5 WHILE NR 1 REDUCED TO ABOUT 90.0 WITHIN ABOUT 30 SEC BOTH ENGINES STABILIZED AT THE SAME CRUISE POWER WITH NO THROTTLE SPLIT. GROUNDED - YES. ACCOMPLISHED THRUST LEVER ANGLE RESOLVER ADJUSTMENT TEST. ALL TASK POSITIONS NORMAL SYSTEM THRUST LEVERS TEST NORMAL IAW AMM 76-11-05-820 AND FIM 76-05 TASK 801. PERFORMED AUTOTHROTTLE BITE PROCEDURE FIM 22-31 TASK 801 NO FAULTS RECORDED.