Service difficulty report · Autothrottle Sys · Boeing 737890

Difficulty date
September 30, 2019
Submitted
October 2, 2019
Operation
Air carrier
Aircraft
N560AS
Make and model
Boeing 737890
Aircraft serial
35179
Aircraft time
50,057 hours, 14,978 cycles
Part
Autothrottle Sys
Condition
Malfunctioned
Stage of operation
NR
How discovered
9
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

AUTOTHROTTLE WILL ENGAGE, BUT DISENGAGES AFTER ABOUT 3 SECS, ANY MODE, EITHER AUTOPILOT ENGAGED OR NO A/P ENGAGED. GROUNDED - YES. REF B737-800 FIM 22-31 TASK 801 A/T BITE PROC., FOUND ASM-1 FAIL ON DISCREPANCY FLIGHT IN FAULT REVIEW. #1 THROTTLE WON'T MOVE DURING INTERACTIVE SERVOMOTOR TEST. RESET POWER TO SYST BY PULLING, THEN RESETTING A/T DC1 C/B. A/T OPS NRML PER FIM 22-31 TASK 801 - CURRENT STATUS & INTERACTIVE THROTTLE TESTS OPS NRML - NO FAULTS. BOTH THROTTLES MOVE TOGETHER AND SMOOTHLY.