Service difficulty report · Flap System · Boeing 737924ER

Difficulty date
June 28, 2021
Submitted
June 28, 2021
Operation
Air carrier
Aircraft
N68452
Make and model
Boeing 737924ER
Aircraft serial
40005
Aircraft time
29,128 hours, 10,426 cycles
Part
Flap System
Condition
Malfunctioned
Stage of operation
LD
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

TRAILING EDGE FLAPS ASYMMETRY. PREVIOUSLY REPORTED YESTERDAY THIS ITEM HAS BEEN LOCKED BY THE TOMC SR MANAGER DUE TO REPEAT T/E ASYMMETRY LOCKOUT FOR LANDING AND THE FLIGHT CREW DECLARING AN EMERGENCY. NEED POSITIVE FINDING/FIX. SKEW SENSOR #1 IS STILL SHOWING ERRONEOUS VALUES. WAS RECENTLY REPLACED, SO NEED TO TROUBLESHOOT WIRING. IF WIRING OK, CHECK INSTALLATION. UNLOCKED FOR UPDATE. PERFORMED BITE ON FSEU FOUND MSG 27-53250 FLAP 1 SKEW, DEFECTS NOTED, ALSO PERFORMED RESISTANCE CHECK FOR SKEW SENSORS *EMERGENCY DECLARED FOR LANDING* ACCOMPLISHED SENSOR NO.1 AND 8 WIRING INSULATION CHECK NO SYSTEM FUNCTIONAL TEST FOUND SKEW SENSOR 1 READING FLAPS UP ADD EMP:U352700 1 AND 8, FOUND WITHIN LIMITS, PERFORMED FLAP SKEW DETECTION 304.2 FLAP15,151 FLAP 40,236. SKEW SENSOR 8 FLAPS UP55.2 FLAPS15= FLAPS40=123, ALL RESULTS WITHIN LIMITS ACCORDING TABLE 502, WORK PERFORMED IAW AMM 27-59-00 NEED TO CONTINUE WITH STEP E5 OF FIM 27-59 TASK 801. ADD EMP:U352700 RELOCKED L/P UNLOCKED FOR UPDATE T/S PER FIM TASK 27-59 TASK 801. TE FLAP SUPPORT NO. 1 SKEW PROBLEM. PER STEP E5 CHECKED FLAP DRIVES NO 1&8 FOR A SKEW. NO SKEW FOUND, ALL MEASUREMENTS ARE WITHIN LIMITS. NEXT STEP PER 5C IS STEP G FAULT ISOLATION PROCEDURE - FLAP NOT SKEWED. LOCKED UNLOCKED FOR SIGN OFF REF LOG PAGE 6557648. COMPLETED STEG G AS PER FIM TASK 27-59 TASK 801. OPS CHECK GOOD. NO FURTHER DEFECTS NOTED. ADD EMP:U354048,U344428. AS PER LP 6557648 REMOVED AND REPLACED #2 SKEW SENSOR IAW AMM