SDR 20000607SH017

Service difficulty report · Spring · Boeing 737*

Difficulty date: April 24, 2000
Submitted: June 7, 2000
Operation: Air carrier
Make and model: Boeing 737*
System (JASC): 2740 · Stabilizer Control System
Part: Spring
Part number: 69778551
Condition: Broken
Location: Horizontal Stab
Part time: 18,969 hours
Component: Horiz Stab Trim · Boeing
Component part number: 654997025
Stage of operation: IN
How discovered: V
Nature of condition: O
Precautionary procedure: K

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

What was found

SPRINGS, PN 69-77855-1, ARE BROKEN IN THE AUXILIARY BRAKE SYSTEM CAUSING THE UNIT TO BIND AND JAM. IMPROPER HEAT-TREATING, AUSTENITE, FATIGUE AND INCREASED SPRING COIL STRESSES. SUBMITTER STATED SPRINGS, PN 69-77855-1, ARE TO BE REPLACED WITH PN 69-77855-2 SPRINGS ON ACTUATOR ASSEMBLIES MANUFACTURED PRIOR TO S/N KE01730 PER BOEING SL 737-SL-27-090-B. (X)