What was found
FLIGHT 7557 IAD-SCE, PILOT REPORTED, DURING THE CLIMBOUT UNABLE TO TRIM AIRCRAFT WITH EITHER LEFT OR RIGHT YOKE PITCH TRIM SWITCHES. STANDBY TRIM FUNCTIONED NORMALLY. AIRCRAFT RETURNED SAFELY TO IAD.
As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
FLIGHT 7557 IAD-SCE, PILOT REPORTED, DURING THE CLIMBOUT UNABLE TO TRIM AIRCRAFT WITH EITHER LEFT OR RIGHT YOKE PITCH TRIM SWITCHES. STANDBY TRIM FUNCTIONED NORMALLY. AIRCRAFT RETURNED SAFELY TO IAD.