ATA 27

Flap Limit Switches
With the issuance of Service Bulletin 1124-27-153, Mandatory Replacement of the Inboard Flap Actuators, it is an excellent time to inspect the position switches on the actuators. The left actuator has six and the right has two. Pay particular attention to the rollers; check them for flat spots and ease of turning. A drop of LPS 1 on each one will help prevent further problems. Make sure the arms are true and not bent; if they are bent, now is a great time to replace them. Wringing out the switches can also be done at this time. Make sure the 0°, 40°, and 42° switches are good; if high resistance is noted, replace the switch. If you find multiple problems, you would be money and time ahead to replace the entire switch rack.