Duncan Aviation Avionics Techs have seen failures on the Rockwell Collins Annunciator Panel in the APS 65 Flight Control System (AP65). This unit is a part of the autopilot system that also includes, among other things, an autopilot computer (APC-65), controllers, mode selectors, input sensors and servos.
The annunciator panels are in the flight control in the cockpit. They keep the pilot continuously informed about the mode status of the autopilot and Flight Director. If these annunciators fail, pilots may receive false or inaccurate information / readings during flight.
To be seen, annunciators are lit from behind by several small lamps. For example, the annunciator bar in the autopilot controller (APP-65) has approximately 12 individual lamps. The annunciator connected with the Flight Director (FCP-65 / 65A) has a few more. There may also be a remote annunciator panel (MAP-65) with a similar number of lights.
The most common failure of an annunciator panel is a burned out lamp. The panels need to be sent to an authorized repair center every time a lamp is burned out.
Rockwell Collins has issued a Service Bulletin that replaces all the lamps in each unit. These lamps are an alternate part number that is supposed to be more reliable with a longer life.
Each unit has its own SB. To get the correct SB for your unit, contact any one of the avionics instruments tech reps at Duncan Aviation.
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