AF 4500s TT VSVG heading bug control

[Rob Hickman]

SHould the heading bug (and alt bug) on the 4500s control roll and pitch of the Tru Track VSVG? What is the function of the autopilot source switch?

I have completed the troubleshooting procedure for the autopilot per the manual but it assumes an AF Pilot. I have no AP roll control with the heading bug. The autopilot source switch is set to output from the Arinc box.

Thanks,
Chris Stone

1. Make sure the A/P is in GPSS mode

2. Make sure the AP/FD LAT source is set for Heading

3. If it still does not work double check the ARINC Autopilot wiring to the AF-ARINC module.

This is almost always caused by bad wiring between the AF-ARINC module and AP.