Heading Indicator — CockpitConnect

Overview

The Heading Indicator (HI), also known as the directional gyro (DI), sits bottom-centre in the six-pack "T" arrangement. It shows aircraft heading on a rotating compass card against a fixed lubber line, with a heading bug used by the S-TEC autopilot's HDG mode.

Construction

Like the other six-pack instruments, this gauge is built as a self-contained module:

Bezel / Face Plate — 3D-printed bezel with a fixed lubber line marking
Dial / Needle — rotating compass card in place of a needle
Internal Mechanics — stepper motor driving the compass card; a second stepper (or a knob with encoder feedback) drives the heading bug for the autopilot
Back Housing — 3D-printed enclosure mounting to the MIP frame's instrument cutout
PCB & Controller — ESP32 driving the compass card and heading bug mechanisms
Lighting — backlighting for night/IFR panel illumination

X-Plane Integration

sim/cockpit2/gauges/indicators/heading_vacuum_deg_mag_pilot   compass card (vacuum gyro)

# Heading bug (flown by the S-TEC autopilot's HDG mode)
sim/cockpit2/autopilot/heading_dial_deg_mag_pilot
sim/autopilot/heading_up / heading_down / heading_sync        bug knob and its push

# Drift knob: realigns the card with the compass
sim/instruments/DG_sync_up / DG_sync_down

The steam Skyhawk's heading indicator is a vacuum gyro, so its card follows the vacuum dataref and drifts or fails with the vacuum system. In the Cessna 172 (six-pack) Blueprint the bug knob is an encoder on GPIO 25 and 26 with its push on 27, and the drift knob an encoder on GPIO 32 and 33. The card turns all the way round and needs a continuous-rotation gauge stepper, which CockpitConnect doesn't drive yet.

Status

Planning — design not yet started.