Type Rating Knowledge — Cessna 172S NAV III
Avionics — G1000 and the GFC 700 AFCS
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Two identical screens doing two different jobs
The G1000 puts two IDENTICAL display units on the panel. The one in front of the pilot is configured as the PFD; the one to the right is configured as the MFD. Identical is the important word — they are the same part number doing different jobs because of how they are configured, not because one is a flight instrument and the other is a map. The PFD carries roll and pitch, heading and course, altitude, airspeed and vertical speed, and it also controls and displays every communication and navigation frequency and the aeroplane’s warning and status annunciations. The MFD carries a large scalable moving map with traffic, lightning and weather overlaid on it, and it is the principal display for all engine, fuel and electrical parameters.
- AHRS (GRS) — Attitude and heading reference system in the tailcone — attitude and flight characteristics.
- MAGNETOMETER — In the left wing panel; interfaces with the AHRS to provide heading.
- ADC (GDC) — Air data computer behind the panel, forward of the MFD, with the OAT probe wired to it.
- ENGINE MON (GEA) — Engine monitor receiving every engine and airframe sensor — CHT, EGT, RPM, fuel flow and the fuel gauging system — and transmitting to the engine display computers.
- XPDR (GTX) — Mode S transponder in the tailcone avionics racks, providing Mode A, C and S. It is controlled from the PFD, not from a box of its own.
- XM DATALINK (GDL) — GDL-69A XM weather and radio data link in the tailcone, on the high-speed bus to the MFD. A subscription is required for it to be used.
- GIA 1 — Integrated avionics unit 1, in a tailcone rack. Communications hub linking the peripherals to the displays, and it CONTAINS a GPS receiver, a VHF nav receiver, a VHF comm transceiver and the main system microprocessors.
- GIA 2 — Integrated avionics unit 2, identical to GIA 1. The FIRST unit to acquire a GPS 3-D navigation signal is the active GPS source — not a fixed priority.
- PFD (GDU) — Display unit in front of the pilot, configured as the primary flight display. It also controls and displays all comm and nav frequencies and the airplane system annunciations.
- AUDIO PANEL (GMA) — Between the two displays. It integrates the comm and nav digital audio, the intercom and the marker beacon — and it is the unit that controls REVERSIONARY mode for both displays.
- MFD (GDU) — Identical display unit to the right, configured as the multi-function display: scalable moving map, traffic, lightning and weather overlays, and the principal display for engine, fuel and electrical parameters.
- COM 1 — VHF communication transceiver inside GIA 1.
- NAV 1 — VHF navigation receiver inside GIA 1, fed by a blade antenna on the vertical stabilizer.
- GPS 1 — GPS receiver inside GIA 1, fed by the COM 1/GPS 1 dual-mode antenna on the right of the cabin roof.
- COM 2 — VHF communication transceiver inside GIA 2.
- NAV 2 — VHF navigation receiver inside GIA 2, fed by the blade antenna on the other side of the fin.
- GPS 2 — GPS receiver inside GIA 2, fed by the COM 2/GPS 2 dual-mode antenna on the left of the cabin roof.