Dependent Position Determining

The dependent position determining systems provide information to determine position and is mainly dependent on ground installations or orbital satellites. It includes the following:

Mode S Transponder

The mode S transponder provides coded responses to Air Traffic Control (ATC) ground radars and Traffic Collision Avoidance System (TCAS) interrogations. It receives Traffic Information System (TIS) transmissions and forwards them to the indicating/recording systems for processing and display. It also provides Automatic Dependent Surveillance-Broadcast (ADS-B) for improved situational awareness and safety of flight.

The transponder receives interrogations from Air Traffic Control (ATC) and the Traffic Collision Avoidance System (TCAS). It receives Traffic Information Service (TIS) to provide traffic advisory information. The Automatic Dependent Surveillance-Broadcast (ADS-B) sends position, velocity, and heading data to other aircraft and ground stations. The central display system, through the general computers system, are used to control the transponder and display TIS advisories. The transponder includes the mode S transponder (GTX) and the transponder antenna.

Mode S transponder (GTX)

The mode S transponder (GTX) receives interrogations from ATC ground radar, TCAS, and TIS transmissions at the frequency of 1030 MHz. It processes the signals, replies coded responses for modes A, C, and S at the frequency of 1090 MHz, and sends TIS advisory information to the integrated avionics unit (GIA). The mode S transponder (GTX) is mounted in a dedicated mounting rack to facilitate replacement of the Line Replaceable Unit (LRU). It is located on the avionics shelf in the aft center fuselage.

Transponder antenna

The transponder antenna is used by the mode S transponder (GTX) to receive and transmit radio signals. It is a blade antenna that is located on the right side of the belly, aft of the landing gear.

Mode S Transponder - Operation

The mode S transponder (GTX) is energized with 28 VDC from the MAIN bus and can be isolated with the XPDR circuit breaker.

The mode S transponder (GTX) transmits and receives radio signals through its BOTTOM ANTENNA connection to and from the transponder antenna.

The mode S transponder (GTX) receives commands, encoded altitude data, and mode A codes from the integrated avionics unit (GIA) through a bidirectional RS-232 data bus. The data bus is also used to send status and TIS data to the integrated avionics unit (GIA).

NAV/VOR/GS

The NAV/VOR/GS receives and processes transmissions from VHF Omnidirectional Range (VOR), Localizer, and Glide Slope (GS) signals from ground based stations to provide navigation data. The receivers are combined with the general computers. The central display system lets the operator control the NAV/VOR/GS and see the navigation data. The audio integrating system processes and distributes the audio from the NAV/VOR/GS receiver. The NAV/VOR/GS consists of the NAV/VOR/GS diplexer and the NAV/VOR/GS antenna.

The NAV/VOR/GS consists of two receivers that are integral with the integrated avionics unit (GIA).

The NAV/VOR/GS receives VOR/Localizer signals in the frequency range of 108.00 to 117.95 MHz in 50 kHz increments. It receives the GS signals in the frequency range 328.6 to 335.4 Mhz as paired with the frequency tuned on the VOR/Localizer receiver.

The Primary Flight Display (PFD) and the Multi-Function Display (MFD) have functions to set the VOR/Localizer frequency, control the squelch and volume of the receiver audio, and to display navigation data.

The audio panel (GMA) processes and distributes the audio from the NAV/VOR/GS.

NAV/VOR/GS diplexer

The NAV/VOR/GS diplexer allows operation of the VOR/Localizer and the GS from a single VOR/GS antenna. It is located on the avionics shelf in the aft center fuselage.

NAV/VOR/GS antenna

The NAV/VOR/GS antenna is a V shaped dipole with fixed elements and an integral ferrite balun. It covers the frequency ranges 108-118 MHz (VOR/Localizer) and 329-335 MHz (GS). It is located at the top of the vertical stabilizer.

NAV/VOR/GS - Operation

The NAV/VOR/GS antenna receives the VOR/Localizer, and GS signals.

The NAV/VOR/GS diplexer directs the VOR/Localizer signals to the NAV ANTENNA input of the integrated avionics unit (GIA). It directs the GS signal to the GS ANTENNA input of the integrated avionics unit (GIA).

The integrated avionics unit (GIA) processes the VOR/Localizer, and GS signals. The navigation data is sent to the PFD and the MFD for display.

The audio signal of the NAV receiver is supplied from the VOR/LOC 500Ω AUDIO OUT HI connection of the integrated avionics unit (GIA) to the NAV AUDIO IN HI connection of the audio panel (GMA). The audio signal return is from the NAV AUDIO LO to VOR/LOC 500Ω AUDIO OUT LO connections.

The PFD and the MFD send control messages to the integrated avionics unit (GIA) for the NAV/VOR/GS.

Global Positioning System (GPS)

The GPS receives and processes signals from navigation satellites to provide navigation data.

The Global Positioning System (GPS) is part of the Garmin G1000H NXi integrated avionics system (IAS). It receives and processes signals from navigation satellites to provide navigation data information to the pilot.

The GPS receives and processes satellite signals. It can use 12 GPS satellites and one Wide Area Augmentation System (WAAS) satellite simultaneously. It can also use additional Satellite-Based Augmentation System (SBAS) such as European Geostationary Navigation Overlay Service (EGNOS) and Multi-functional Satellite Augmentation System (MSAS). The receiver for GPS signals and their processing are integral with the general computers. The GPS navigation information is shown on the central display systems.

Global Positioning System (GPS) - Operation

The satellite GPS signals are received by the COM/GPS antenna.

The satellite GPS signals are directed to the GPS ANTENNA connector of the integrated avionics unit (GIA) for processing.

The integrated avionics unit (GIA) provides the GPS navigation data to the central display systems. The navigation data is normally shown on the Multi-Function Display (MFD).

The integrated avionics unit (GIA) also provides the GPS navigation data to the Air Data\Attitude and Heading Reference System (ADAHRS) (3421CM1) as a reference signal.