Communications and Navigation Systems

Course Description

AMT1241C — Communications and Navigation Systems is a college-credit, integrated lecture-and-laboratory course in Florida's Avionics and Aviation Maintenance Management college-credit programs. The course covers aircraft communications and navigation avionics: VHF/UHF/HF voice and data communications; very high frequency omnidirectional range (VOR); instrument landing systems (ILS); distance measuring equipment (DME); automatic direction finder (ADF); GPS and satellite-based augmentation systems (SBAS, including WAAS); area navigation (RNAV) and required navigation performance (RNP); and current-generation systems including Automatic Dependent Surveillance-Broadcast (ADS-B) Out and In.

This course is offered at Broward College, Eastern Florida State College, Polk State College, and other institutions with college-credit avionics programs. Successful completion supports preparation for the FCC General Radiotelephone Operator License (GROL) and continuing avionics-track coursework.

Learning Outcomes

Required Outcomes

Upon successful completion of AMT1241C, students will be able to:

• Explain the principles of radio-wave propagation: groundwave, skywave, line-of-sight; frequency-band characteristics; antenna theory introduction.
• Describe the operation and maintenance of aircraft VHF communications: 118.000–136.975 MHz aviation band; 25 kHz and 8.33 kHz channel spacing; squelch operation; antenna types and inspection.
• Describe the operation and maintenance of HF communications for long-range/oceanic operations.
• Describe the operation and maintenance of aircraft transponders: Mode A (identification), Mode C (altitude reporting), Mode S (selective addressing), and ADS-B Out (Automatic Dependent Surveillance-Broadcast).
• Describe the operation, calibration, and maintenance of VOR (VHF Omnidirectional Range) systems: 108–118 MHz band; conventional VOR vs. Doppler VOR; VOR reception and indication; VOT (VOR test signal) verification.
• Describe the operation and maintenance of Instrument Landing Systems (ILS): localizer, glideslope, marker beacons; CAT I, CAT II, CAT III approaches; ILS maintenance per AC 90-100.
• Describe the operation and maintenance of DME (Distance Measuring Equipment) and ADF (Automatic Direction Finder).
• Describe the operation and maintenance of GPS and satellite-based augmentation: GPS L1/L2 frequencies; WAAS (Wide Area Augmentation System); LPV approaches; FAA TSO-C145/C146 GPS receivers.
• Describe the operation of Area Navigation (RNAV) and Required Navigation Performance (RNP) systems including FMS (Flight Management System) integration.
• Describe the operation and FAA-mandated installation of ADS-B Out per 14 CFR 91.225 and 91.227 (FAA mandate effective 1 January 2020 for most controlled airspace).
• Use standard avionics test equipment: communications service monitor (e.g., IFR/Aeroflex 1500/2975, Viavi 8800), VOR/ILS test set, transponder/DME test set, GPS test set; aviation-specific signal generators.
• Read and interpret avionics installation drawings per FAA AC 43.13-1B Chapter 11 and SAE/RTCA installation standards.
• Document avionics maintenance and modification per 14 CFR 43, including FAA Form 337 (Major Repair and Alteration) for major avionics modifications.

Optional Outcomes

• Describe operation of SATCOM (Satellite Communications) systems for long-range aircraft.
• Describe operation of Mode S Enhanced Surveillance and ADS-B In applications (TIS-B, FIS-B).
• Apply introductory data-link communications: ACARS, CPDLC, FANS-1/A.

Major Topics

Required Topics

• Radio Theory and Antenna Fundamentals: Electromagnetic spectrum; radio-wave propagation modes; antenna types used in aviation (whip, blade, monopole, slot, dipole); antenna inspection and impedance considerations.
• VHF Communications: 118.000–136.975 MHz aviation band; AM modulation; 25 kHz and 8.33 kHz channel spacing; squelch; ICAO operational requirements.
• HF Communications: 2–30 MHz aviation HF band; SSB modulation; oceanic/remote-area applications; HF system maintenance.
• Transponders and Surveillance: Mode A/C/S transponders; ADS-B Out per 14 CFR 91.225/.227; 1090ES vs. UAT (978 MHz UAT in U.S.); transponder testing per 14 CFR 91.413 (24-month interval).
• VOR Navigation: 108–118 MHz; conventional and Doppler VOR; VOT signal; VOR receiver testing per 14 CFR 91.171 (30-day operational check or VOT verification).
• Instrument Landing Systems: Localizer (108.10–111.95 MHz); glideslope (329.15–335.0 MHz); marker beacons (75 MHz); CAT I, CAT II, CAT III approaches; ILS critical areas; ILS maintenance.
• DME and ADF: DME interrogator/transponder operation; 962–1213 MHz DME band; ADF operation in 190–1750 kHz LF/MF band.
• GPS and SBAS: GPS L1/L2 signals; WAAS (Wide Area Augmentation System); LPV approaches enabled by WAAS; TSO-C145/C146 receiver authorizations; RAIM (Receiver Autonomous Integrity Monitoring).
• Area Navigation: RNAV vs. RNP; FMS integration; database loading and currency; SID/STAR procedures.
• ADS-B: 14 CFR 91.225 (Out airspace), 91.227 (Out equipment); 1090ES and UAT data formats; performance testing; installation per FAA AC 20-165B.
• Avionics Test Equipment: Communications service monitor; VOR/ILS test set; transponder/Mode-S test set; DME test set; GPS test set; signal generators.
• Avionics Installation Standards: AC 43.13-1B Chapter 11; AC 43.13-2B Chapter 2; SAE/RTCA installation standards (DO-160, DO-178, DO-254 for software/hardware); EMI/EMC considerations.
• Documentation: 14 CFR Parts 43.9 and 43.11 record entries; FAA Form 337 for major repairs and alterations; weight-and-balance updates after avionics changes; equipment list updates.

Resources & Tools

• Thomas K. Eismin Aircraft Electronics (McGraw-Hill); Mike Tooley Aircraft Communications and Navigation Systems (Routledge)
• FAA AC 43.13-1B Chapter 11; AC 20-165B (ADS-B); AC 90-100 (RNAV); AC 90-105 (RNP)
• 14 CFR 91.171, 91.225, 91.227, 91.411, 91.413; 14 CFR Part 43
• RTCA standards (DO-160G, DO-178C, DO-254, DO-260B, DO-282B)
• Avionics service monitors and test sets; aircraft training installations
• FCC GROL study materials

Career Pathways

AMT1241C directly supports avionics-specific career paths in Florida's substantial aviation electronics market:

• Avionics Technician at FAA Part 145 repair stations; major Florida avionics repair stations include Bose Aviation (Daytona Beach area), Duncan Aviation (Battle Creek with Florida operations), and numerous independent shops.
• Avionics Installation Technician performing ADS-B retrofits, GPS upgrades, autopilot installations, and other aircraft electronics modifications.
• Avionics Bench Technician performing component-level repair on radios, navigation systems, and instruments.
• Field Service Representative for major avionics manufacturers (Garmin, Honeywell, L3Harris Collins Aerospace, Universal Avionics, Genesys Aerosystems) supporting Florida customers.
• Airline Avionics Technician at Florida airline maintenance bases supporting fleet avionics maintenance.

Special Information

FCC General Radiotelephone Operator License (GROL)

The FCC GROL is required for any avionics technician who performs internal adjustments to aircraft radios that transmit. The GROL exam (Elements 1 and 3) covers radio law and operation, broadcast technology, and electronics fundamentals. AMT1241C content directly supports preparation for the Element 3 exam; many institutions offer FCC examination as part of the avionics program.

FAA Aircraft Electronic Technician Recognition

The National Center for Aerospace and Transportation Technologies (NCATT) Aircraft Electronics Technician (AET) certification is widely recognized by Florida avionics employers and supports career advancement.

Course Format

Typically 3 credits, 60 contact hours integrated lecture and laboratory.

Articulation

AMT1241C typically articulates toward the A.S. in Avionics or A.S. in Aviation Maintenance Management at Florida College System institutions, and may transfer to upper-division programs at Embry-Riddle Aeronautical University.