The flight testing of communications systems is avionics flight testing in its most basic form, but it does illustrate many of the common factors seen in the more complex systems. The testing of communication systems occurs more often than one would expect. Radios are often upgraded, which requires a flight test program, but these upgrades may be many years apart. What occurs on a more frequent basis is the relocation of antennas or the installation of stores or other obstructions that may affect communications. Some flight testing may be required to ensure that no degradation of communications due to these modifications has occurred. Radios, because they transmit as well as receive radio frequency (RF) energy, are also key players in electromagnetic interference/electromagnetic compatibility (EMI/EMC) testing. This testing is addressed later in this chapter.

Chapter Contents:

• 4.0 Overview
• 4.1 Communications Basics
• 4.2 Aircraft Communications Equipment
• 4.3 Test Requirements
• 4.4 The Three Steps in Avionics Testing
• 4.5 Communications Test Plan Matrix
• 4.6 Executing the Matrix
• 4.7 Other Considerations in Communications Tests
• 4.8 Effects of Stores, Landing Gear, and Flaps
• 4.9 Effects of Weather
• 4.10 Logistics
• 4.11 Boredom
• 4.12 Speech Intelligibility
• 4.13 Electromagnetic Interference/Electromagnetic Compatibility
• 4.14 EMI/EMC Testing
• 4.15 EMI/EMC Test Issues
• 4.16 EMI/EMC Elimination
• 4.17 Selected Questions for Chapter 4

Inspec keywords: aerospace testing; avionics; aircraft communication; radiofrequency interference; air safety; electromagnetic compatibility

Other keywords: flight test program; electromagnetic interference testing; radio frequency energy; electromagnetic compatibility testing; communications flight test; avionics flight testing; communication degradation

Subjects: Aerospace testing and simulation; Aircraft electronics; Mobile radio systems; Electromagnetic compatibility and interference