Which statement describes the primary purpose of shielding in avionics?

Which statement describes the primary purpose of shielding in avionics?

• A. To improve mechanical strength.
• B. To increase cable flexibility.
• C. To reduce radiated electromagnetic interference by containing electromagnetic fields.
• D. To change the electrical resistance of cables.

Answer: (C)

Shielding around avionics cables and equipment is meant to keep electromagnetic energy from escaping into or entering surrounding circuitry. A conductive or magnetic shield surrounds the conductors and, when tied to ground, provides a path for noise to be diverted away. This containment reduces radiated electromagnetic interference, which is crucial in aircraft where sensitive navigation, communication, and control systems can be affected by nearby electronic devices. Shielding doesn’t primarily change mechanical strength, cable flexibility, or the DC resistance of the conductors; those are separate cable characteristics.

Shielding around avionics cables and equipment is meant to keep electromagnetic energy from escaping into or entering surrounding circuitry. A conductive or magnetic shield surrounds the conductors and, when tied to ground, provides a path for noise to be diverted away. This containment reduces radiated electromagnetic interference, which is crucial in aircraft where sensitive navigation, communication, and control systems can be affected by nearby electronic devices. Shielding doesn’t primarily change mechanical strength, cable flexibility, or the DC resistance of the conductors; those are separate cable characteristics.