FAA Aviation Mechanic Airframe (AMA)Airframe Electrical and InstrumentsHard
A technician is installing new wiring for a dual-redundant flight control system with a primary and a backup electrical path. Whenever practical, the technician routes the wire bundles for the primary and backup systems through physically separate areas of the airframe rather than bundling them together. What is the primary reason for this separation?
- ATo minimize electromagnetic interference between AC and DC circuits
- BTo prevent a single fault, chafe point, or physical damage from affecting both systems simultaneously
- CTo simplify color-coding requirements for wire identification
- DTo reduce the overall length of wire required for the installation
Show answer & explanationAnswer & explanation
Correct answer: B. To prevent a single fault, chafe point, or physical damage from affecting both systems simultaneously
Physical separation of redundant wire bundles ensures that a single event such as chafing, fire, mechanical damage, or a short circuit cannot disable both the primary and backup systems at the same time, preserving system redundancy.
Why the other options are wrong
- A. While EMI is a wiring consideration, it is not the primary reason for redundant system separation.
- C. Color-coding is a labeling convenience, not the reason for physical routing separation.
- D. Wire length reduction is not the safety-driven reason for redundant bundle separation.
Redundant Wire Bundle Separation
A wiring installation practice of physically separating wire bundles for redundant systems so that a single localized fault cannot disable both systems.
- Protects against single-point failures like chafing, fire, or mechanical damage
- Applies to critical/redundant flight control and electrical systems
- Often required by design standards for essential and backup circuits
Memory trick: Never put both parachutes in the same bag — separate redundant bundles.