Which of the following is true about an ETOPS Group 1 Significant System?

• A. Has fail-safe characteristics directly linked to the degree of redundancy provided by the number of engines on the airplane
• B. Is a decorative system
• C. Is only on single-engine airplanes
• D. Is a system not used during ETOPS

Answer: (A)

ETOPS Group 1 Significant Systems are designed with reliability that matches the airplane’s engine redundancy. The system must be fail-safe or able to continue functioning safely even if an engine fails, and the level of redundancy provided by the number of engines dictates how that fail-safe behavior is implemented. That’s why this statement is correct: the system’s safety features are directly linked to how many engines the aircraft has. This isn’t a decorative system, it isn’t limited to single-engine airplanes, and these systems are indeed used during ETOPS to support continued safe operation with engine-out scenarios.