Which statement best describes a navigation-systems requirement for extended over-water operations?

• A. A single long-range navigation system is never allowed.
• B. At least two independent navigation systems are required.
• C. A single long-range navigation system may be authorized in certain geographic areas.
• D. RNAV is required in all extended over-water operations.

Answer: (C)

Extended over-water operations focus on maintaining reliable navigation over long distances where failures could have serious consequences. The usual safety mindset is to have two independent long-range navigation systems so a single failure doesn’t leave you without accurate position. Yet the regulations also recognize that in certain geographic areas with proven navigation coverage and established procedures, a single long-range navigation system may be authorized if the operator’s Ops Specifications allow it and appropriate safeguards are in place. That’s why this option is the best: it captures the reality that a single long-range navigation system can be permitted in specific regions, rather than being universally required.

The other statements are too absolute. A single long-range navigation system is not categorically prohibited in all ETOW operations, since there are areas where a single system is authorized. Requiring two independent navigation systems in all ETOW operations ignores the area-based allowances. And requiring RNAV in all extended over-water operations goes beyond what the cited rule mandates, since RNAV isn’t universally required for every ETOW flight.