In Alternate Derived Minimums, how much is added for 2 NAVAIDs?

In Alternate Derived Minimums, how much is added for 2 NAVAIDs?

• A. 200 feet and 1/2 mile
• B. 400 feet and 1 mile
• C. 100 feet and 1/4 mile
• D. 50 feet and 1/8 mile

Answer: (A)

When planning an alternate, the extra margins added to the approach minimums depend on how many NAVAIDs back up the final approach. If the alternate minimums are derived from an approach that uses two NAVAIDs, you add 200 feet to the minimums and 1/2 mile to the visibility. The idea is that the redundancy of two nav aids reduces the risk of mis-navigation, so a smaller cushion is needed compared with using only one NAVAID. If only one NAVAID supported the approach, the padding would be larger (400 feet and 1 mile). The other numbers shown reflect those single-NAVAID or other scenarios, not the two-NAVAID case.

When planning an alternate, the extra margins added to the approach minimums depend on how many NAVAIDs back up the final approach. If the alternate minimums are derived from an approach that uses two NAVAIDs, you add 200 feet to the minimums and 1/2 mile to the visibility. The idea is that the redundancy of two nav aids reduces the risk of mis-navigation, so a smaller cushion is needed compared with using only one NAVAID. If only one NAVAID supported the approach, the padding would be larger (400 feet and 1 mile). The other numbers shown reflect those single-NAVAID or other scenarios, not the two-NAVAID case.