What is the minimum visibility value that is not authorized for use?

What is the minimum visibility value that is not authorized for use?

• A. 1/2 statute mile
• B. 1 statute mile
• C. 3/4 statute mile
• D. 2 statute miles

Answer: (A)

Visibility minima for instrument operations come from an official list of authorized values. Not every fraction is permitted as a minimum, only the values published by the regulatory authority. Among the options, 1/2 statute mile isn’t on that official list, so it can’t be used as a published minimum. The other values shown (1 mile, 3/4 mile, 2 miles) are standard minima that can be used depending on the procedure and operator’s published limits. So the smallest value that isn’t authorized is 1/2 statute mile.

Visibility minima for instrument operations come from an official list of authorized values. Not every fraction is permitted as a minimum, only the values published by the regulatory authority. Among the options, 1/2 statute mile isn’t on that official list, so it can’t be used as a published minimum. The other values shown (1 mile, 3/4 mile, 2 miles) are standard minima that can be used depending on the procedure and operator’s published limits. So the smallest value that isn’t authorized is 1/2 statute mile.