FAA Aircraft Dispatcher (ADX)Regulations (Part 121)Hard
A dispatcher is selecting an alternate airport for a Part 121 flight and the only instrument approach available at that airport is a nonprecision approach. With no other alternate minimums published, what ceiling and visibility must forecast weather meet at ETA for that airport to be listed as the alternate under 14 CFR 121.625?
- A800-foot ceiling and 2 statute miles visibility
- B1,000-foot ceiling and 3 statute miles visibility
- C1,500-foot ceiling and 3 statute miles visibility
- D600-foot ceiling and 2 statute miles visibility
Show answer & explanationAnswer & explanation
Correct answer: A. 800-foot ceiling and 2 statute miles visibility
Under 14 CFR 121.625 and the associated standard alternate minimums, an airport served only by a nonprecision approach requires forecast weather of at least an 800-foot ceiling and 2 statute miles visibility to be used as an alternate, absent other published alternate minimums. Airports with a precision approach use the lower 600-foot/2-mile standard.
Why the other options are wrong
- B. 1,000-3 is not a standard alternate minimum figure used here.
- C. 1,500-3 is excessively conservative and not the standard figure.
- D. 600-2 is the standard minimum for airports with a precision approach, not nonprecision.
Standard Alternate Minimums (121.625)
Default weather minimums used to qualify an airport as an alternate when no other alternate minimums are published, based on approach type available.
- Precision approach available: 600-foot ceiling, 2 SM visibility
- Nonprecision approach only: 800-foot ceiling, 2 SM visibility
- No instrument approach: must allow descent, approach, and landing under VFR
Memory trick: 'Six hundred, Eight hundred' — precision beats nonprecision by 200 feet