When should you consider an alternate airport with a non-GPS approach?

The correct choice is based on the consideration of the 1-2-3 rule, which is a guideline to determine whether an alternate airport is needed when planning an IFR flight. Specifically, this rule states that you should have an alternate airport if your destination airport's weather is forecasted to be below 2,000 feet ceiling or less than 3 statute miles visibility at the time of arrival. The alternative airport must have a compatible approach available.

Using the 1-2-3 rule helps ensure that pilots maintain safety by accounting for potential weather changes and the ability to reach an alternate destination safely should the need arise. This is particularly important when operating in environments where access to precision approaches, such as GPS, may not be available.

Other choices provide different considerations related to alternate airport planning but do not align as directly with the specific requirements outlined by the 1-2-3 rule. For instance, the capacity of the aircraft to operate VFR, the presence of GPS-capable aircraft, or flying internationally are relevant factors but do not specifically dictate the necessity for an alternate airport in the same manner as the 1-2-3 rule does.