When an alternate airport outside the United States has not prescribed takeoff minimums, what are the minimum weather conditions for takeoff?

In situations where an alternate airport outside the United States has not established specific takeoff minimums, the minimum weather conditions for takeoff are outlined by general guidelines for international operations. The correct choice of 900 feet of ceiling and 1.5 miles of visibility corresponds to the typical criteria used between various international aviation authorities. These parameters ensure a reasonable margin of safety for pilots departing an airport, particularly in unfamiliar areas where weather conditions may influence safety.

This minimum allows for enough altitude and visibility to navigate the departure safely, avoiding obstacles and ensuring an ability to follow air traffic control instructions. The choice represents a compromise between safety and operational feasibility, providing a baseline for pilots operating at less frequently trafficked airports, often characteristic of international destinations.

In the context of the other options, they may offer higher requirements, which are not necessary for conditions where specific minimums are not prescribed, leading to potential operational delays or restrictions.