What must be included in pre-flight planning according to air law?

Pre-flight planning is a critical component of flight operations governed by air law. It ensures that all necessary precautions and assessments are made to facilitate a safe and successful flight. The correct choice emphasizes key elements involved in this process, which are weather assessments, route planning, and compliance with regulations.

Weather assessments are crucial because they allow pilots to understand atmospheric conditions that could impact the safety and performance of the flight. For instance, knowledge of wind patterns, visibility, and potential for turbulence is vital for determining the safest routes and altitudes to fly.

Route planning is another essential factor. It involves creating an efficient flight path that considers air traffic control regulations, navigational aids, and available airspace. This process not only optimizes fuel consumption and travel time but also ensures adherence to safe flying practices.

Compliance with regulations is indispensable in air law. Pilots must ensure that they are following all applicable laws and guidelines, including those set by aviation authorities. This compliance relates to licensing, operational limits, and any airspace restrictions.

While the other choices also relate to aspects of flight preparation, they do not encompass the broader and necessary elements of safety and regulatory adherence required in pre-flight planning as comprehensively as the correct choice does.