Why We Still Reference Older FAA Weather Publications

In some of our courses, you may notice references to older FAA publications such as Aviation Weather AC 00-6A (1975). While these documents have been officially cancelled and replaced by the Aviation Weather Handbook, they remain important for both training and exam preparation, and in some cases the content is only available in the legacy publications.

Why this matters:

Cancellation doesn’t mean inaccuracy. The FAA cancelled these publications to combine them into a single handbook, not because the information was wrong. The science, theory, and explanations remain valid today. What has evolved over time are the weather services, and where appropriate we provide the updated reference for current weather services.

Knowledge test questions still rely on older material. The FAA’s exam banks often lag behind current publications. In some cases, test questions can only be answered with information found in AC 00-6A, because that material is not included in the newer handbook. For example, only AC 00-6A defines the terms terms frontogenesis and frontolysis.

Older sources provide better detail. Some topics—such as air stability, fog formation, and wind shear—are explained more thoroughly in the legacy circulars. Using them helps you build a stronger foundation and ensures you don’t miss critical details.

For example, AC 00-6A explains air stability, front formation, and wind shear far more thoroughly than AC 00-6B or the Aviation Weather Handbook. Continuing to reference these legacy publications preserves access to essential knowledge that newer handbooks have reduced or excluded.

Our approach:

• We are gradually updating references to the Aviation Weather Handbook wherever the material matches.
• When the newer handbook does not cover information needed for the exam, we continue to cite the older publications so you know exactly where the testable knowledge comes from.
• This method balances accuracy, exam readiness, and efficient use of resources, while keeping our courses aligned with FAA standards.

Feedback:

Every course includes a “Suggest a Correction” button on questions and lessons. If you find a reference that looks outdated or incorrect, let us know. If the citation can be updated to a current source, we will make that change.