What should pilots rely on during critical flight phases if not all checklists are performed from memory?

During critical flight phases, pilots should rely on published checklist procedures. These checklists are designed to ensure that all necessary actions and considerations are systematically addressed, especially during high-stress or high-workload situations. Published checklists are grounded in safety protocols and operational standards, which have been developed through extensive research and practical application in aviation environments.

Using a published checklist helps minimize the risk of omitting crucial tasks or steps that could lead to safety hazards, particularly in critical phases such as takeoff, landing, or emergency situations. They provide a standardized approach to procedures that all pilots and crew members can follow, ensuring consistency in operations.

Other options, while related to a pilot's training and experience, do not provide the systematic, thorough approach that published checklists do. Expert knowledge and experience from previous flights may inform decision-making but can be subjective and may not cover all necessary items. Checklists from data cards can support a pilot's workload but are not as comprehensive and possibly not as rigorously vetted as official published procedures. Therefore, relying on published checklist procedures is the most reliable approach for ensuring safety and compliance with aviation protocols.