What specific training is unnecessary for an SIC with a check airman?

The correct answer highlights that the Second-in-Command (SIC) under the supervision of a check airman does not need to complete a proficiency check. This is because the check airman already oversees the SIC's performance, assessing their capabilities during actual flights or simulator training. Proficiency checks are typically required for pilots who are not under the direct supervision of a check airman or who are seeking to validate their qualifications independently.

In this case, since the SIC is working alongside a check airman, they are not required to undergo an additional proficiency check that would typically be mandated for an independent pilot. This arrangement ensures that the SIC can operate while still maintaining safety and compliance regulations under the check airman’s oversight, allowing for practical assessment of their competencies in real-time scenarios.

The other options imply certain levels of independence or oversight that are not applicable when a check airman is involved. While the SIC does have some operational autonomy, the necessary training and oversight provided by the check airman negate the need for a redundancy like a separate proficiency check.