What types of boundary layers can be found on an aerofoil? - SPL

Question id 613 - Principles of Flight (Aeroplane) - SPL - Sailplane Pilot License

Laminar boundary layer along the complete upper surface with non-separated airflow

Turbulent layer at the leading wing areas, laminar boundary layer at the trailing areas

Turbulent boundary layer along the complete upper surface with separated airflow

Laminar layer at the leading wing areas, turbulent boundary layer at the trailing areas