Final answer:
In order for a turbo-jet or turbofan aircraft to legally take-off, it must have a minimum control speed (Vmc) certification.
Step-by-step explanation:
In order for a turbo-jet aircraft or turbofan aircraft with a MCTOW of 12,566 pounds or more to legally take-off under Part VII operations, it must have a minimum control speed (Vmc) certification.
Minimum control speed (Vmc) is the minimum speed at which the aircraft is still controllable in the event of an engine failure. It represents the slowest speed at which the pilot can maintain control of the aircraft with a failed engine.
The Vmc certification ensures that the aircraft is capable of maintaining control during critical flight phases, such as take-off, at the specified weight limit.