What limitation applies to pilots regarding aircraft with a gross weight over 12,500 pounds?

Holding a type rating is essential for pilots operating aircraft with a gross weight over 12,500 pounds because these aircraft can have complex systems and performance characteristics that differ significantly from smaller aircraft. A type rating ensures that the pilot has undergone specific training and has demonstrated proficiency in the operation of that particular aircraft model. This requirement reflects the FAA's focus on safety by ensuring that pilots are adequately trained and assessed for each specific model they fly, especially given the complexities and responsibilities associated with larger aircraft.

This limitation is crucial because it verifies that the pilot is familiar with the aircraft's systems, performance criteria, and handling characteristics, which can be significantly different from flying smaller aircraft. Thus, without the appropriate type rating, a pilot is not permitted to operate these larger aircraft, aligning with regulatory standards to maintain operational safety and proficiency.