Whose responsibility is it that the aircraft is free of Ice, Snow and Frost accumulation prior to take off?

The Pilot-in-Command (PIC) is ultimately responsible for ensuring that the aircraft is free of ice, snow, and frost accumulation prior to takeoff. According to aviation regulations and practices, the PIC must verify that the aircraft is airworthy and capable of safe operation, which includes performing checks on critical surfaces to prevent ice accumulation. Ice, snow, or frost can significantly affect the aerodynamics of the aircraft, leading to compromised flight performance, including increased stall speeds and reduced control effectiveness during critical phases of flight.

While ground handlers and maintenance personnel play important roles in aiding the de-icing process and preparing the aircraft, it is the PIC who must make the final assessment and decision regarding the aircraft's readiness for takeoff. This responsibility is in line with the principles of crew resource management, where the PIC utilizes available resources and personnel to ensure safety and compliance with regulations.