Who maintains separation for IFR aircraft from other aircraft, terrain, and ground objects?

In the context of IFR (Instrument Flight Rules) operations, Air Traffic Control (ATC) is responsible for maintaining separation between IFR aircraft and other aircraft, terrain, and ground objects. This is a critical function, as it helps ensure the safe and orderly flow of air traffic, particularly in congested airspace and during adverse weather conditions.

When an aircraft is operating under IFR, it is operating in controlled airspace, where ATC provides instructions and clearances that include altitude assignments, routing, and traffic advisories. This allows ATC to monitor and manage the spacing between IFR flights and between IFR and VFR (Visual Flight Rules) traffic, as well as ensuring safe vertical and lateral separation from obstructions on the ground or in the air.

The pilot in command retains responsibility for the safe operation of the aircraft and must comply with ATC instructions. Ground control, on the other hand, is focused on managing aircraft movements on the ground at airports. Flight service stations provide flight planning services and can assist with weather information, but they do not have the authority or the responsibility to maintain separation during flight. Overall, ATC plays a central role in managing air traffic efficiently and safely in the IFR environment.