What does IFR stand for in aviation?

In aviation, the acronym IFR stands for Instrument Flight Rules. This refers to a set of regulations under which a pilot operates an aircraft in weather conditions generally poor enough to require reliance on instruments for navigation and control, rather than visual references. IFR procedures are essential for ensuring safety in low visibility situations, allowing pilots to navigate and control their aircraft safely through the use of instruments.

While the other options might seem plausible at first glance, none of them accurately captures the meaning of IFR in the context of aviation. International Flight Regulations could refer to a broader set of guidelines but does not specifically address the context of pilots navigating using instruments. In-flight Radio Frequency pertains to communications in the air but does not describe the operational rules under which aircraft are flown. Internal Flight Record does not have relevance to flight operations or regulations, making Instrument Flight Rules the only correct interpretation in this scenario.