FAA Aircraft Dispatcher Practice Exam

What ceiling and visibility conditions define IFR?

1. Less than 1000 ft ceiling and less than 3 miles visibility

2. Less than 2000 ft ceiling and less than 5 miles visibility

3. More than 1000 ft ceiling and less than 3 miles visibility

4. Less than 1500 ft ceiling and more than 3 miles visibility

The correct answer is: Less than 1000 ft ceiling and less than 3 miles visibility

The conditions that define Instrument Flight Rules (IFR) are critical to ensuring pilots have the necessary visibility and ceiling to operate an aircraft safely in various weather situations. IFR conditions are primarily determined by low visibility and low ceiling situations. In this context, the correct answer specifies that IFR is defined by a ceiling of less than 1,000 feet along with visibility of less than 3 statute miles. This combination indicates restricted flight conditions, where pilots may no longer be able to navigate visually and must rely on instruments. This definition is consistent with regulations set forth by aviation authorities, which stipulate the thresholds for visual flight rules (VFR) versus IFR. The other options reflect conditions that allow for more visibility or higher ceilings than what is established for IFR, meaning that those conditions would generally allow for flight under VFR instead. Understanding these critical thresholds is vital for safety in aviation operations, ensuring that dispatchers, pilots, and other personnel know when additional instrument navigation is required due to subpar weather conditions.