Instrument Flight Rules (IFR) Practice Exam 2026 – The All-in-One Guide to Master Your IFR Certification!

The maximum permissible variation between two VOR systems when checked against each other in flight is plus or minus 4 degrees when both systems are set to identical radials of a VOR. This standard ensures that pilots receive reliable and accurate navigation information while in flight, which is vital for maintaining situational awareness and ensuring safety.

When conducting VOR checks, pilots are expected to compare the indications from two VOR receivers. If both systems are tuned to the same VOR and are indicating different bearings, the difference should not exceed 4 degrees. This requirement helps ensure that both navigation aids are functioning correctly and that their readings are consistent, allowing for precise navigation and course tracking.

This limit supports effective air traffic management by ensuring pilots can trust their instruments when navigating through controlled airspace or during critical phases of flight.