A VOR test facility (VOT) is a ground facility used to check VOR receiver accuracy. Some VOTs are available airborne, others ground use only. Which statement is true?

• A. VOTs are only ground-based.
• B. Some VOTs are airborne, some are ground-use only.
• C. VOTs are never used in flight.
• D. VOTs are used to tune VOR frequencies.

Answer: (B)

VOTs provide a known VOR reference signal that lets you verify that the VOR receiver and CDI indicate the correct course. Because some VOTs are installed in aircraft and others are ground-based, checks can be performed either in flight or on the ground. That makes the statement true: there are airborne VOTs as well as ground-use-only ones. VOTs aren’t used to tune VOR frequencies; they’re used to test the accuracy of the VOR reception and indication, serving as a reference signal for calibration in either flight or ground scenarios.