What is the maximum tolerance allowed for an operational VOR equipment check when using a VOT?

When conducting an operational check of VOR (VHF Omnidirectional Radio Range) equipment using a VOR Test Facility (VOT), the maximum tolerance allowed is indeed plus or minus 4 degrees. This standard ensures that the VOR equipment remains within acceptable accuracy levels, which is crucial for navigation reliability.

The VOT provides a precise signal for pilots to check their VOR navigation systems. According to the regulations, if a pilot receives a VOR indication that deviates more than 4 degrees from the VOT radial, the equipment is considered out of limits, and further action is necessary to address any potential discrepancies. Maintaining this standard helps ensure that all VOR navigational aids function optimally for safe flight operations.