When checking TACAN at a designated ground checkpoint, what is the allowable error?

When checking TACAN (Tactical Air Navigation), it's important to verify that the system meets the required accuracy standards. The allowable error when checking TACAN at a designated ground checkpoint is indeed specified as 1/2 mile or 3 percent of the distance from the TACAN station being checked.

This standard is in place to ensure the reliability and precision of navigational information that pilots depend on for safe operations. By maintaining a tolerance of 1/2 mile or 3 percent, it helps ensure that navigational aids provide a level of accuracy suitable for military operations where precision is crucial.

The other options present allowable error thresholds that exceed the established standards set for TACAN checks, making them incorrect in this context.