When verifying the TACAN at a designated ground checkpoint, what is the allowable error for the distance measurement?

The allowable error for the distance measurement when verifying the TACAN (Tactical Air Navigation) at a designated ground checkpoint is indeed 1/2 mile or 3 percent of the distance. This standard ensures that the measurements provided by the TACAN system are accurate and reliable for navigation purposes. Adhering to this specification allows pilots to maintain confidence in the data they receive, which is critical for flight safety.

When considering distance-related operations, both absolute and relative errors matter. The 1/2 mile option sets a clear limit on the maximum acceptable deviation, while the 3 percent figure ensures that for longer distances, the margin for error remains proportional. This dual threshold accounts for varying distances and ensures that errors do not become excessive as distance increases.

Other options, while they express acceptable ranges, do not align with the established standard for TACAN distance monitoring.