How many miles of lateral separation is provided for an aircraft on an established airway or route within 51 miles from the NAVAID?

The correct response indicates that an aircraft on an established airway or route within 51 miles from the NAVAID is provided with 4 miles of lateral separation on either side. This lateral separation is a crucial aspect of air traffic control because it helps to ensure safe distances between aircraft, minimizing the risk of collisions during flight operations.

In controlled airspace, especially near navigational aids (NAVAIDs), maintaining sufficient lateral separation is necessary for safe navigation and traffic management. The standards set by the Federal Aviation Administration (FAA) dictate that within a certain proximity to NAVAIDs, this specific lateral separation distance is adhered to in order to accommodate potential navigation inaccuracies or deviations from the intended flight path.

The other distances provided in the options are not in accordance with the FAA regulations for lateral separation near NAVAIDs. Thus, the standard of 4 miles on either side serves as the established guideline, creating safe buffers for aircraft operating in these critical areas of airspace.