What is the opening angle on each side of the centerline for VHF airways with VORs on both ends?

For VHF airways that utilize VORs at both ends, the opening angle on each side of the centerline is designed to ensure that aircraft can reliably navigate along the airway while maintaining adequate signal coverage. The standard for this configuration is an opening angle of 4.5 degrees on each side of the centerline. This angle allows for sufficient navigational precision and safety margin to accommodate typical variations in navigation equipment and pilot technique while ensuring that the airway remains clear for aircraft navigating within the prescribed limits.

This 4.5-degree angle helps maintain the integrity of the airway structure, allowing for effective use of VOR navigation systems, which operate primarily on VHF frequencies. Knowing this angle is essential for pilots and air traffic controllers when assessing airspace design and ensuring safe flight paths.