In some instances Mandatory Broadcast Zones are located immediately below controlled airspace. If the area of the MBZ spans multiple CTAs with different lower limits then the upper limit of the MBZ is defined as the lower limit of each adjacent CTA. This is extremely difficult for the airspce converter to parse.
To avoid overly complicated logic the airspace converter makes an approximation. It takes the conservative approach of making the upper limit of the MBZ equal to the highest lower limit of the adjacent CTAs. The nett affect is that the upper surface of the MBZ extends slightly into some of the CTAs, so this is not expected to have any significant affect on flying activities.
MBZs affected by this issue are: NZB 175, NZB 273 and NZB 371.
In some instances a General Aviation Area spans multiple CTAs with different lower limits. In that case the lower limit of the GAA is defined as the lower limit of each intersecting CTA. This is extremely difficult for the airspce converter to parse.
To avoid overly complicated logic the airspace converter makes an approximation. It takes the conservative approach of making the lower limit of the GAA equal to the lowest lower limit of the intersecting CTAs. The nett affect is that the lower surface of the GAA extends below the lower surface some of the CTAs. Given that in most instances the GAA will be either automatically open, or have been manually opened, this is not expected to have any significant affect on flying activities.
GAAs affected by this issue are: NZG 357, NZG 358, NZG 370, NZG 852 and NZG 976.