The API allows for requesting a briefing by a location defined by a latitude and longitude or an area defined by a boundary. However response differs based on what is intersecting vs nearby. See more details below.
The FAA's B4UFLY USS Performance Rules specification assumes a single location defined by a latitude and longitude.
The rules require that the airspaces that intersect the latitude and longitude define the required safety notice and authorization links to provide. Effectively, the top-level status and authorizationType are based on the intersecting notices.
The rules also require that any airspace that is within 2 nautical miles be provided as a notice to operators for additional awareness.
Airspace that intersects the latitude and longitude will be represented as a notice with a distance of 0. In the AirHub Portal UI, these are displayed in the "At this location" section. Only these notices contribute to the top-level status and authoriationType.
Airspace that does not intersect the latitude and longitude will be represented as a notice with a distance greater than 0. In the AirHub Portal UI, these are separated into a “Nearby” section.
The location briefing is best suited in cases when the area boundary is not known.
The briefing operators for a defined boundary is more advanced and goes beyond the B4UFLY ruleset. In this case, the area boundary defines the operational intent with specificity. The area boundary will intersect more airspace than a point location contributing to a more precise briefing of the area, which means the additional 2 nautical mile awareness is not needed.
All the airspaces that intersect the entire area boundary will be returned as a notice with a distance value of 0. No other notices will be returned.
Since all of the notices are intersecting, all of the notices are relevant to the top-level status and authorizationType.
The area briefing is best suited in cases when the area boundary is known, and you are looking for specific airspace briefing relevant to the safefy of flight for the entire boundary.
