Returns the number of CPR longitude zones (NL) at a given latitude, per ICAO Annex 10 Vol. IV / RTCA DO-260B SS A.1.7.2. NL is 1-59, monotone non-increasing in absolute latitude: 59 at the equator, 2 at +-87 deg, 1 beyond +-87 deg.
Latitude in decimal degrees.
The number of longitude zones, 1-59.
Returns the number of CPR longitude zones (NL) at a given latitude, per ICAO Annex 10 Vol. IV / RTCA DO-260B SS A.1.7.2. NL is 1-59, monotone non-increasing in absolute latitude: 59 at the equator, 2 at +-87 deg, 1 beyond +-87 deg.