ATPL: Isogrives are lines that connect positions that have:
Domanda 334, General Navigation - ATPL - Airline Transport Pilot license
| The same grivation |
| O° magnetic dip |
| The same variation |
| The same horizontal magnetic field strength |
| The same grivation |
| O° magnetic dip |
| The same variation |
| The same horizontal magnetic field strength |
