How far can a Non-Directional Beacon (NDB) transmit signals effectively?

A Non-Directional Beacon (NDB) typically transmits signals effectively up to 25 nautical miles under normal operating conditions. This range can vary based on several factors, including the type of NDB, atmospheric conditions, and the specific terrain surrounding the beacon.

The primary function of an NDB is to provide navigational aid to pilots by allowing them to determine their position relative to the beacon. Within the effective range, pilots use ADF (Automatic Direction Finder) equipment to receive signals and navigate towards or away from the NDB. The maximum range of 25 nautical miles is ideal for medium-range navigation and helps ensure that pilots can maintain adequate situational awareness while flying.

In real-world applications, the effectiveness of an NDB signal can diminish due to obstacles such as mountains, large structures, or adverse weather conditions, which might limit the actual usable range. Nonetheless, for training and theoretical purposes, the effective transmission range of 25 nautical miles is generally accepted for NDBs.