What type of signal does an NDB emit for aircraft navigation?

An NDB, or Non-Directional Beacon, emits radio signals for aircraft navigation. These signals are typically in the medium frequency range and are transmitted in all directions around the beacon, allowing pilots to use the equipment in their aircraft to determine their bearing relative to the NDB.

When an aircraft is within range of the NDB signal, the pilot can tune into the specific frequency and track their position relative to the beacon. This is vital for navigation, especially in poor visibility conditions or in areas where visual landmarks may be scarce.

The other options do not align with the operational purpose of an NDB. Sound signals are primarily used in audio communication rather than navigation, while laser signals are not typically employed in aviation navigation but rather in other specialized applications. Magnetic signals are more associated with compass navigation rather than the radio signals emitted by an NDB.