What is the only north-seeking instrument in a training airplane?

The magnetic compass is the only north-seeking instrument in a training airplane because it operates based on the Earth's magnetic field. Unlike other instruments, which rely on different principles or technologies, the compass consistently aligns itself with the magnetic north. This makes it essential for navigation, as pilots can determine their heading relative to the Earth's geography.

The artificial horizon, vertical speed indicator, and altimeter do not provide directional guidance based on magnetic orientation. The artificial horizon, for instance, helps pilots understand their aircraft’s orientation relative to the horizon, the vertical speed indicator measures the rate of climb or descent, and the altimeter shows the altitude of the aircraft. These instruments serve vital functions during flight but do not seek magnetic north like the compass does. Therefore, the magnetic compass stands out as the key orientation tool specifically designed to indicate direction.