Instrument Rating Checkride Practice Test

Which of the following is a requirement for the magnetic compass during taxi?

1. It must show the correct heading

2. It must be calibrated to the local time

3. It must be adjusted for magnetic variation

4. It must have a separate power supply

The correct answer is: It must show the correct heading

The requirement for the magnetic compass during taxiing is that it must show the correct heading. This is crucial because pilots rely on the compass for navigating and aligning the aircraft correctly on the ground, especially when taxiing to the runway. While the magnetic compass may not be as accurate at low speeds or in a rapid-turn environment, it should still reflect an accurate heading that the pilot can use for directional awareness. The other options reflect aspects of compass or instrument requirements that are not directly related to the taxiing phase. Calibration to local time is not applicable to a magnetic compass, as time does not influence how a compass operates. Adjusting for magnetic variation is typically done before departure to ensure the heading indicated matches the true course, but this is more critical for flight rather than during taxi. Similarly, a magnetic compass does not require a power supply, as it operates purely on the principles of magnetism.