Commercial Checkride Practice Test

The altimeter is essential for monitoring aircraft altitude during VFR (Visual Flight Rules) day flight because it provides crucial information about the aircraft's height above sea level. This instrument measures atmospheric pressure and translates it into an altitude reading. Pilots need to maintain specific altitudes for safe navigation and to avoid obstacles and other aircraft, making the altimeter indispensable for situational awareness and compliance with airspace regulations.

During VFR flight, pilots often rely on visual references outside the cockpit, but altitude management is critical to ensure safety. The altimeter helps pilots maintain a proper flight level in relation to terrain and weather conditions. Accurate altitude readings are also crucial during climb and descent phases, ensuring that the aircraft remains in controlled airspace and avoids conflicts with other traffic.

The other instruments listed, such as the oil temperature gauge, fuel gauge, and temperature gauge, do not provide information about altitude and are related to the performance and status of the aircraft's systems rather than vertical positioning.