What does a malfunctioning altimeter affect during flight?

A malfunctioning altimeter directly impacts altitude awareness, which is crucial for safe flight operations. The altimeter measures the aircraft's altitude above sea level by detecting changes in atmospheric pressure. If the altimeter is not functioning properly, the pilot may be unaware of the aircraft's true altitude, leading to potential hazards such as flying at incorrect altitudes, which can increase the risk of mid-air collisions or terrain collisions.

Maintaining accurate altitude awareness is vital for complying with airspace regulations, conducting safe takeoffs and landings, and ensuring proper separation from other aircraft. Ultimately, a malfunctioning altimeter can compromise the safety of the flight, making altitude awareness the most critical aspect affected.