What would likely happen if an aircraft's static system had leakage issues?

When an aircraft's static system experiences leakage issues, it compromises the integrity of the air pressure readings that are essential for determining altitude and vertical speed. The static pressure system feeds information to several instruments, including the altimeter, vertical speed indicator, and sometimes the airspeed indicator if it uses static pressure for correction.

If there's a leak, the static pressure may not be accurately transmitted to these instruments, leading to erroneous readings. For example, an airspeed indicator that relies on both dynamic and static pressure could indicate incorrect airspeed, either too high or too low, because the static pressure it receives is not reflective of the actual atmospheric conditions.

This inconsistency can create significant challenges in flying, such as misjudging altitude during critical phases of flight, affecting the pilot's decision-making and overall flight safety. Therefore, leakage in the static system directly impacts airspeed indications, making it the most relevant concern among the provided choices.