What is the risk of operating an aircraft with an unserviceable pitot-static system?

Operating an aircraft with an unserviceable pitot-static system poses a significant risk of incorrect altitude readings. The pitot-static system is essential for providing accurate information about the aircraft's airspeed, altitude, and vertical speed. If this system is malfunctioning, the altimeter may display erroneous altitude data, which can lead to serious issues such as flying at incorrect altitudes relative to other aircraft or terrain, potentially resulting in mid-air collisions or controlled flight into terrain (CFIT).

The integrity of the pitot-static system is crucial, as it relies on the differential pressure from the outside air to accurately determine altitude. When there are faults in this system, it undermines the pilot's ability to trust the information displayed on the cockpit instruments. This can directly impact flight safety, as altitude reporting is critical for maintaining safe separation from other aircraft and terrain, especially in various phases of flight including climb, cruise, and descent.

In summary, the risk stemming from an unserviceable pitot-static system centers around compromised altitude readings, which can severely affect flight safety and operational decision-making.