What is the primary function of the squat switch in an aircraft?

The primary function of the squat switch in an aircraft is to inhibit the stall horn on the ground. This device senses whether the aircraft is on the ground or in flight. When the aircraft is on the ground, the squat switch prevents the stall warning horn from activating while the aircraft is taxiing or stationary, which is crucial to avoid unnecessary alarm sounds that could distract the pilot. This allows pilots to focus on ground operations without having to deal with potentially confusing stall warnings when they are not in a flight-critical phase.

In contrast, the other options are unrelated to the squat switch's intended function. Navigation lights are regulated by the aircraft's electrical system independently of whether the aircraft is on the ground or in flight. Cabin pressure management is controlled by different systems and sensors that monitor the aircraft's altitude and pressurization dynamics. Fuel distribution is managed by fuel system components and valves, not a squat switch.