FAA Aviation Mechanic Airframe (AMA)Landing Gear SystemsEasy
A technician is inspecting a nose landing gear switch that signals the aircraft's weight is on the wheels. This switch is most commonly known as the
- Asquat switch
- Bsequence valve
- Canti-skid transducer
- Dtorque link sensor
Show answer & explanationAnswer & explanation
Correct answer: A. squat switch
The squat switch (weight-on-wheels switch) senses strut compression to indicate ground versus flight condition, controlling systems such as gear retraction lockout, spoiler arming, and cabin pressurization outflow.
Why the other options are wrong
- B. Sequence valves control hydraulic flow timing during retraction, not weight sensing.
- C. Anti-skid transducers measure wheel speed for braking, not weight.
- D. Torque links transmit steering forces, not weight sensing.
Squat Switch
A weight-on-wheels switch mounted on the landing gear strut that signals whether the aircraft is on the ground or in flight.
- Activated by strut compression/extension
- Prevents inadvertent gear retraction on ground
- Also used for spoiler, pressurization, and warning system logic
Memory trick: Squat = 'squished' strut tells the plane it's on the ground