PLT273: Hydraulic Systems
What code PLT273 covers, why the FAA tests it, and how to study Hydraulic Systems before your checkride.
Recall hydraulic systems - components / operating principles / characteristics
What this means for your checkride
A hydraulic system uses an incompressible fluid under pressure to move things that need force: retractable landing gear, flaps, and brakes on many airplanes. A pump pressurizes the fluid and valves direct it to actuators. Because fluid does not compress, it transmits force efficiently, but a leak or air in the lines makes it spongy or inoperative.
Hydraulics operate gear, flaps, and brakes, so the FAA tests the components, how they work, and the signs of a leak or failure.
Pilots dismiss a soft brake pedal as normal wear. A spongy pedal usually means air or a leak in the hydraulic line, which can fail completely under heavy braking.
Where to study it
A code on your test report is an area of deficiency. An authorized instructor must review it with you and endorse that review before you take the practical test, and the examiner may revisit it during the oral. Study it until you can explain it out loud, not just recognize the answer.