FAA A&P Powerplant (AMP) Practice Test

How to study for the powerplant written test

Start by deciding what kind of knowledge the test is actually asking for. Powerplant questions fall into three rough classes: things that follow from how an engine works and can be reasoned out, things that are fixed by regulation, and things that are simply looked up. The first class is where nearly all the durable study value sits — why valve overlap improves cylinder filling, why detonation and pre-ignition damage an engine differently, why a compressor stalls, why a scavenge pump must have more capacity than a pressure pump, what a magneto's P-lead does and why an open one leaves the engine live. The second class is small, precise and citable: the inspection requirements of 14 CFR parts 43 and 91, who may approve an aircraft for return to service, what a maintenance record entry must contain. The third class — torque, clearances, limits, intervals — should never be memorised, and a good study plan spends its time on the first two and learns instead where the third is found.

Work the two engine families in parallel rather than in sequence. The common mistake is to spend weeks on piston engines because they came first in the course, then meet turbines in a rush at the end — or the reverse, for candidates who trained around jets. A better structure is to take one function at a time and ask how each engine family solves it. How does each get air in, and what goes wrong with the air path? How is fuel metered, and what happens when the metering drifts rich or lean? How is combustion started, and what keeps it going? How is heat carried away, and what is the first indication that it is not being? How is the engine watched from the flight deck? Studied that way, a carburetor's mixture control and a hydromechanical fuel control stop being unrelated topics and become two answers to the same question, and each makes the other easier to remember.

Give the indication-to-cause questions their own study time, because they are what the test uses to separate a candidate who has read the book from one who could work. A great many powerplant questions describe a symptom and ask what it means: a magneto drop that is too large, too small, or absent; oil pressure that is low, high, or slow to rise; a cylinder head temperature that climbs; a turbine temperature that creeps up at unchanged power; a hot start or a hung start; metal on a chip detector; a distorted fuel nozzle spray pattern; a blown discharge disc on a fire bottle. Each of these has a small set of plausible causes and a defensible first action, and the reasoning is the same reasoning you will use on the job. Practise saying out loud what the indication rules in and what it rules out before you look at the options — the answer choices are much easier once you have already formed an expectation.

Use the sections here the way you would use a syllabus, then switch to mixed practice before you test. Working one pool at a time — lubrication, then ignition and starting, then fuel metering — is the efficient way to close gaps, because a wrong answer inside a single subject tells you exactly what to reread. But the real test does not group its questions, and the skill of recognising which system a scenario belongs to is a separate skill that only mixed practice builds. So once each section is comfortable, move to the timed mock, which draws across all of them. Read the explanation on every question you get right as well as every one you get wrong: on a test written around mechanisms, a right answer reached by elimination is a gap that has not surfaced yet. Every question here appears in English, Simplified Chinese, and Spanish, so you can study a system in whichever language you think in and then confirm you know it in the language you will be tested in.