Hangar Prep

FAA Mechanic General (AMG) Knowledge Test, Practice Exams

The Aviation Mechanic General written test (AMG): 60 scored questions, 2 hours, 70% to pass. Original questions written to the FAA-S-ACS-1 blueprint and grounded in FAA-H-8083-30B and 14 CFR, with cited explanations.
Content last updated 3 July 2026

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The real test requires 70% to pass. Each knowledge area is scored separately here so you know exactly where you stand.

Unlock the full question bank

The free sample gives you about two exams' worth of questions per knowledge area. The full bank covers every ACS knowledge area in depth, with source-cited explanations. $49, one time, lifetime access on up to 3 devices — all three tests (General, Airframe, Powerplant) included.

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Frequently asked questions

How is the FAA Mechanic General (AMG) Knowledge Test structured?

The real Aviation Mechanic - General written test has 60 multiple-choice questions (3 options each), a 2-hour time limit, and requires 70% to pass. Questions are drawn across 12 knowledge areas per the FAA-S-ACS-1 blueprint; this bank mirrors those areas and weights.

What score do I need to pass?

70 percent. Practice each knowledge area to that level, then run the full exam simulation before your test date.

Are these real FAA exam questions?

The live test bank is not published. Our questions include the FAA's own published sample questions plus original questions written to the ACS blueprint and grounded in the FAA handbooks (FAA-H-8083-30B/31B/32B) and 14 CFR, with the source cited in each explanation.

How many practice questions are included?

The full Aviation Mechanic - General bank contains 375 questions with explanations. The free sample gives you roughly two exams' worth per knowledge area.

Do I need all three tests?

A full A&P certificate requires General, Airframe, and Powerplant written tests (plus oral & practical). One Hangar Prep purchase covers all three, for life.

What does access cost?

$49, one time, for lifetime access to all three tests and everything we add later. No subscription.

Can I use it on more than one device?

Yes. One purchase works on up to 3 of your devices. Your progress is saved on each device.

Do I need to create an account?

No. The practice tests run in your browser with no signup. Your score history is saved on your own device.

Sample FAA Mechanic General (AMG) Knowledge Test practice questions

A selection of free questions with answers and explanations. Use the interactive modules above for timed, scored drills.

What is the value of the square root of 64 plus 4 squared?

  1. 24 ✓
  2. 80
  3. 20

Why: Square root of 64 is 8; 4 squared is 16; 8 + 16 = 24. FAA-H-8083-30B ch.3 (powers and roots).

Flareless (MS) fittings differ from AN flare fittings in that flareless fittings

  1. seal by a sleeve biting into the tube, so the tube end is not flared. ✓
  2. require a double flare to be formed on all tube sizes before the sleeve is installed
  3. can only be used on low-pressure instrument air lines.

Why: MS flareless fittings use a presetting sleeve that bites into the tube - no flare is formed on the tube end. FAA-H-8083-30B ch.9.

An aircraft burns 105 gallons of fuel during a 3.5-hour flight. What is the average fuel consumption?

  1. 30 gallons per hour ✓
  2. 33 gallons per hour
  3. 27 gallons per hour

Why: 105 gallons / 3.5 hours = 30 gallons per hour. FAA-H-8083-30B ch.3 (division).

Show more sample questions with answers & explanations

A sheet metal repair requires 12 rivets for each of 14 wing ribs, plus 25 additional rivets for the doubler. How many rivets are required in total?

  1. 193 ✓
  2. 183
  3. 203

Why: 12 rivets x 14 ribs = 168, plus 25 for the doubler = 193 rivets. FAA-H-8083-30B ch.3 (multiplication and addition of whole numbers).

14 CFR part 65 contains regulations regarding the certification of

  1. pilots, flight instructors, and ground instructors.
  2. airmen other than flight crewmembers. ✓
  3. flight crewmembers other than pilots.

Why: 14 CFR part 65 contains the certification regulations for airmen other than flight crewmembers. 14 CFR part 65.

How many personnel are required to service an aircraft with gaseous oxygen?

  1. Two: one at the servicing control valves and one observing the aircraft system pressure ✓
  2. One qualified technician, provided the servicing cart has an automatic shutoff regulator
  3. Three: one at the cart, one at the aircraft valve, and one dedicated fireguard standing by

Why: Two personnel are required to service an aircraft with gaseous oxygen: one at the control valves and one observing the pressure in the aircraft system, with communication between them. FAA-H-8083-30B ch.1.

Approximately what percentage of maintenance-related errors is estimated to be caused by distractions?

  1. About 15 percent ✓
  2. About 40 percent
  3. About 5 percent

Why: It is estimated that 15 percent of maintenance-related errors are caused by distractions; a good practice is to go back three steps in the procedure when work resumes after a distraction. FAA-H-8083-30B ch.14.

Magnetic particle inspection can be used on which materials, and what must be done after the test?

  1. Ferromagnetic materials only; the part must be demagnetized after the test ✓
  2. Any electrically conductive material; the part must be re-anodized after the test
  3. Nonporous nonmetals and metals alike; the part must be re-primed after the test

Why: Magnetic particle inspection works on ferromagnetic materials only, detects surface and subsurface discontinuities, and the part must be demagnetized after the test. FAA-H-8083-30B ch.10.

A supplemental type certificate (STC) is issued when

  1. a person receives FAA approval for a major change to a type design not great enough to require a new type certificate. ✓
  2. an aircraft passes its annual inspection with no discrepancies listed by the inspector on the record entry.
  3. a manufacturer publishes a new revision of its maintenance manual or illustrated parts catalog for the model.

Why: An STC approves a major modification of the type design; TCDSs and STCs are available through FAA databases and must be consulted for modified aircraft.

What type of drawing line consists of alternating long and short lines?

  1. Dimension.
  2. Center. ✓
  3. Hidden.

Why: A center line consists of alternating long and short dashes. FAA-H-8083-30B ch.4.

What is the MEDA process, and who developed it?

  1. The Maintenance Error Decision Aid, developed by Boeing to investigate errors and find root causes rather than assign blame ✓
  2. The Maintenance Event Discrepancy Analysis, a program developed by the FAA to track and trend recurring component failures across a fleet
  3. The Mechanic Error Detection Audit, developed by Transport Canada to certify and annually requalify aircraft inspection personnel

Why: MEDA (Maintenance Error Decision Aid) was developed by Boeing; its goal is to investigate errors, understand root causes, and prevent accidents, instead of placing blame on the maintenance personnel. FAA-H-8083-30B ch.14.

Fretting corrosion between two mating surfaces is also known by what name, and is identified on a rivet how?

  1. False brinelling; identified as a smoking rivet with a black ring around the rivet ✓
  2. Filiform corrosion; identified by worm-like traces radiating from the rivet head
  3. Galvanic corrosion; identified by a blue-green powdery deposit around the rivet

Why: Fretting corrosion occurs when mating surfaces at rest undergo slight relative motion; it has been called false brinelling, and the common example is the smoking rivet, identified by a black ring around the rivet. FAA-H-8083-30B ch.8.

When an aircraft is sold domestically, the Airworthiness Certificate

  1. must be surrendered to the local Flight Standards District Office.
  2. becomes invalid until the new owner makes application for a new Airworthiness Certificate.
  3. is transferred with the aircraft at the time of sale. ✓

Why: When an aircraft is sold domestically, the Airworthiness Certificate is transferred with the aircraft at the time of sale. FAA-H-8083-30B ch.2.

When calculating the new weight and balance for an aircraft, what is used to determine the operating CG range?

  1. The data plate.
  2. The type certificate data sheets. ✓
  3. The pilot information manual.

Why: The operating CG range used in weight-and-balance calculations is obtained from the Type Certificate Data Sheets. FAA-H-8083-30B ch.6.

According to Faraday's law, the voltage induced in a coil is proportional to

  1. the rate at which magnetic flux through the coil changes. ✓
  2. the resistance of the coil windings.
  3. the steady strength of the magnetic field alone.

Why: Faraday's law: induced emf depends on the rate of change of flux linking the coil - the basis of generator action. FAA-H-8083-30B ch.12.

What is the standard position for an aircraft taxi signalman relative to the aircraft?

  1. Slightly ahead of and in line with the aircraft's left wingtip, within the pilot's field of vision ✓
  2. Directly in front of the nose of the aircraft, far enough back to clear the propeller arc
  3. Slightly behind and in line with the aircraft's right wingtip to watch the tail clearance

Why: The standard position for a signalman is slightly ahead of and in line with the aircraft's left wingtip, staying far enough ahead to remain in the pilot's field of vision. FAA-H-8083-30B ch.1.

What type of line is normally used in a drawing or blueprint that indicates invisible edges or contours?

  1. Medium weight short dashes evenly spaced. ✓
  2. Medium weight very short dashes evenly spaced.
  3. Thin weight one long and two short dashes evenly spaced.

Why: Invisible (hidden) edges or contours are shown with a medium-weight line of short dashes evenly spaced. FAA-H-8083-30B ch.4.

If a part to be inspected for surface defects is made of a magnetic material, which inspection method is generally recommended?

  1. Magnetic particle inspection ✓
  2. Liquid penetrant inspection
  3. Ultrasonic inspection

Why: If the part in question is made of a magnetic material, magnetic particle inspection is generally recommended over penetrant inspection. FAA-H-8083-30B ch.10.

Charles' law states that a gas expands and contracts in what relationship to absolute temperature, provided pressure is constant?

  1. In direct proportion to the change in absolute temperature ✓
  2. In inverse proportion to the change in absolute temperature
  3. In direct proportion to the square root of the absolute temperature

Why: Charles' law: all gases expand and contract in direct proportion to the change in absolute temperature, provided pressure is held constant (V1T2 = V2T1). FAA-H-8083-30B ch.5.

The purpose of a voltage regulator in an aircraft generator system is to

  1. hold the generator output voltage constant as load and speed vary. ✓
  2. increase the generator output as the battery discharges.
  3. convert the generator's AC output to DC.

Why: The regulator adjusts field current so output voltage stays constant despite changing engine speed and electrical load. FAA-H-8083-30B ch.12.

Examples of units used in the conventional (U.S. or English) measurement include

  1. inch, meter, gram.
  2. inch, kilo, liter.
  3. inch, ounce, pounds. ✓

Why: Conventional (U.S./English) measurement units include the inch, ounce, and pound. FAA-H-8083-30B ch.3.

What is the correct grounding/bonding sequence when fueling an aircraft from a fuel truck?

  1. Ground the aircraft, then ground the truck, then bond the two together ✓
  2. Bond the truck to the aircraft first, then ground the aircraft, then ground the truck
  3. Ground the truck, then bond it to the aircraft, and leave the aircraft itself ungrounded

Why: Ground the aircraft and then ground the truck; next, ground or bond them together by running a connecting wire between the aircraft and the fuel truck. FAA-H-8083-30B ch.1.

In a sectional view drawing, what sections illustrate particular parts of an object?

  1. Removed. ✓
  2. Revolved.
  3. Half.

Why: Removed sections illustrate particular parts of an object, drawn outside the main view. FAA-H-8083-30B ch.4.

The 'Environment' element of the PEAR model addresses which two environments in aviation maintenance?

  1. The physical workplace and the organizational environment within the company ✓
  2. The indoor hangar environment and the outdoor flight-line weather environment
  3. The regulatory environment and the economic environment of the airline industry

Why: A human factors program must address at least two environments: the physical workplace (ramp, hangar, shop) and the organizational environment that exists within the company. FAA-H-8083-30B ch.14.

A handle-length extension (cheater bar) must never be used on

  1. a flexible beam-type torque wrench. ✓
  2. a rigid-frame click-type torque wrench.
  3. any wrench used below 100 inch-pounds.

Why: The handbook cautions against handle extensions on flexible beam-type wrenches; on other types a handle extension alone does not change the reading. FAA-H-8083-30B ch.7.

When installing a flexible hose assembly, the hose should be

  1. installed with about 5 to 8 percent slack, never taut. ✓
  2. stretched taut between the fittings so that vibration cannot whip the hose
  3. twisted as needed to align the fittings.

Why: Hose shortens under pressure, so 5-8% slack is required; hose must never be installed twisted or taut. FAA-H-8083-30B ch.9.

The capacity of an aircraft storage battery is rated in

  1. ampere-hours. ✓
  2. volts.
  3. watts.

Why: Battery capacity - how much current it can deliver for how long - is expressed in ampere-hours. FAA-H-8083-30B ch.12.

Which of the following tools is best to use when cutting soft aluminum tubing?

  1. Hand operated wheel-type tubing cutter. ✓
  2. Angle grinder with cut-off wheel.
  3. Circular-saw equipped with an abrasive cutting wheel.

Why: A hand-operated wheel-type tubing cutter is best for cutting soft aluminum tubing. FAA-H-8083-30B ch.9.

From the control tower, a flashing green light signal directed at a taxiing aircraft means what?

  1. Cleared to taxi ✓
  2. Return to starting point
  3. Taxi clear of the runway in use

Why: Standard taxi light signals: flashing green means cleared to taxi. FAA-H-8083-30B ch.1 (Figure 1-22).

Alclad aluminum sheet is aluminum alloy

  1. coated with a thin layer of pure aluminum for corrosion protection. ✓
  2. that has been anodized a distinctive blue color.
  3. clad with stainless steel on one side for wear resistance.

Why: Alclad carries pure-aluminum surface layers whose natural oxide protects the stronger but less corrosion-resistant alloy core. FAA-H-8083-30B ch.7.