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FAA Aviation Mechanic - General (AMG) study materials
FAA Aviation Mechanic - General (AMG) study resources

FAA Aviation Mechanic - General (AMG) practice questions

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Question 1Basic Electricity

The unit of measurement for electrical resistance is the

  1. ohm Correct answer.
  2. watt
  3. ampere
  4. volt

Explanation

Resistance is the opposition to current flow and is measured in ohms. Each electrical quantity has its own unit: current in amperes, electromotive force in volts, and power in watts.

Question 2Basic Electricity

Which expression correctly gives the voltage in a circuit when current and resistance are known?

  1. E = I × R Correct answer.
  2. E = I / R
  3. E = R / I
  4. E = P × I

Explanation

Ohm's law states that voltage equals current multiplied by resistance, written E = I × R. Dividing rather than multiplying, or mixing in power, gives a result that is not in volts.

Question 3Basic Electricity

The rate of electron flow through a conductor is measured in

  1. ohms
  2. watts
  3. amperes Correct answer.
  4. volts

Explanation

Current is the movement of electrons and is expressed in amperes, where one ampere is one coulomb per second. Volts describe the push behind the electrons and ohms describe the opposition to them.

Question 4Basic Electricity

In a series circuit containing three unequal resistors, the current is

  1. the same through every resistor Correct answer.
  2. least through the smallest resistor
  3. greatest through the largest resistor
  4. the sum of the currents through each resistor

Explanation

A series circuit provides only one path, so the same electrons pass through every component in turn and the current is identical at all points. The voltage divides across the resistors in proportion to their resistance.

Question 5Basic Electricity

The electrical pressure that causes current to flow in a circuit is called

  1. resistance
  2. power
  3. current
  4. voltage Correct answer.

Explanation

Voltage is the difference in potential that pushes electrons through a conductor, sometimes called electromotive force. Resistance opposes the flow, current is the flow itself, and power is the rate of energy use.

Question 6Basic Electricity

In a DC circuit, electrical power is calculated as

  1. voltage × current Correct answer.
  2. current ÷ resistance
  3. resistance × voltage
  4. voltage ÷ current

Explanation

Power in watts equals voltage times current, P = E × I. Any combination that divides one quantity by another yields units that are not watts.

Question 7Basic Electricity

Three resistors of 10 ohms, 20 ohms, and 30 ohms are connected in series. What is the total resistance?

  1. 60 ohms Correct answer.
  2. 600 ohms
  3. 20 ohms
  4. 6.0 ohms

Explanation

In a series circuit the total resistance is the simple sum of the individual resistances: 10 + 20 + 30 = 60 ohms. The reciprocal formula is used only for parallel branches.

Question 8Basic Electricity

Two 6-ohm resistors are connected in parallel. What is their combined resistance?

  1. 6 ohms
  2. 3 ohms Correct answer.
  3. 12 ohms
  4. 0.33 ohm

Explanation

For two equal resistors in parallel, the total is half of one value: 6 ÷ 2 = 3 ohms. The general method is to add the reciprocals of the branch resistances and invert the result.

Question 9Basic Electricity

A 12-volt source is connected across a 4-ohm resistor. What current flows?

  1. 16 amperes
  2. 0.33 ampere
  3. 3 amperes Correct answer.
  4. 48 amperes

Explanation

Ohm's law gives current as voltage divided by resistance: 12 ÷ 4 = 3 amperes. Multiplying the two values instead of dividing is a common error.

Question 10Basic Electricity

A 24-volt circuit draws 2 amperes of current. How much power is consumed?

  1. 48 watts Correct answer.
  2. 12 watts
  3. 0.083 watt
  4. 26 watts

Explanation

Power equals voltage multiplied by current: 24 × 2 = 48 watts. This relationship holds for any DC circuit and is also the basis for the I-squared-R form of the power equation.

Question 11Basic Electricity

A voltmeter is used to measure the voltage drop across a component and is connected

  1. in series with the negative lead
  2. in series with the load
  3. in parallel with the load Correct answer.
  4. in series with the circuit breaker

Explanation

Voltage is a difference in potential between two points, so the meter must be placed across the component with its two leads touching either side. Connecting it in the current path would add its high resistance to the circuit.

Question 12Basic Electricity

To measure the current flowing through a circuit, an ammeter is connected

  1. in series with the circuit Correct answer.
  2. across the power source
  3. in parallel with the load
  4. parallel to the circuit breaker

Explanation

An ammeter must carry the current it is measuring, so it is placed in the current path and has very low internal resistance. Connecting it across a voltage source would create a short circuit.

Question 13Basic Electricity

Before a wire is checked for continuity with an ohmmeter, the circuit must be

  1. dead and disconnected Correct answer.
  2. connected to a live bus
  3. carrying its normal load current
  4. energized at rated voltage

Explanation

An ohmmeter supplies its own small current to measure resistance, so any external voltage will corrupt the reading and can damage the meter. The component must also be isolated so parallel paths do not affect the measurement.

Question 14Basic Electricity

An alternator produces alternating current at a frequency of 400 hertz. How many times per second does the current reverse direction?

  1. 1,600 times per second
  2. 800 times per second Correct answer.
  3. 400 times per second
  4. 200 times per second

Explanation

Frequency in hertz is the number of complete cycles per second, and each cycle contains two reversals of direction, one at the end of the positive half and one at the end of the negative half. Thus 400 cycles per second produce 800 reversals per second.

Question 15Basic Electricity

The property of a coil that opposes any change in the current flowing through it is called

  1. inductance Correct answer.
  2. capacitance
  3. conductance
  4. impedance

Explanation

Inductance is the characteristic of a coil that resists a change in current by producing a counter-electromotive force. Capacitance opposes a change in voltage, while impedance is the total opposition to alternating current.

Question 16Basic Electricity

A 24-volt source is connected across a 40-ohm and a 60-ohm resistor in series. What is the voltage drop across the 40-ohm resistor?

  1. 6 volts
  2. 14.4 volts
  3. 9.6 volts Correct answer.
  4. 24 volts

Explanation

Total resistance is 100 ohms, so current is 24 ÷ 100 = 0.24 ampere. The drop across the 40-ohm resistor is 0.24 × 40 = 9.6 volts, and the remaining 14.4 volts appears across the 60-ohm resistor.

Question 17Basic Electricity

Three 10-microfarad capacitors are connected in parallel. What is the total capacitance?

  1. 3.33 microfarads
  2. 10 microfarads
  3. 0.33 microfarad
  4. 30 microfarads Correct answer.

Explanation

Capacitors in parallel add directly because each one sees the same voltage and the stored charge accumulates. This is the reverse of how resistors combine in parallel.

Question 18Basic Electricity

Two resistors of different values are connected in parallel across a battery. Which statement about the currents is true?

  1. The larger resistor carries more current
  2. Current divides equally regardless of resistance
  3. The smaller resistor carries more current Correct answer.
  4. Both resistors carry equal current

Explanation

Each parallel branch has the full source voltage across it, so by Ohm's law the branch with the least resistance draws the most current. Total current is the sum of the branch currents.

Question 19Basic Electricity

A transformer has 100 turns on its primary winding and 500 turns on its secondary. If 12 volts AC is applied to the primary, what voltage appears at the secondary?

  1. 60 volts Correct answer.
  2. 12 volts
  3. 2.4 volts
  4. 6,000 volts

Explanation

The voltage ratio equals the turns ratio: 500 ÷ 100 = 5, so the secondary voltage is 12 × 5 = 60 volts. A step-up transformer raises voltage while lowering current in the same proportion.

Question 20Aircraft Drawings

Which information is normally found in the title block of an aircraft drawing?

  1. The empty weight and center of gravity
  2. The torque values for each fastener shown
  3. The drawing number, scale, and revision date Correct answer.
  4. The part's purchase price and supplier

Explanation

The title block is the identification area of a drawing. It normally carries the drawing number, title, scale, date, company name, and approval signatures, along with the current revision status. Other data such as torque values or weight and balance are handled in notes, specifications, or separate documents.

Question 21Aircraft Drawings

What is the purpose of zone numbers printed along the border of a large aircraft drawing?

  1. To specify the tolerance allowed on every dimension shown
  2. To show the order in which parts are assembled
  3. To help locate a particular area of the drawing Correct answer.
  4. To identify the manufacturer of each component

Explanation

Large drawings are divided into a grid of zones lettered and numbered around the border. A note or parts list can then refer to a zone so the reader can find the area quickly. Zone numbers are a locating aid only and carry no dimensional or assembly meaning.

Question 22Aircraft Drawings

In an orthographic projection drawing, how are hidden edges and outlines represented?

  1. By long-short-long centerlines
  2. By short evenly spaced dashes Correct answer.
  3. By thin lines with arrowheads
  4. By solid heavy lines

Explanation

Hidden edges are drawn with short, evenly spaced dashes so the outline is visible but clearly distinguished from visible edges. Visible outlines use solid heavy lines. The dashed convention allows internal features to be shown without a section view.

Question 23Aircraft Drawings

How are centerlines drawn on an aircraft drawing?

  1. As alternating long and short dashes Correct answer.
  2. As short evenly spaced dashes
  3. As thin lines broken by short hatch marks
  4. As continuous heavy solid lines

Explanation

Centerlines use a repeating pattern of one long dash followed by a short dash. They mark axes of symmetry, hole centers, and cylindrical parts. The pattern distinguishes them from hidden lines, which are evenly spaced short dashes.

Question 24Aircraft Drawings

A drawing is marked 'half scale.' What does this indicate?

  1. The dimensions are one-half of the true values
  2. Only one-half of the object is shown
  3. The drawing is twice the size of the actual part
  4. The drawing is half the size of the object Correct answer.

Explanation

Scale compares the size of the drawing to the actual object. Half scale means the drawn view is one-half the true size. The dimensions written on the drawing always state the true size regardless of scale.

Question 25Aircraft Drawings

What is the primary purpose of a schematic diagram?

  1. To list the part numbers needed for assembly
  2. To show the physical location of each wire in the aircraft
  3. To show how a system functions using standard symbols Correct answer.
  4. To give the exact dimensions of each component

Explanation

A schematic diagram uses standard symbols to show the functional relationship and flow through a system. It does not represent the physical location of components or wires. Physical routing is shown on a wiring diagram.

Question 26Aircraft Drawings

Fuselage station numbers are measured along which axis, and from what reference?

  1. Longitudinally from a datum point Correct answer.
  2. Vertically from the ground line
  3. Diagonally outward from the wing root
  4. Laterally from the centerline

Explanation

Fuselage stations measure distance fore and aft along the longitudinal axis of the aircraft. The zero point is an established datum, usually near the nose or firewall. Stations increase in the direction specified by the manufacturer.

Question 27Aircraft Drawings

Waterline numbers on an aircraft drawing indicate distance measured in which direction?

  1. Forward and aft from the nose datum point
  2. Left and right from the centerline
  3. Vertically from a horizontal datum Correct answer.
  4. Along the wing span from the root

Explanation

Waterlines are horizontal reference planes stacked vertically. A waterline number gives the height of a point above or below the horizontal datum. They are used together with stations and buttock lines to locate any point on the aircraft.

Question 28Aircraft Drawings

Buttock lines are used to locate a point at a given distance in which direction from the aircraft centerline?

  1. Laterally, left or right Correct answer.
  2. Longitudinally, fore or aft
  3. Vertically, up or down
  4. Radially, from the wing tip

Explanation

Buttock lines are vertical planes parallel to the centerline of the aircraft. A buttock line number gives the horizontal distance left or right of the centerline. The centerline itself is buttock line zero.

Question 29Aircraft Drawings

Compared with a detail drawing, an assembly drawing is intended mainly to show...

  1. how the individual parts fit together Correct answer.
  2. the allowable wear limits for a component
  3. every dimension needed to machine a single part
  4. the electrical continuity of a circuit

Explanation

A detail drawing fully dimensions one part so it can be manufactured. An assembly drawing instead shows the relationship and arrangement of several parts making up a unit. It may include a bill of materials and reference dimensions rather than full manufacturing dimensions.

Question 30Aircraft Drawings

What information does the bill of materials on an assembly drawing provide?

  1. The flight-hour limits for each component
  2. The part numbers and quantities of items used Correct answer.
  3. The repair procedures approved for the whole unit
  4. The torque sequence for each fastener

Explanation

The bill of materials, or parts list, tabulates each item in the assembly by part number, description, and quantity. It may also give the manufacturer's code and the drawing zone where the item appears. It does not contain maintenance or operating limits.

Question 31Aircraft Drawings

Which statement describes an isometric drawing?

  1. It uses a grid of zones to locate components
  2. It shows only one face of the object, true size
  3. It shows three dimensions in one pictorial view Correct answer.
  4. It shows internal parts by cutting away a section

Explanation

An isometric drawing is a pictorial view in which the three principal axes are drawn equally inclined, so length, width, and height appear in one view. It gives a realistic three-dimensional impression without a multi-view layout. Isometric views are generally not dimensioned for manufacture.

Question 32Aircraft Drawings

A five-digit Federal Supply Code for Manufacturers (FSCM) on a drawing is used to...

  1. identify the company that manufactured the part Correct answer.
  2. specify the material specification of the part
  3. show the aircraft station where the part is installed
  4. record the date the drawing was last revised

Explanation

The FSCM is a coded number assigned to a manufacturer for identification. When it appears with a part number, it identifies the specific company that makes or controls the part. This helps ensure the correct replacement part is obtained.

Question 33Aircraft Drawings

What is the purpose of the revision block on an aircraft drawing?

  1. To describe the finish to be applied
  2. To record changes made after release Correct answer.
  3. To show the weight of each subassembly
  4. To list the tools required to build the part

Explanation

The revision block tracks each change made to a drawing after its initial release. It usually shows a revision letter or number, the date, and a brief description of the change. This lets maintenance personnel confirm they are working to the current configuration.

Question 34Aircraft Drawings

In third-angle orthographic projection used on U.S. aircraft drawings, where is the top view placed relative to the front view?

  1. To the left of the front view
  2. Directly above the front view Correct answer.
  3. Directly below the front view shown
  4. On a separate sheet

Explanation

Third-angle projection places each view on the side from which it is viewed. The top view therefore appears above the front view, and the right side view appears to the right. All necessary views are arranged together on the same drawing sheet.

Question 35Aircraft Drawings

A cutting plane line on a drawing indicates that...

  1. the surface must be finished to a smooth texture
  2. the object has been sliced to form a section view Correct answer.
  3. the dimension applies to the center of the hole
  4. the part is to be bent along that line

Explanation

A cutting plane line marks where an imaginary cut is taken through the object. The resulting section view shows the internal features exposed by that cut. Arrows on the line indicate the direction of sight for the section view.

Question 36Aircraft Drawings

A dimension is given as 2.500 plus or minus 0.005. What does this indicate?

  1. The part may vary by 0.005 per inch of length
  2. The dimension is nominal and is not to be measured
  3. The acceptable size ranges from 2.495 to 2.505 Correct answer.
  4. The size must be exactly 2.500 at inspection

Explanation

A plus-or-minus tolerance states the allowable variation from the nominal dimension. Adding and subtracting 0.005 from 2.500 gives the upper and lower limits of 2.505 and 2.495. Any size within that range is acceptable.

Question 37Aircraft Drawings

An installation drawing is best described as one that shows...

  1. the internal structure of a single machined part
  2. the electrical path through a circuit, shown in symbolic form
  3. the detailed dimensions required to fabricate a fitting
  4. the location of an item relative to its surrounding structure Correct answer.

Explanation

Installation drawings show where an item is placed and how it relates to the surrounding structure. They typically give attachment points, clearances, and reference dimensions rather than full manufacturing detail. They are used to install or replace equipment correctly.

Question 38Aircraft Drawings

What is the purpose of break lines on an aircraft drawing?

  1. To shorten a long part to fit the sheet Correct answer.
  2. To mark the outer limits of a tolerance zone
  3. To show the center of a symmetrical part
  4. To identify hidden internal edges

Explanation

Break lines indicate that a portion of a long or repetitive object has been omitted so the view fits the drawing sheet. The true length is still given by dimension. They are not used to conceal hidden features or to set limits.

Question 39Weight and Balance

In aircraft weight and balance work, the datum is

  1. an imaginary vertical plane from which all arms are measured Correct answer.
  2. the forward limit of the allowable center of gravity range
  3. a horizontal reference line passing through the main wheels
  4. the point at which the aircraft's total weight acts

Explanation

The datum is a reference plane chosen by the manufacturer and located at any convenient point ahead of, behind, or within the aircraft, from which every horizontal distance (arm) is measured. It is fixed for a given model and is neither a limit nor a balance point.

Question 40Weight and Balance

In a weight and balance computation, an item's arm is its

  1. vertical distance from the ground to the item's CG
  2. total distance the item may be moved without exceeding limits
  3. horizontal distance from the datum to the item's CG Correct answer.
  4. difference between the item's weight and the empty weight

Explanation

Arm is the horizontal distance measured parallel to the longitudinal axis from the datum to the item's own center of gravity, normally expressed in inches. Arms aft of the datum are positive, and arms forward of the datum are negative.

Question 41Weight and Balance

An item weighing 45 pounds is located at an arm of 30 inches. What is its moment?

  1. 75 pound-inches
  2. 1,350 pound-inches Correct answer.
  3. 675 pound-inches
  4. 13,500 pound-inches

Explanation

Moment is the product of weight and arm, so 45 pounds multiplied by 30 inches equals 1,350 pound-inches. Moments are positive for items aft of the datum and negative for items forward of it.

Question 42Weight and Balance

An aircraft has a basic empty weight of 1,100 pounds at an arm of 32 inches. A 190-pound pilot sits at an arm of 20 inches, and 300 pounds of fuel is loaded at an arm of 40 inches. What is the loaded center of gravity?

  1. 30.5 inches
  2. 34.2 inches
  3. 32.1 inches Correct answer.
  4. 33.0 inches

Explanation

Multiply each weight by its arm and total the moments (35,200 + 3,800 + 12,000 = 51,000 pound-inches), then divide by the total weight of 1,590 pounds. The result is approximately 32.1 inches aft of the datum.

Question 43Weight and Balance

For weight and balance purposes, aviation gasoline is normally assumed to weigh

  1. 7.5 pounds per gallon
  2. 8.35 pounds per gallon
  3. 5 pounds per gallon
  4. 6 pounds per gallon Correct answer.

Explanation

Gasoline is computed at 6 pounds per gallon, which converts usable fuel volume into the weight used in loading calculations. For comparison, oil is figured at 7.5 pounds per gallon and water at 8.35 pounds per gallon.

Question 44Weight and Balance

Before an aircraft is weighed to establish its empty weight and empty weight center of gravity, it must be

  1. weighed with the fuel tanks full and the oil at operating level
  2. weighed in a three-point attitude with the tail lowered
  3. leveled in the attitude specified by the manufacturer Correct answer.
  4. weighed with all removable equipment removed from the aircraft

Explanation

The manufacturer specifies how the aircraft is to be leveled, using plumb bobs, leveling lugs, or a spirit level, so that the horizontal arms measured from the datum are correct. Weighing in any other attitude introduces error into the arms and therefore into the computed CG.

Question 45Weight and Balance

An aircraft weighs 2,000 pounds and its center of gravity must be moved 2 inches aft. How much weight must be shifted from an arm of 20 inches to an arm of 60 inches?

  1. 200 pounds
  2. 100 pounds Correct answer.
  3. 50 pounds
  4. 40 pounds

Explanation

Weight to be shifted equals the total weight multiplied by the desired CG change, divided by the distance the weight is moved. Here (2,000 × 2) ÷ 40 = 100 pounds.

Question 46Weight and Balance

An aircraft has an empty weight of 1,200 pounds with an empty weight center of gravity at 40.0 inches. A 60-pound radio is removed from an arm of 30 inches and a 40-pound unit is installed at an arm of 90 inches. What is the new empty weight center of gravity?

  1. 40.0 inches
  2. 42.2 inches Correct answer.
  3. 43.6 inches
  4. 41.5 inches

Explanation

Subtract the removed item's moment and add the installed item's moment to the original moment: 48,000 minus 1,800 plus 3,600 equals 49,800 pound-inches. Dividing by the new weight of 1,180 pounds gives approximately 42.2 inches.

Question 47Weight and Balance

When an aircraft is weighed, the chocks and blocks that rest on the scales but are not part of the aircraft must be

  1. subtracted from the scale readings as tare weight Correct answer.
  2. ignored because they do not affect the center of gravity
  3. recorded as part of the aircraft's empty weight
  4. added to the scale readings as tare weight

Explanation

Tare is the weight of everything on the scales other than the aircraft itself, and it must be subtracted from each scale reading to obtain the true wheel weights. Failure to remove tare inflates the empty weight and distorts the computed center of gravity.

Question 48Weight and Balance

An aircraft loaded with its center of gravity near the forward limit will normally

  1. be more prone to spinning and harder to recover from a stall
  2. have a lower stall speed and a greater useful load
  3. cruise faster because of reduced trim drag
  4. need more back pressure to flare and stall at a higher speed Correct answer.

Explanation

A forward CG increases the nose-down moment that the tail must oppose, so the wing carries a greater load, raising the stall speed and requiring more elevator force to flare. Longitudinal stability is greater at a forward CG, and takeoff and landing distances increase.

Question 49Weight and Balance

Loading an aircraft so that its center of gravity is at or beyond the aft limit will

  1. have no effect on handling if the weight limit is respected
  2. increase the load carried by the nosewheel on the ground
  3. reduce the static margin and degrade pitch stability Correct answer.
  4. increase longitudinal stability and require more back pressure in the flare

Explanation

As the CG moves aft, the distance between the center of gravity and the aerodynamic center, known as the static margin, shrinks, so the aircraft resists pitch disturbances less and becomes easier to stall and spin. Aft loading also unloads the nosewheel and can make the aircraft uncontrollable.

Question 50Weight and Balance

The leading edge of the mean aerodynamic chord is at an arm of 60 inches and the MAC is 60 inches long. If the loaded center of gravity is at an arm of 75 inches, the CG location is

  1. 20 percent MAC
  2. 15 percent MAC
  3. 40 percent MAC
  4. 25 percent MAC Correct answer.

Explanation

Percent MAC is the distance from the leading edge of the mean aerodynamic chord to the CG, divided by the chord length and multiplied by 100. Here (75 − 60) ÷ 60 × 100 = 25 percent.