Aircraft Electrical Systems

Question 1

What controls the output voltage of an alternator?

Answer 1

The generator control unit – GCU

Question 2

How long should bonding jumper wires be?

Answer 2

A short as practical, but long enough to allow free movement of the component

Question 3

What factors are considered when selecting wire size for electrical power?

Answer 3

Permissible voltage drop, the system voltage, wire length, current carrying and if the load is continuous or intermittent

Question 4

How can a particular wire in a bundle be identified?

Answer 4

By the identification code on the wire

Question 5

What would you use to determine the size of an unmarked wire?

Answer 5

A wire gauge

Question 6

What size electrical conduit should be used?

Answer 6

25% larger than the maximum diameter of the wire bundle

Question 7

What should be done to a conduit when fittings are not used?

Answer 7

It should be deburred to prevent insulation damage

Question 8

What hardware is used to make bonding or grounding connections to a structure of the dissimilar metal?

Answer 8

A washer of suitable material should be use for the corrosion will occur on the washer

Question 9

How many terminal lugs can be put on a single terminal strip start in an aircraft?

Answer 9

4

Question 10

When do DC motors draw several times their current rate?

Answer 10

When starting

Question 11

Why is a circuit breaker designed to be open?

Answer 11

When an overload or circuit fault exists and before the wire emits smoke

Question 12

What type of circuit breaker should not be used in aircraft?

Answer 12

Automatic reset type circuit breakers

Question 13

What color is left and right wing tip position light?

Answer 13

Left side is red and right side is green

Question 14

Where is the white position/navigation light mounted?

Answer 14

On the tail visible from the rear

Question 15

What could cause an AC electric motor to run too fast?

Answer 15

Excessive applied voltage on shorted fielded windings

Question 16

What tool is used to check a motor or generator armature for shorts and opens under load conditions?

Answer 16

A growler

Question 17

When, using a growler, what indication will occur when a short exist between an armature segment?

Answer 17

With a metal blade is held over the armature and short exists in a segment, the blade will begin to vibrate and chatter

Question 18

How is the output voltage of an alternator controlled?

Answer 18

By varying the current field that exits the alternator

Question 19

What instruments are used to monitor electrical system loads?

Answer 19

Ammeter and voltmeters

Question 20

Why would it be necessary to analyze electrical system before increasing the load on the system?

Answer 20

To determine the generator capacity, wire size and to not exceed the protective device capacity

Question 21

Name several types of electrical devices that would be considered intermittent loads on the electrical system

Answer 21

Landing gear, Cowl and wing flap motors, radio, transmitters

Question 22

Under what conditions must a switch be derated from its nominal rating?

Answer 22

When used with inductive circuits, circuits with a high in-rush current, and with DC motors

Question 23

At what point in a circuit should the protective device be located?

Answer 23

As close to the source as possible

Question 24

What can cause an AC electric motor to run too slowly?

Answer 24

Lack of lubrication, defective wiring or low-voltage

Question 25

Prior to making a continuity check what must be done to the electrical circuit?

Answer 25

The power must be turned off