Aircraft Instrument Systems

Question 1

What flight instruments are usually normally connect to a pitot-static system?

Answer 1

Airspeed indicator, vertical speed indicator, and altimeter.

Question 2

What instrument indications will result if the static pressure line becomes disconnected inside the cabin of a pressurized aircraft?

Answer 2

The altimeter and airspeed indications will both be lower than normal, and the vertical speed will indicate a momentary decent then return to zero.

Question 3

Who is authorized to perform tests to calibrate an altimeter?

Answer 3

The manufacture, or a certified repair station.

Question 4

What is required after replacement of components connected to the pitot-static system?

Answer 4

A leak test.

Question 5

In wet-type vacuum pumps, what are the vanes made from?

Answer 5

Steel.

Question 6

How are vanes of a wet-type pump lubricated?

Answer 6

Engine oil.

Question 7

What are the sources of power to gyroscopic instrument operation?

Answer 7

Gyroscopic instruments can be operated either by vacuum, electricity, or air pressure.

Question 8

What causes an electric driven gyro rotor to tilt when the aircraft is turned?

Answer 8

Gyroscopic precession.

Question 9

What is used as a reference for range marking of aircraft instruments?

Answer 9

The Aircraft Specifications, or Type Certificate Data Sheets and the specific aircraft maintenance manual or flight manual.

Question 10

Where are instrument range markings placed?

Answer 10

They are applied to the outer edge of the cover glass or over the calibrations on the dial face of the instrument.

Question 11

What other type mark is required when range markings are applied to the glass instrument cover?

Answer 11

An index mark, which is a white line extending from the glass cover onto the instrument case to indicate slippage of the glass. Glass slippage would cause the range markings to be in error.

Question 12

What is a syncro-type remote indicating system?

Answer 12

These systems can be used to show movement and position of landing gear, wing flaps, oil cooler doors, or other movable parts of the aircraft. A synchro system is an electrical system used for transmitting information from one point to another. The three most common synchro systems are the Autosyn, the Selsyn, and the Magnesyn.

Question 13

What type of fuel quantity system is an electric fuel measuring device that accurately determines the density weight of the fuel in the tanks of an aircraft?

Answer 13

The capacitor fuel type quantity system.

Question 14

What is meant by “swinging a compass”?

Answer 14

Correcting for deviations by adjusting the compensating magnets.

Question 15

When inspecting a magnetic compass, the bowl should be filled with liquid and should not contain any bubbles or discolorations. What is the purpose of the liquid in the bowl?

Answer 15

To dampen the oscillations of the float.

Question 16

What is the fluid used in a magnetic compass?

Answer 16

A clear fluid such a kerosene.

Question 17

Where is the compass correction card placed?

Answer 17

Near the compass and in plain sight of the pilot.

Question 18

Which instrument is used to indicate the speed of the crankshaft of a reciprocating engine and the speed of the main rotor assembly in a turbine engine?

Answer 18

A tachometer.

Question 19

What type of indicating system is used to indicate turbine engine exhaust gas temperature?

Answer 19

A thermocouple system

Question 20

What does the manifold pressure gauge indicate when the engine is not operating?

Answer 20

It indicates atmospheric pressure.

Question 21

What is used to check a manifold pressure gauge for correct indication when the engine is not operating?

Answer 21

Either a barometer, or an altimeter after it has been set to zero.

Question 22

What is the meaning of the yellow range on the airspeed indicator?

Answer 22

The yellow arc designates the cautionary range.

Question 23

What does a Mach meter indicate?

Answer 23

The ratio of aircraft speed to the speed of sound at a specific altitude and temperature during any time in flight.

Question 24

Why do you not try to remove a blockage in a pitot system?

Answer 24

To prevent further damage to the pitot system

Question 25

What does a yellow arc on an instrument dial indicate?

Answer 25

Caution.

Question 26

When range markings are placed on an instrument glass, what precaution must be taken?

Answer 26

The glass must be marked for slippage indication.

Question 27

What indication errors may be found in altimeters?

Answer 27

Scale, hysteresis, and installation.

Question 28

What methods are used to drive turn-and-bank/slip indicators?

Answer 28

Vacuum, air pressure, or electricity.

Question 29

What does a tachometer indicate?

Answer 29

Crankshaft or main turbine rotor speed.

Question 30

Why are slippage marks used on instrument glass covers?

Answer 30

To indicate glass rotation in the bezel.

Question 31

What is synchro-type remote indicating system?

Answer 31

A system that transmits information from one point to another point.

Question 32

Where does an electrical resistance temperature indicator receive a signal?

Answer 32

From a temperature-sensitive element.

Question 33

Name at least two items that should be looked for during an inspection of a magnetic compass?

Answer 33

(1) security of attachment. (2) correct readings at various heading. (3) the bowl should be filled with liquid and not contain any bubbles or discoloration. (4) the scale should be readable. (5) moving parts should work easily.

Question 34

What can be used to static check a manifold pressure indicator?

Answer 34

Current atmospheric pressure.