Instruments And Navigation Aids

Question 1

What is TAWS?

Answer 1

Terrain Awareness and Warning System

Question 2

FMS stands for…

Answer 2

Flight Management System

Question 3

ADF stands for…

Answer 3

Automatic Direction Finding.

Question 4

INS stands for…

Answer 4

Inertial Navigation System

Question 5

What are multi-channel receivers able to do?

Answer 5

Assign and lock onto individual satellites per channel enabling them to track and compute the most accurate position using the best satellites. Reduces the ‘Geometry dilution of precision’ effect. That is the fact that the system is more accurate using larger angles relative to the aircraft.

Question 6

RMI stands for…

Answer 6

Radio magnetic indicator

Question 7

What is ADS?

Answer 7

Automatic Dependant Surveillance

The ability for ATC to track aircraft using GPS position and use data for communication.

Question 8

Explain FANS

Answer 8

Future Air Navigation System
Implementation of satellite technology for improved communication, navigation, air traffic management and surveillance.

Not a single specific system but the ongoing development of several navigation based systems.

Question 9

ILS stands for…

Answer 9

Instrument Landing System

Question 10

HSI stands for…

Answer 10

Horizontal Situation Indicator

Question 11

VOR stands for…

Answer 11

VHF omnidirectional range

Each dot represents 5 radials

Question 12

How many degrees per dot for an ILS?

Answer 12

1 dot = 1/2 degree for localiser.

1 dot = 0.15 degree for glideslope.

Question 13

How does TCAS interrogate aircraft?

Answer 13

It uses transponder signals from other aircraft to determine relative positions.

Question 14

ADI stands for…

Answer 14

Attitude Direction Indicator

Question 15

What are the altimeter errors?

Answer 15

1. Instrument error,
2. Pressure error,
3. Time-lag error,
4. Barometric error,
5. Temperature/density error,
6. Blocked static port.

Question 16

List the TCAS symbols

Answer 16

Surveillance Traffic - Unshaded white diamond
Proximate Traffic - Sold white diamond - Traffic within 6nm and 1200’
Traffic Advisory - Solid amber circle - Will enter TCAS collision airspace within 35-40s.
Resolution Advisory - Solid red square - Will enter TCAS collision airspace within 20-30s.

Question 17

Describe how a Mach meter works

Answer 17

Combines an ASI and Altimeter.

Mach number = dynamic pressure/static pressure - mathematically proven.

Doesn’t suffer from density or temperature errors because its in-built capsule design and its ratio to the dynamic pressure measured, compensate for density and temperature variations.

Question 18

How does EGPWS (TAWS) Operate?

Answer 18

It has a worldwide terrain database which it references against GPS position and altitude information, and RADALT. It is forward looking.

Question 19

DME stands for…

Answer 19

Distance measuring equipment

Question 20

What errors does a VSI suffer from?

Answer 20

1. Instrument time-lag error,
2. Pressure error,
3. Manoeuvre error.

Question 21

What is Differential GPS?

Answer 21

It uses ground based receivers at a known location to calculate error in the satellite data. This is then sent to airborne units to further refine their position information.

Question 22

What happens to an ASI with a blocked pitot or static ports?

Answer 22

Blocked static:
Level flight - correct reading.
Descent - over-read.
Climb - under-read.

Blocked pitot:
Level flight - static reading.
Descent - under-read.
Climb - over-read.

Question 23

What errors does an ASI suffer from?

Answer 23

1. Instrument error,
2. Pressure error,
3. Compressibility error.
4. Density error,
5. Manoeuvre error,
6. Blockages.