13. Navigational Aids

Question 1

What is the purpose of navigational aids? (Which NATS provides and maintains)

Answer 1

To enable ACFT to fly the airways system with the necessary accuracy.

Question 2

What does VOR stand for?

Answer 2

VHF (Very High Frequency) Omnidirectional Range.

Question 3

How does a VOR work?

Answer 3

By emitting radial signals which the ACFT can fly along. There are 360 radials an ACFT can use to fly to or from the VOR, each representing 1 degree.

Question 4

What is a DME?

Answer 4

Distance Measuring Equipment - often associated with a VOR and shows pilots how far away they are from the VOR

Question 5

Due to their accuracy, VORs can be used to establish _____. Heathrow has 4 inner holds that are __________ overhead VORs. The range of a VOR is in the order of _____ nautical miles.

Answer 5

1. ) holds.
2. ) Established
3. ) 125.

Question 6

What is an NDB and what is their range?

Answer 6

1. ) Non-Directional Beacon - Emits a signal which the pilot navigates towards.
2. ) Much shorter range than a VOR at around 25 nautical miles.

Question 7

Why are an increasing number of approach and en-route navigational aids being phased out?

Answer 7

GPS is becoming more accurate, capable, reliable and widespread.

Question 8

ACFT gather data from various sources e.g. _____, _____, _____ and the information is fed into the _______________ (FMS).

Answer 8

1. ) Navigational Aids.
2. ) Inertial Navigation System (INS).
3. ) GPS.
4. ) Flight Management System.

Question 9

The FMS can vary in complexity from basic _____ and _____ to the systems which can control the ACFT from _____ to _____.

Answer 9

1. ) Heading.
2. ) Altitude hold.
3. ) Departure.
4. ) Arrival.

Question 10

Approach controllers issue instructions to enable the ACFT to intercept the ILS. What is ILS? (4)

Answer 10

1. ) Instrument Landing System.
2. ) Ground-based radio guidance which transmits 2 directional radio beams - the localiser and the glide path
3. ) Pilot receives indications in the cockpit advising if the ACFT needs to fly up, down, left or right to keep on the correct approach path.
   4) the usual decent path for ILS is 3 degrees