NAV - ILS Flashcards
1
Q
What is an ILS? (5)
A
ILS - Instrument Landing System
- Precision approach (azimuth and elevation)
- Runways are known as Precision Approach Instrument Runways
- For poor weather (cloud / visibility)
- Assists in achieving an orderly flow of landing traffic
2
Q
What is the Localiser Transmitter? (3)
A
- Situated beyond the upwind end of the runway approx. 300m from the threshold
- Defines the extended centreline of the
instrument runway - Indicates deviation from the optimum lateral approach path
3
Q
What is the Glidepath Transmitter? (3)
A
- Situated approx. 300m from the landing threshold and offset between 100 & 200m from the centreline
- Defines the safe descent slope (normally 3°)
- Indicates deviation from the optimum verticalapproach path
4
Q
What are the 3 Marker beacons? (3)
A
- Outer marker
- Middle marker
- Inner Marker
5
Q
What are the characteristics of the Outer Marker? (3)
A
- 3-6nm from threshold
- Tx 2 dashes per sec at 400Hz
- Flashes blue light in cockpit
6
Q
What are the characteristics of the Middle Marker? (3)
A
- 900-1200m from threshold
- Tx alternate dot dash at 1300Hz
- Flashes amber light in cockpit
7
Q
What are the characteristics of the Inner Marker? (3)
A
- 300 – 450m from threshold
- TX 6 Dots per sec at 3000hz
- Flashes white light in cockpit
8
Q
ILS & Marker beacons diagram
A
9
Q
How is a DME used for an ILS? (3)
A
- Paired with ILS - Both auto tuned when selected
- Range info is “0” to the Runway threshold
- Accurate only within localizer coverage and up to 25,000ft
10
Q
ILS Transmitters WITH DME diagram
A
11
Q
What are the characteristics of the Localiser? (5)
A
- VHF Band: 108-112 Mhz
- Radiates 2 lobes - overlap by 5°
- Modulates 90 & 150 Hz in either centreline side
- Unequal signals indicates left / right of centreline
12
Q
What is the Localiser protected range? (3)
A
- Coverage 35° either side of centreline
- 17 nm
- Reduces to 10° thereafter up to 25nm
13
Q
Which ICAO annex indicates ILS facilities to conform to? (1)
A
Annex 10
14
Q
What are the characteristics of the Glidepath? (4)
A
- UHF band: 329.3 - 335 Mhz
- Radiates 2 lobes - overlap by 1° - Range of 10nm
- Known as ILS Reference Point
- 3° descent angle
- Deviation either above or below results in unequal signals being received
15
Q
What is the Glidepath protected range? (2)
A
- Coverage 8° Azimuth side of localiser centreline
- 10 nm from threshold