ILS Flashcards
(40 cards)
ILS
Instrument Landing System
An ILS provides precise ____________ and ___________ guidance
- Azimuth
- Glide slope
The minima of an ILS will be:
a Decision Height (DH) or Decision Altitude (DA)
Visibility and Height minima for ILS Cat 1?
Vis: 800m
Height: Not below 200ft
Visibility and Height minima for ILS Cat 2?
Vis: 350m RVR
Height: Not below 100ft
Visibility and Height minima for ILS Cat 3A?
Vis: 200m RVR
Height: Below 100ft or 0
Visibility and Height minima for ILS Cat 3B?
Vis: 50m RVR
Height: Below 50ft or 0
Visibility and Height minima for ILS Cat 3C?
Vis: 0
Height: 0
What are the components of an ILS?
- Localiser transmitter & aerials
- Glide slope transmitter and aerials
- DME
- High Intensity Approach Lighting (HIAL)
The localiser provides ___________ guidance
azimuth
The glide path provides __________ guidance
vertical
Where is the localiser aerial located?
Upwind on the extended centreline
The localiser carries the _________ ident
morse
A localiser sends out two overlapping signals. What are they?
- 150Hz tone right of the runway (blue zone)
- 90Hz tone left of the runway (yellow zone)
Where is the glide path aerial positioned?
Adjacent to the aiming point.
What is the frequency range of the glide path?
329 MHz to 335 MHz
What is the frequency range of the localiser?
108MHz to 112 MHz
Based on 3° Glide Path an aircraft will lose ____________ per NM travelled.
approx 300ft (more like 318) per NM travelled.
Of the two signals sent by a glide path, which is the higher (vertically)?
90Hz
Of the two signals sent by a glide path, which is the lower (vertically)?
150Hz
DME may be associated with an ILS to provide a pilot with what?
A cross-check of height/distance-to-run
Where is ILS DME typically located?
With the glide path.
Where no DME is associated with an ILS what can be used instead?
GNSS
What may be located prior to the ILS procedure Initial Approach Fix (IAF)?
An NDB.
