DME, ILS & GNSS (GPS) Flashcards
DME uses the ____ principle based on SSR.
DME uses the transponder principle based on SSR
DME operates in the ____ frequency band
UHF
DME readouts give (ground, earth, straight, slant, triangle) range between the aircraft and ground station
What is the correct answer?
give **slant **range between aircraft and ground station
DME channels are normally paired with a ____ or ____
paired with a **VOR **or ILS
When tuning in a DME paired with a VOR you would normally tune the (VOR, DME, NDB, ADF) frequency on the NAV-COM set
What is the correct answer?
normally tune the **VOR **frequency on the NAV-COM set
When a DME is tuned with a paired VOR, two IDENT signals with (the same code, a different code) will be heard. The DME IDENT will be of a (higher, lower) pitch than the VOR IDENT
Which combination gives the correct answer?
When a DME is tuned with a paired VOR, two IDENT signals with **the same code will be heard. The DME IDENT will be of a **higher pitch than the VOR IDENT
If a DME signal is lost, this will be indicated on the display by…
the DME scrolling rapidly from 0nm to 200nm and at the same time the OFF flag or bar/line across the read out will appear
The ground DME transponder can typically provide responses to a max of ____ aircraft at the same time
**100 **aircraft
Describe DME saturation
**When the ground DME transponder is trying to provide responses to more than 100 aircraft at the same time it will become saturated and only the strongest signals will be replied to, weaker signals will be ‘unlocked’ **
If TACAN is paired with a VOR it is called _____
VORTAC
Civilian aircraft can obtain (distance and bearing, distance only, no information) from TACAN
What is the correct answer?
Civilian aircraft can obtain distance only from TACAN
DME is designed to have a max range of ____nm at 30,000ft and is line of sight.
200nm
Use the correct formula to calculate expected DME signal range for an aircraft at 32,000ft with a ground DME station elevation of 800ft
**254.81nm
(square root of DME elevation x 1.23 + square root of aircraft height x 1.23)**
State the calculation to find DME/Slant range given Plan/ground range
**First convert aircraft height to nautical miles
(divide by 6076)
Slant range = square root of (plan/ground range²) + (aircraft height in nm²)**
With relation to DME, What is horizontal/plan range and how is it calculated?
**Is the distance over the ground to the DME station
It can be calculated by first converting aircraft height to nautical miles (divide height by 6076)
Plan Range = square root of (slant range²) - (aircraft height in nm²)**
The ILS Localiser signal uses the ____ band
VHF
ILS Localiser frequencies have an **(odd, even) **number after the decimal point
What is the correct answer?
have an odd number after the decimal point
e.g. 110.3, 110.9 etc
ILS Localiser transmitts two beams that overlap. The left beam is at ____Hz and is refered to as the ____ colour, while the right beam is at ____Hz and refered to as the ____ colour
ILS Localiser transmitts two beams that overlap. The left beam is at 90Hz and is refered to as the **Yellow **colour, while the right beam is at 150Hz and refered to as the Blue colour
ILS Localiser coverage is generally limited to?
25nm and to within (+-) 10°of localiser centreline.
A signal can also be received when 17nm out and within (+-) 35° of the centreline
The CDI needle shows displacement from the LOC Centreline, it (does, does not) provide heading information
does not
With regard to ILS Localiser, Each dot on the CDI instrument represents ____°
0.5°
For every nautical mile away from the ILS LOC transmitter, each dot on the CDI instrument (0.5°) represents ____ft left or right of the LOC centreline
50ft
ILS Glideslope uses the ____ band
UHF
Like the ILS Localilser, the Glideslope signal also uses two lobes of 90Hz and 150Hz and are arranged inclined ____° from the (horizontal, vertical)
What is the correct answer?
inclined 3° from the Horizontal