Radars and navigational aids Flashcards
What is Primary Surveillance Radar (PSR)?
It provides only very basic information about the position of an aircraft in relation to the radar.
It will show all aircraft within its coverage and will also show other objects like high terrain, certain weather and possibly large flocks of birds
What is Secondary Surveillance Radar (SSR)?
SSR is selective, and only displays information from aircraft equipped with a transponder.
Aircraft is allocated an individual four-digit code, which the pilot dials up in the transponder. The ground based radar interrogates the transponder and when it recognises the code, which is allocated to that particular flight, the aircraft’s height information and callsign is displayed to the Controller.
The Controller is also able to display maps of airways and upper air routes as well as coastlines and danger areas.
What is VOR?
VOR is the VHF Omni-directional Range, the most accurate of the gound based nav aids, which emits radial signals which aircraft can fly along. The range of VOR is in the order of 125 NM.
There are 360 radials which a/c could fly towards and away from a VOR. Each radial represents 1 degree from 0-359 degrees.
What is DME?
DME stands for Distance Measuring Equipment. VORs often have an associated DME with them. This show the pilot how far the aircraft is away from the VOR?
What is NDB?
NDB stands for a Non-Directional Beacon, and it emits a signal which the pilot navigates toward. The range of most NDB is in the region of about 25 NM
How does Space Based Navigation work?
Aircraft will gather data from various sources, e.g. Navigational Aids, Inertial Navigation Systems, GPS, and the information is then fed into the Flight Management System (FMS)
What is ILS?
ILS stands for Instrument Landing System. The ILS is a ground-based radio guidance system which transmits two directional radio beams, the localiser (left/.right) and the glide path (up/down).
The usual descent path for ILS is 3 degrees.
