I have been in electronics from 1950 to 1989 when I retired. Therefore I chose as my theme "Instrument Landing Systems" or ILS. This system helps aircraft land and is used at all times, but mostly under reduced visibility conditions. My position at Transport Canada was "Navaid Specialist". I supervised the installation and commissioning of Navaids throughout the Quebec region. Safety and Security could never be compromised.
In nearly 60 years of use ILS systems were never found at fault in an airplane Crash. This flawless record is a direct result of the training given to Navaid technicians. While training, technicians are told that the equipment cannot be allowed to operate outside the established tolerances. Any doubt and the equipment is shut down pending reevaluation and recertification.
- Brief Description (See below.)
- Picture of ILS
- Description of Localizer
Brief description for those rushing (to other sites).
The ILS usually consists of a Localizer, Glide Path, and Markers(OM, MM, & IM).
Localizer: This equipment provides lateral guidance to the runway centerline from
about 5nm out.(five nautical miles).
Glide Path: This equipment provides the aircraft with a glide angle - usually 3 degrees.
The Localizer and Glide Path combine to bring the aircraft to a point where the aircraft
is 50 feet high at the runway threshold (decision point).
Markers:
1. The Outer Marker at approximately 5nm helps the a/c adjust its course and height.
2. The Middle Marker is located at approximately 3500 feet and used similarly.
3. The Inner Maker at 1000 feet is used only for Category II operations.
Exceptions:
There are always exceptions and here are some main exceptions.
1. DME & GP (Distance Measuring Equipment & Glide Path) when it is impossible to
have Markers.
2. DME & Localizer when there is no GP for whatever reason.
3. Offset Localizer. In this case the Localizer is not on the runway centreline,
but offset and lined up to bring the aircraft over the threshold at decision height.
Decision height is 50 feet at threshold.