Monday, March 4, 2013

Video: Porto ILS rwy17 approach

This post is about one of my first ILS approaches that I have done on Porto airport. It was a great flight, passing through clouds and flying low along the shoreline.

Non-pilots may be asking what the heck is an ILS approach? 
I'll try to explain the basics behind this system.
ILS stands for Instrument Landing System and helps the pilots bring the airplane to near the runway or in some cases to do an automatic landing in poor visibility.

This system is divided in 2 parts:
- Localizer: This gives horizontal guidance, telling the pilot if is left or right of the runway centerline.

Localizer antennas
 - Glide slope: This gives vertical guidance, telling the pilot if he is below or above the glide path. This glide path normally has a slope of about 3 deg. The glide path antenna is located at the point of touchdown.
Glide path antenna
The instrument that I use in the airplane to guide me to the runway is like this one:
CDI - Course Deviation Indicator
The goal is to maintain the lines perpendicular (try to see this in the video). The easy way to fly this is "turn to the needle". Here are some examples:
Localizer guidance
Glideslope guidance

For practice, normally, I do this approaches under the hood (can not see the outside) and I can only look out when I'm at the "minimums" (point where I have to abort the landing if I can not see the runway). This point is about 200 feet/60m of height. 

Here is the video that I did: