ok I just realized that the smaller yellow circle in the 2nd picture is the auto pilot heading indicator, still don't know what that rectangle is though.
Finally getting ILS landings with Jets down, it makes landings so much smoother with the proper rear wheels going down first, will post a vid soon
Hi Mark, the rectangle you refer to is the heading indicator of the VOR indicator. It moves towards the centerer as you come nearer to it's alignment.
Using a radio frequency that is set with that particular VOR or ILS you can move the heading indicator to correspond to the runway heading or VOR heading. A VOR is a signal allowing you to navigate to a certain place whilst an ILS is specific to a runway.
Imagine runway 09 has a heading of 87 degrees and a frequency of 108.45. You programme that frequency into the nav radio for VOR 1 and set up the runway heading and you will be able to align the plane using the rectangle as well. But you can also say I need to get to point B that has a radio frequency of 109.75. Using the VOR i can programme the correct heading so that i intersect a line that will take me to that particular VOR.
It only gives heading of course and not height. It is an additional visual indicator for the pilot to help him get and stay on course. The ILS indicator (above) is more fine tuned to landing and the VOR (below) more to getting enroute.
Hope it makes sense somewhere!
The O M I indicators are additional aids for the pilot. As he approaches the runway there are three marker points telling him where he is on the approach: outer, middle and inner. These indicators light up as he approaches these markers giving him additional information about his position and whether he is on the correct pathway. We have to realsie that a plane never ever lands, in usual circumstances, without a detailed chart of the airport, its runways and how to land them within safety and noise restrictions. Airports are very, very tightly controlled entities and a pilot must ahve the appropriate charts with him telling him how to approach the runway, how high he should be and when, and how fast he shoudl be going at which height and distance. These charts aid him as well as the various indicators to guide his aircraft safely to a landing even when he cannot see the runway!