Why are some approaches, like RNAV Z 22L at midway, not on centerline?

i flew into midway this morning and the RNAV Z 22L has an approach course of 238, while the runway heading is 220. I had to make a last minute centering of my aircraft to land on center line. Why is the approach set up like this? how is this safe? wouldn’t you want approaches to be established so that little adjustment is needed before landing?

image

1 Like

If you look closely, you will see 700 foot buildings on short final as well as 1100 foot buildings further on the straight in, so I assume it is to avoid those. If you look at DCA, it has a sharp final turn on the river visual, and that is to avoid downtown Arlington and Rosslyn while avoiding the restricted P-51 airspaces just to the north.

5 Likes

that is known as a SOIA aprroach (simultaneous offset instrument approach), used to allow for simultaneous parallel runway operations. its the same case at KSFO with the 28s

2 Likes

and that as well

1 Like

thanks for the responses… i can understand the avoidance of obstacles… don’t want to hit anything. there is a RNAV Y that does go straight in. So we just need to live a quick turn on final?

1 Like

Yes, the GPS approach is a non precision approach and in this case its offset to give some spacing as Robert said. Notice the RNP RNAV approaches, this is “required navigation performance” and requires a higher accuracy of the GPS, which most commercial aircraft have, so you can do those as well

1 Like

It’s perfectly safe and fine! Adding on what has been said before this procedure ends at a waypoint shortly before the runway, which leaves enough time to make a visual turn onto the runway heading. Many airports have offset approaches, often for terrain avoidance. Sometimes you can also deviate from the final course once you are clear of all obstacles and visual, but that depends on the set airport and it’s procedures.

Not a risk to safety at all as you would have to go-around if you are not visual once reaching the final fix!

1 Like