RNAV Approach at KCLS

I flew an RNAV (GPS) approach at Chehalis, WA (KCLS) to show how low LPV minimums can take you, even to a runway at a typical small-town, non-towered airport that doesn’t have approach lights and other components associated with precision approaches. I flew this procedure in VMC to help you see the runway environment.

Now, an RNAV (GPS) approach to LPV minimums isn’t technically a precision approach, at least according to the current ICAO definition of the term. But as a practical matter, flying to a localizer performance with vertical guidance DA is just like flying an ILS. The lateral guidance funnels you toward the runway, just like a localizer, and the glidepath generated by the GNSS box in the panel acts just like an ILS glideslope. In fact, I prefer flying an LPV approach even when an ILS is available. You don’t have to switch navigation sources, there are no false glideslopes, and there is no ILS critical area.

If the runway served by the RNAV (GPS) approach doesn’t also have an ILS, you probably won’t see approach and runway lights except for edge lighting. And the minimums (DA and visibility) will be a little higher than they would be for a typical category 1 ILS (i.e., 200-1/2). At KCLS, the LPV minimums are 300 AGL (DA 476) and 1 mile.

But those minimums are a substantial improvement over the LNAV MDA (900 MSL; 724 AGL), the lowest you can go without the approved vertical guidance available with WAAS.

2 thoughts on “RNAV Approach at KCLS”

  1. It must have been something to do with the camera view but it did not appear like a typical 3 degree glide path …. seemed flatter to me. Took me longer to pick out the runway than I thought it would. Finally figured out why you are always landing right of center line….camera location duuuhhhh. Flew just east over Swantown Marina in Olympia East Bay, I could almost see my sailboat at the slip! — Chris

    1. When the view cuts to the panel view, you can see that I am on the LPV glidepath. And the cockpit view, looking over the nose, shows alignment with the runway centerline. It is harder to pick out the runway when you don’t have approach lights, etc. That’s the main point of the video.

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