Practicing flying the MDA with the AP on an RNAV (GPS) approach.

Ride along as I fly a 2D, non-precision RNAV approach to practice one technique for leveling off while using AP on to maintain the lateral track and hold the MDA until reaching the missed approach point. I flew from Boeing Field in Seattle to William Fairchild International Airport (KCLM) at Port Angeles, WA, on the north side of the Olympic Peninsula. It’s a scenic flight that takes you close to NAS Whidbey Island and the Coast Guard Air Station Port Angeles. I started the RNAV (GPS) RWY 27 at JAWBN and then flew two intermediate legs to the FAF at FAMUV, descending as charted along the way. The procedure is a 2D, non-precision approach that provides LP minimums to an MDA of 760 ft. It requires 1 sm visibility. Note that the VDP is 1.5 nm from the MAP. Normally I treat a VDP as the decision point and go missed if the runway environment isn’t in sight. But on this approach, if you are prepared, continuing at the MDA in low visibility for about another half mile could reveal the runway, with time in a typical single-engine piston to descend about 500 ft to a landing on the 5000 ft remaining past the displaced threshold. That’s where using the AP to maintain the MDA and the track toward the runway could help as you look for the runway. But you must understand and practice using the functions of your AP to avoid confusion during this critical phase of flight. On this practice approach, I used the control wheel steering (CWS) feature of the GFC 600 to smoothly level off at the MDA, and then I selected ALT hold to maintain that altitude to the MAP. Some APs, like the popular GFC 500, don’t have a CWS function. In that case, selecting ALT hold usually works. But you should practice using the avionics in your airplane on a nice VFR day, as I did in this video, to ensure you understand the best technique to use while flying a 2D approach if you decide to continue past a VDP or the intersection of an advisory GP and the MDA.