Using VNAV on an Approach at KBVS

[@christophvz]

Nice job slowing down to maintain separation from the landing traffic. I’ve noticed that you maintained over 1nm separation at all times. Is 1nm your personal rule (where you’d break off the approach if you got any closer) or a coincident? If not, do you have a minimum or does it depend on factors such whether you’re converging ? 11:46

[@BruceAirFlying]

I am acutely aware of recent accidents, such as the mid-air at Watsonville (KWVI), where a twin continued a straight-in approach at high speed and collided with a Cessna which was in the pattern ahead. That's why I slowed down and made additional position reports and confirmed on the CTAF that I had the aircraft on base in sight. I didn't have a specific distance (e.g., 1 nm) in mind. I just kept the airplane ahead in sight and adjusted speed early to allow safe spacing as I got to short final. I also make position reports relative to the airport, not to fixes on an approach. Those fixes may not be familiar to non-IFR pilots and pilots who don't have the approach chart available.

[@wheelerdavea]

Thanks again for the ride along. When you reduce power on a coupled approach, does the trim automatically engage, or is glide path maintained solely by elevator pressure?

[@BruceAirFlying]

My GFC 600 (and many GFC 500 installations) autopilot has a trim servo, so it adjusts elevator trim as airspeed varies and when you change configuration, such as extending flaps and landing gear. My autopilot also has a yaw damper that handles that axis.

[@wheelerdavea]

@@BruceAirFlying That's awesome. The last "real" autopilot I flew was our old KFC200, that would fly a coupled ILS or GPS approach but you still had to manually keep the trim up to date.

[@tammaramma]

Hey Bruce, could you do a tutorial on a non-precision approach using the GFC autopilot. I haven't seen one of those yet.

[@BruceAirFlying]

I suspect that most pilots flying with a GFC autopilot have a WAAS-capable GPS navigator. And if they do, they will see an advisory glidepath (+V) when flying most 2D (nee non-precision) approaches. Newer GTN Xi variants provide +V guidance even when you fly a VOR approach (bruceair.wordpress.com/2021/05/14/vor-approaches-with-lnavv/). My practice and recommendation is to follow the advisory glidepath and use the point at which that +V guidance takes you to 50-100 ft above the MDA as the decision point--i.e., where you begin the missed approach. I'll try to get fresh video of a 2D approach one of these days. In the meantime: kzbin.info/www/bejne/p4iUdWiXiNKMfqM

[@greymarck]

In the beginning of this video you appear to be utilizing a PC simulation of the GFC 600. I've been unable to find one that ideally works with the Garmin PC Trainer, or even with a flight simulation that accurately simulates all of the modes and functionality available. What software are you using in this video? Thanks!

[@BruceAirFlying]

I am not aware of any simulation of the GFC 600 or GFC 500 autopilots. To help explain the features I was using, I captured images from the free Garmin PC Trainer Suite for Windows and photos of the GFC 600 controller. www8.garmin.com/support/download_details.jsp?id=12373

[@waltermengden8927]

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