Friday, July 31, 2009

Simple NDB Approach

Two weeks since my last flight because the weather in the Northeast is still marginal. I guess I've been spoiled by flying in the Atlanta area. Yes, the weather gets ugly there too, but you can plan around the thunderstorm activity. Planning here is just impossible, so finding a good weather day is mere chance. Thursdays seem to work well for the current cycle.

Having spent so much time on the VOR approach with a holding entry, I wanted to see what the autopilot would do with an approach with a procedural turn. Quakertown (UKT) provides an NDB 29 (with GPS overlay) which includes some step downs along the way.

Preflight was normal, she needed some gas but the oil looked like it had recently been changed. The rest of the airplane looked good (I'm still thrilled to be able to fly a plane like this.) I finished my checklist and turned the key..and waited. No joy. What I should have known prior to start was that the airplane had been flown that day and was still warm...requiring the warm start procedure. Following the normal/cold start procedure flooded the engine. **Note to self, ask if the plane has flown when I pick up the key. Yes, the engine was warm when I checked, but I attributed that to sitting in the sun.

The rest of the ground procedures were normal and comfortable. I let the take off roll go too long, but otherwise the departure went fine. Setup and entry for the approach also went well. I am truly amazed at what the system can do. In the 'old days' I would perform the 5(I used 6) Ts: Time (for reporting purposes), Twist (CDI to outbound course), Turn (to the outbound course), Time (outbound for procedure turn), Transition (to new airspeed/altitude/or configuration), Talk (position report). While I audit those factors, the airplane is capable of aviating and navigating the approach entry hands off. The trick is being able to tell the airplane (through the GNS430) what you want it to do, and there are always a variety of ways to do that. My training is to understand all of those options and to understand the optimal use of the system at any given time.

So, once PT inbound I wait for the 'needle to come alive' to put the autopilot into Approach mode. Now I'm on the final approach course inbound and can make my first step down. How? There is no vertical guidance so I can set a vertical speed and automatic altitude capture, or just push the Alt button when I reach desired altitude. FAF requires a transition (half flaps) and descent to MDA. Again, options to be considered on how to do this with the various modes of the autopilot and I dutifully try each one. (CFII must be going nutz as he has told me this a dozen times, but my training requires me to make the mistake with each unsatisfactory option to fully understand the ramifications.) My rate of descent was too shallow so we missed and headed back for published holding.

A brief discussion about approach plates. Previously I would look down at my kneeboard and see the entire picture. Header, planview, minimums, etc, I would would cross check that plate a half-dozen times while on the approach. The chart function in the airplane has all of this information as well (and more), but it is divided into four views which can be displayed by cycling the view button. I'm getting comfortable with this but still lack efficiency. In this case I could have found and used the optimum vertical speed, but didn't...another lesson learned.

The training I've pointed out above is all secondary to the real key to controlling this technology; mastery of the GNS430. It is simply not good enough to have a basic understanding of some of the functions. This again became clear setting up for the 're do' approach from holding. Choosing the complete approach from Proc button (my choice) tells the airplane to do the whole approach with procedural turn, but realistically, if you're in holding already you don't want that. So understanding what options are available and where they can be found is vital if you expect to utilize the suite effectively.

This was a great exercise, the flight concluded with a GPS 24 back issues. I'm always delighted to fly by Willow Grove (NXX), a former 'stomping ground'. Landing was OK.

Time = 1.9 hours

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