IFR BC Approach

[Paul Sharp]

Here’s something interesting that others may have already gone through, but it was a new experience for me, and I’m posting it in case it’s helpful for other pilots.

I have a Garmin 430. I am IFR rated and keep current, etc. I had read about practicing with the IFR GPS boxes before using them and have done a lot of practicing with the thing in the years since I had it installed, but usually the more common types of approaches. And it happens that most of the time in the past few years I find myself in VFR conditions.

A couple of months ago I ended up going IFR to Boise. And interestingly, they assigned me the LOC BC 28L approach. Never had one of those ever before except once during initial IFR training years ago, but I plugged it into the Garmin and flew the approach. I found it interesting that the readouts for distance weren’t very intuitive. They are labeled by Jeppesen with waypoint ID’s that don’t necessarily correlate easily with the chart. Fortunately, with radar required and ATC looking over things it went fine. But I had questions in my mind about the approach.

I called Garmin about 4 times since then going over this approach and asking questions about how it works in connection with the GPS. It took that many calls to get clear answers out of their technical support. One guy seemed quite knowledgeable and the other one seemed to have to ask the other one about it. Still it took a while to narrow down the details. If you have your nav tuned to IBOI (the localizer – 111.1) then you might think you’d see DME readouts of IBOI, corresponding to the chart’s stepdown fixes. But not so. Jeppesen has created a waypoint for each stepdown fix and you see the readouts to each as you approach it. And if you don’t know the naming and how the waypoint names correspond to the chart you can be doing more heads-down than is good. True, you can review the approach fixes as soon as you load it, and that’s something I think I’ll be doing more of in the future. But you’d still have to get it fixed in your mind what those identifiers are on this type of approach.

If you select the “vectors” transition, you won’t see some of the fixes loaded, but only from the FAF inward. So that can also be confusing if you don’t connect the dots on what is or isn’t loaded ahead of time. And you can’t practice this one with the downloaded simulator on a PC because the latest database is still too out-of-date to include the fixed on this approach. I think you could practice it on the GPS itself in the aircraft in simulator mode, but that often may not be very practical.

I suspect that other similar approaches are treated in the same manner. It proves to me what has been said about the need to practice with these boxes is very valid. You don’t’ want any guesswork while coasting down the final approach course in the soup. I’ve been flying too many straight-forward ILS approaches lately, I think. Many of the flight instructors I’ve flown with don’t know as much about the box as I do, so you can’t necessarily count on them helping in your reviews or training.