Sunday, June 10, 2007

Back to Basics - Holding 101

Probably one of the weakest areas I see in working with both instrument students and instrument-rated pilots is holding. Granted, you don’t do it too often in the real world of IFR flying, but holds do come along on occasion.

In a previous article, Creating Holding Clearances, I talked about entries into holding patterns. But in this article, let’s step back even further and talk about how to draw a hold, given a holding clearance. Surprisingly, it’s an area that experience has shown me is lacking in basic understanding.

There are two broad categories of holds – published and unpublished. Published holds are drawn out for you on either an instrument approach plate or an enroute low chart. Unpublished holds are not depicted. They start with a holding clearance, and from there you are expected to translate that into the holding pattern. A holding clearance has a very definite form.

Hold [direction] of [waypoint] on the [radial or bearing] [direction of turns] [EFC]

So a hold around Gopher (GEP) VOR could be given as:

Hold northeast of Gopher on the 060° radial right-hand turns EFC

EFC is shorthand for “expect further clearance” and is a time limit, given in the event of loss of communications.

Once the holding clearance has been given, there is often a fair amount of confusion about the correct way to translate that into a graphic holding pattern. This is what I often see. The pilot will draw a line outbound from the VOR, hesitate, then draw the right hand turn at the “end” of the outbound leg. Then they will complete the pattern, which results in a left-hand holding pattern. This is how the incorrect holding pattern looks.

This all too common mistake results from confusion about where the “right hand” turn is defined. Here are the steps to drawing it correctly. Start at the VOR and draw a line outbound on the radial. Next reverse course and draw over the same line back in towards the VOR. Once you are back to the VOR, now draw the right-hand turn, and complete the holding pattern. It should look like this.

If you will follow this procedure, your holding pattern will be correct. The key point to remember is that the direction of turn, right or left, is drawn at the VOR, not out on the radial. Another key to help you get it right is to remember that when you track inbound, you want to be tracking inbound on the specified radial, with a heading that is the reciprocal of the given radial. Your outbound track is in the same direction as the given radial, but you are offset from the radial.

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