Tuesday, December 19, 2017

We Must Sail to Apparent Wind

You can only sail to apparent wind, not the real wind.

This is one of the hardest things to teach about sailing. As the boat moves, the wind that affects the sail changes. And, although the effect is less, so do the currents flowing past the rudder.

Let's say the real wind is directly from north to south at 10 knots speed. A sailboat can't sail directly into the wind, but most boats can easily sail at a 45 degree angle to the wind. So we set our sail and as the wind flows over it we begin to move northeast, maybe at 5 knots "over ground" meaning over an imaginary fixed surface.

So just as you feel a breeze if you run or ride a bike on a still day, the moving boat feels a breeze coming from the northeast at 5 knots in addition to the wind from the north at 10 knots. Combined they act like a single breeze of nearly 14 knots from the north-northeast. And it is this wind for which the sailor must trim the sail and set the rudder. The real wind no longer matters except as one component of apparent wind.

Did I mention currents, as opposed to "over ground?" Its easy to sail fast (relative to the water beneath your bow) while being carried even faster in the opposite direction by the current.

One can easily understand that the apparent wind constantly changes in both speed and direction as the boat changes direction. And everything, literally everything, about sailing the boat, changes as well. Think about the example above. As the boat picks up speed it feels more wind, and will thus gain even more speed. And the apparent wind will shift direction as the speed increases, requiring a change in the rudder. At some point the sailor may even need to adjust the sail to actually slow down a bit or risking having the boat get blown over.

The most important point here, however, is that you simply cannot teach the theory of apparent wind and expect a new sailor to know how to sail. Not even sophisticated sailing simulation games can teach the sailor to sail. 

Real knowledge of sailing doesn't exist inside the head of the sailor. It exists in the deep connection between the sailor's body, the boat, the wind, and the water. This is why Patrick O'Brian's Captain Aubry is instantly recognizable as a real sailor while C.S. Forrester's constantly calculating and ever introspective Horatio Hornblower is a fascinating character but a landlubber's fantasy.

What is true of real and apparent wind is just as true of anything moving, including human organizations like a church moving through the social world. At some point the "real" social world being described by social analysts and demographics becomes less important, even irrelevant, compared to the world as it appears to a congregation in ministry to the people who come its door or to whom it reaches out.

And that is why you can't really know Christian ministry by going to school. All the theory in the world doesn't constitute actual knowledge. That comes only by leading the church, by becoming intimately linked to its people and the actual environment they experience in ministry. And what is true of the whole is true of the constituent parts, such as preaching, teaching, prayer, worship, and administration. You don't know what it means to lead a voluntary society until you've heard people say no to your suggestions or yes to your invitations.

Those people, like that homeless woman seeking a handout or the neighborhood children playing on the church lawn, or the city council ordinance changing the zoning of a neighboring lot are the "apparent wind" to which the church must sail. And you cannot know them until they are in your face.


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