Steering the Green Mountain Head.

A tangent this time:  The Green Mountain Head.  This is a stake race that takes place in Putney, Vermont, USA every fall.  In Boston it’s quite popular, not only because it’s a good warmup for the fall racing season, but also because it’s just plain fun.  And the post-race lunch is pretty superior, in my estimation.  Their website is http://www.rowgmh.com/ just in case you’re interested. 

There is always a lot of discussion about the best way to take the turn at GMH, since it consists of two large buoys a mile and a half from the start/finish line.  I’d like to present what I think is an efficient way to do the turnaround. 

The first thing to realize is that your boat has a minimum turning radius.  It doesn’t really, because you can turn on a dime; but that would involve stopping dead and doing a river turn, which is not efficient time-wise.  Instead, what most scullers do is to row almost to the buoys and begin their turns by taking longer strokes on the side away from the buoys (starboard, in this case) so as to angle their boats toward the buoys (port, in this case).  At some point they check the boat down on port and lean to that side to rotate the boat around that squared-and-buried blade while they furiously row arm-and-back on starboard.  Once pointed perpendicular to the racecourse, they pick it up again full slide for a couple of strokes and repeat the process to complete the u-turn and head back toward the finish/start line. This procedure represents a good compromise between speed and turning radius. 

The thing is, if you get right up next to the first buoy to start your turn, you’ll end up traveling farther past the turnaround than if you took the turn a little wider.  I’ll show you what I mean.  Imagine this is your turning arc, minimized as above: 

Now, imagine that these are the buoys:

You have to choose where to start your turn, which means you have to choose where to place that arc relative to the buoys.  Let’s say you want to hug the first buoy (the one on the right, here, as you’ll be traveling from right to left as you turn).  That would look something like this:

Taking this path results in traveling the following distance past the buoy line, represented by the black arrowed line: 

Now, however, imagine that instead of approaching the buoy and trying to turn just next to it, you plan to set up for the turn a little wider, like this:

 

Now let’s draw another arrowed line to represent how far past the buoy line you travel: 

Let’s compare the lengths of those lines.  (I made these diagrams in Word, so all I did was to ungroup the objects, copy each little line, and paste the copies next to each other – I didn’t draw new ones or change their lengths).  They represent how far past the buoy line you travel.  Remember, it’s a distance you want to minimize. 

The extra distance past the line that you travel when you start your turn really close to the first buoy is on the left; the extra distance past the line that you have to travel when you take the turn a little wider is on the right.  And the distance on the right is less than the distance on the left. 

The first time I tried that race I actually got “beat” to the buoy by another sculler.  I was a little disappointed that I couldn’t get far enough ahead of her to take the inside of the turn, and ended up having to set up wide for the buoy line.  Imagine my delight, then, when I snuck right by in between her and the buoys after our turn, and made in back onto the straightaway before her.  Ha! 

Once you understand that your boat has a minimum turning radius, and that you have to carefully consider where to place the arc of your path, it makes you think differently about a lot of different corners or turns.  In the case of the Green Mountain Head, I think it makes sense to try setting up for the turn a little wide.  You travel less far past the turnaround line, and you have the satisfaction of passing people who haven’t read this blog. 

Comments

[hlp]

Very interesting. This kind of set-up for a turn is similar to what ski racers do--at least in the old days when the gates didn't hinge down when you hit them. You set the turn up early, and it actually shortens the overall distance you need to travel from gate to gate.