When It Comes to Fletches, Size Does Matter

By Bob Robb

Arrow fletches do several things. They provide weight to the rear of the shaft, which helps balance it against the weight of the broadhead, creating the proper FOC (Front of Center) weighting needed to keep an arrow flying straight and true. The primary function of fletching, however, is to stabilize the shaft in flight by creating drag as the arrow flies through the air. They can also force the shaft to rotate through the air, though the rate of rotation is dependent on many things.

For many years we were told the amount of air drag caused by fletches was dependent on size and shape. Longer fletches equaled more air drag, while shorter fletching created less drag. But we’ve learned there is more to it than that.

When it comes to stabilizing modern broadhead-tipped arrows using plastic fletching, you’ll find that the overall length of each individual fletch is not nearly as critical as the stiffness and the height of the fletching. This is why when you go into your local archery shop, instead of seeing the three- and four-inch fletches so popular just five years ago, you’ll see much smaller stuff, such the 2.3-inch Duravane, the 2.1-inch Fusion, the 2-inch New Archery QuikSpin and the 2-inch Bohning Blazer vane, among others.

Why is this important? Older vanes were built thinner than today’s stouter versions. Though I do not have the ultra-high speed photography to back it up, I believe that the old longer fletching is more prone to “flapping” when flying through the air at high speed. With slower arrow speeds—it wasn’t all that long ago that most compound bows were launching shafts around 250 fps—air resistance isn’t as violent. These are the conditions in which longer fletching provides superb air drag and arrow control.  But with modern bows and carbon arrows, you are going to be shooting a much faster arrow. Today’s shorter, thicker vanes do not “flap” nearly as much, and in fact have come very close to eliminating this characteristic. And as a bonus, the shorter vanes optimize fletch clearance through traditional prong-type arrow rests, as well as the popular “biscuit” rest style.

There’s more. Fletches that are a bit rough on their surface, as opposed to slick and shiny, offer more air drag, which in turn aids in stabilization. This is easy to visualize when you think of the old turkey feather fletching, which experts say produces about twice the amount of air drag as equal-sized plastic vanes. The reason for this can be attributed to a feather’s surface, which is rough and full of natural slits that cause more air resistance or drag than a slick plastic vane surface. Thus, some companies intentionally rough up the surface of the vanes a bit. New Archery Products’ QuikSpin vanes, for example, were not only designed to spin the arrow faster but also incorporate micro-grooves on one side that promote rigidity and allow the air to pass through one side more easily as the rough side “grabs” to produce more drag. This creates greater arrow stability—even at that critical moment when the arrow immediately leaves the bow—and severely reduces flapping. 

Share |



Enter your comments below, they will appear within 24 hours

Your Name

Your Email

Your Comment

No comments yet, be the first to leave one below.