I love feathers. Dating back to my boyhood, birds in flight were a source of wonder. As I've grown older my fascination with feathers has never diminished. Now, as a bowhunter, I appreciate them even more. Feathers have properties so perfectly suited to archery that one might believe they were designed for the back of an arrow rather than for the wing of a bird. Maybe this is so. If domestic turkeys no longer fly, then why do they still need feathers? Why haven't they lost them like Darwin said they would? To my one-track mind the reason is clear: They exist because archers still need them. 

Feathers are perfect for archers because they offer stiffness and rigidity where and when it is needed unlike plastic vanes that are the primary source of poor rest clearance.

I studied the anatomy of the feather while in veterinary school. I was amazed by the simplicity of its design that was starkly contrasted by the complexity of its structure. Every flight feather has two vanes, one on either side of the main stem. Each vane consists of many barbs in a parallel row. Each of these barbs has several hooks on the front and a rounded flange on the back. The hooks on the front of one barb hook onto the flange on the back of the adjacent barb, locking them together. If they are unhooked, they can be reattached simply by stroking the feather.

This interlocking system gives the feathers tremendous lateral strength. Push sideways on a feather and you'll see what I mean. This lateral stability is the primary reason that feathers correct poor arrow flight so quickly. The feather provides stiff resistance as the arrow fishtails or porpoises. Plastic vanes, on the other hand, have very little lateral strength. They fold over easily, providing little resistance to the side pressures encountered when an arrow is not launched perfectly.

While feathers resist crushing along one plane they seem to shy away from it on another. Much to the archer's benefit, feathers have almost no linear support. Push down on a feather fletching and it flattens right out. If a feather encounters an obstacle while in flight (such as the arrow rest) it simply folds down, creating very little flight disturbance. A plastic vane, on the other hand, has too much linear support. If it crashes into the rest it wreaks havoc on the arrow's flight.

On average, plastic vanes weigh four times as much as feathers. Big deal you say? If arrow speed is a concern it is a big deal. Hunting arrows do the best job of combining stability with a flat trajectory when they have a balance point that is 10 percent or greater forward of center. Every grain of weight you can remove from the back of the arrow allows you to remove a corresponding amount from the front of the arrow without significantly changing its (Forward of Center (FOC)) balance point.

For example, if you replace four-inch vanes with four-inch feathers you remove 25 grains from the back of the arrow.

You can now remove 25 grains from the front of the arrow without significantly changing the balance point. The arrow is now fifty grains lighter and correspondingly faster. 

The Half-Empty Glass

I hate feathers. I've tried repeatedly to quit them. I believe I can quit at any time if I really want to, but I guess just saying that confirms my hopeless addiction. Even deep denial can't change the fact that, though reluctantly at times, I'm a feather-aholic. Yet, despite my proclivity toward using them, there are plenty of reasons to hate feathers.

They're noisy. They're noisy in the quiver and they're noisy in flight. Noise is a bowhunter's bane. Feathers collapse when they get wet. They lose their ability to steer the arrow. The broadhead takes over the controls and there's no telling where the Nolan Ryan knuckle ball will end up. Granted, there are now reasonably satisfactory ways to waterproof feathers, but when you face tough weather day after day they can still be a problem.

Feathers are fragile. Shoot feather fletched arrows into a bale of straw and push them back through; the feathers look like they've been through a paper shredder. You'll replace your feathers three times for every time you replace your vanes.

I try to force myself to use plastic vanes every couple of years, but the experiment is always short-lived. Each time I prove to myself that the problems feathers create are inconsequential when compared to the problems they solve. None of man's fabrications will ever adequately replace this marvel of nature. 

• Article reprinted with the permission of Bowhunter Magazine.