Flatbow

A flatbow is a bow with non-recurved, flat, relatively wide limbs that are approximately rectangular in cross-section. Because the limbs are relatively wide, flatbows will usually narrow and become deeper at the handle, with a rounded, non-bending handle for easier grip. This design differs from that of a longbow, which has rounded limbs that are circular or D shaped in cross-section, and is usually widest at the handle. A flatbow can be just as long as a longbow, but can be very short. (typical lengths would be say, 68-70" flatbow. 70-72" English longbow. 72-76" warbow weight English longbow, but these styles may easily overlap each other). Traditional flatbows are usually wooden self bows (bows made of one solid piece of wood), though laminated and composite flatbows have been made in ancient and modern times. Modern flatbows commonly use fiberglass.

The flatbow is a superior bow design for almost all materials because the stress is more evenly spread out than with rounded limb sections. A bow limb is essentially a flexed beam undergoing bending, and in any flexed beam the farther from the neutral axis (line in the middle of the flexing beam which is not under tension or compression: see diagram in Bending article) the more stress there is within the material. When a limb is rounded, as in a longbow, some material sticks out farther from the neutral axis, and thus is put under greater stress. In a flatbow, the flat belly and back ensure that all of the most strained material is a uniform distance from the neutral axis, spreading the load over a wider limb, minimizing stress and making weaker woods far less likely to fail (break or become permanently bent and lose the resilience needed in a bow). Only particularly resilient timbers can make an effective and powerful wooden longbow.

In most parts of the world, common hardwoods may be used to create excellent bows. Suitable and easily available timbers include elm (used in ancient Europe, as evidenced by bows pulled from European bogs), maple, sycamore, hazel, and ash. The flatbow design also lends itself to very dense, high strength woods such as hickory and especially osage orange (a wood favored by many Native American tribes for bow making). Good quality yew wood is still much more expensive and difficult to find than woods suitable for flatbows, and beginning bowyers are strongly recommended to start with a flatbow made from easily available wood. Because yew, the wood of choice for European longbows, is light, resilient, and has exceptional compressive strength, the rounded design can be used to produce a smooth shooting, efficient, powerful bow. This is economical of wood and of the bowyer's time.

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