Former

Lore & Background

Formers are used in the construction of aircraft fuselage, of which a typical fuselage has a series from the nose cone to the empennage, typically perpendicular to the longitudinal axis of the aircraft. The primary purpose of formers is to establish the shape of the fuselage and reduce the column length of stringers to prevent instability. Formers are typically attached to longerons, which support the skin of the aircraft. The former-and-longeron technique was adopted from boat construction and was typical of light aircraft built until the advent of structural skins, such as fiberglass and other composite materials. Many of today's light aircraft, and homebuilt aircraft in particular, are still designed in this way. A former may become an integral part of the finished structure, as in an aircraft fuselage, or it may be removable, being used in the construction process and then discarded or re-used. Disposable formers are also used in strip-built boat construction, where some formers may be incorporated as structural ribs, and in civil engineering, bridge building, and architecture, where arches may be built upon a wooden former that is removed once the keystone is securely in place.

Reader's Guide

The significance of formers in aircraft construction lies in their dual role: they establish the complex curvature of the fuselage and structurally stabilize the stringers by reducing their column length. This former-and-longeron technique, adopted from boat construction, was the standard for light aircraft until the introduction of structural skins like fiberglass and composites. Despite the shift to modern materials, the technique remains in use for many light aircraft and homebuilt aircraft today. The article notes that formers may be either permanent, becoming an integral part of the finished fuselage, or temporary, used during construction and then discarded or re-used. This flexibility extends beyond aviation: disposable formers appear in strip-built boat construction (where some may become structural ribs) and in civil engineering and architecture, where wooden formers support arches until the keystone is set. The article does not provide dates, specific aircraft models, or named inventors, but it establishes formers as a foundational component in traditional aircraft design, still relevant in contemporary homebuilt aircraft.

Did You Know?

• A typical fuselage has a series of formers from the nose cone to the empennage, perpendicular to the longitudinal axis.
• Formers may be removable and discarded or re-used after construction.