AIRCRAFT CLASSIFICATION

The word aircraft is defined as any weight-carrying device capable of being supported by the buoyancy of the air such as lighter-than-air aircraft (LTA acft); or by the dynamic action of the air, such as heavier-than-air aircraft (HTA acft). This definition includes balloons, dirigibles, gliders, helicopters and airplanes.

HTA acft are called glis, hels, or airplanes, or in some cases GMs. Originally, a gli has no motive power and depends upon air currents for its power. Airplanes, hels, and msls are engine driven. Airplanes are also termed winged or fixed-wing acft while hels are called bladed or rotary-wing acft.

Rotary-wing acft are supported by rotors of two or more blades and have no propellers to create forward push or pull. The rotors provide both lift and horizontal motion. The hel can rise and descend vertically, fly backward, sideways, forward or hover over one point.

Fixed-wing acft are most widely used. They are usually described according to the type of landing gear (landplanes, seaplanes and amphibian planes), type and number of engines (jet-powered and propeller-driven; single- or multi-engine) and wing arrangement. Airplanes with one main wing called monoplanes; those with two wings, one above the other, biplanes. The location of the monoplane's wing vertically with respect to the fuselage designates it as a low-wing, mid-wing or high-wing. Jet planes usually have swept wings or delta wings.

Рис.1.Wing configuration and shape:

1 - span - размах крыла; 2 - high-wing monoplane - моноплан с высокорасположенным крылом; 3 - shoulder-wing monoplane - моноплан с высокорасположенным крылом и подкосами; 4 - midwing monoplane - моноплан со среднерасположенным крылом; 5 - low-wing monoplane - моноплан с низкорасположенным крылом; 6 - triplane - триплан; 7 - upper wing - верхнее крыло; 8 - middle wing - среднерасположенное крыло; 9 - lower wing - нижнее крыло; 10 - biplane -биплан; 11 - sesquiplane - полутороплан; 12 - low-wing monoplane with cranked wings (inverted gull wings) -монопланс низкорасположенным крылом типа “обратная чайка”;13 - elliptical wing - эллиптическое крыло; 14 - rectangular wing -прямоугольное крыло; 15 - tapered wing - трапециевидное крыло; 16 - crescent wing серповидное крыло; 17 - delta wing треугольное крыло; 18 - swept-back wing with semi-positive sweepback - стреловидное крыло с полуположительной стреловидностью; 19 - swept-back wing with positive sweepback - стреловидное крыло с положительной стреловидностью; 20 - ogival wing -крыло оживальной формы

Recent developments in aeronautics have brought to life the vertical and/or short takeoff and landing(V/STOL) and the variable-sweep wing (or swing-wing) acft.