La cometa —también conocida con otros nombres (véase: nombres regionales, más abajo)— es un juguete y un deporte.
Es un artefacto volador más pesado que el aire (aerodino), que vuela gracias a la fuerza del viento y a uno o varios hilos que la mantienen desde tierra en su postura correcta de vuelo. Es un juego tradicional, pero también se realizan competiciones de cometas en las que participan principalmente adultos; desde 1980 se hacen concursos a la antigua usanza en los que intervienen cientos de concursantes.
Debido a su propia construcción lo habitual es desplegar las cometas en lugares abiertos y ventosos, como descampados o playas, etc.
Kites are tethered flying objects which fly by using aerodynamic lift, requiring wind, (or towing), for generation of airflow over the lifting surfaces.
Various types of kites exist, depending on features such as material, shape, use, or operating skills required. Kites may fly in air, water, or other fluids such as gas and other liquid gaining lift through deflection of the supporting medium. Variations in design of tethering systems and lifting surfaces are regularly introduced, with lifting surfaces varying in stiffness from limp sheet material to fully solid material.
Kites may be built by the flier or by a dedicated kite manufacturer, which may be a member of the Kite Trade Association International (KTAI), which also includes kite retailers.
Kites have been made from the following materials:
High aspect-ratio – wings that have a narrow chord (length from front edge to rear edge), compared with their span.
Kites are normally heavier than their supporting medium, such as a kite flown in air. Some kites have their lift augmented by lighter than air gases, allowing the kite to remain airborne without wind or being towed.
Hydro dynamic kites can have positive, neutral or negative buoyancy, relying on hydrodynamic lift to manoeuvre, rise, or dive.
Kites can be controlled by various methods which usually involve manipulation of the tether/control lines, lifting gas density control and in some cases by aero-dynamic control surfaces
Kites can have positive, neutral or negative stability, in all axes of control, in the same fashion as aircraft. Kites with positive stability tend to return to a stable state automatically, whereas those with neutral or negative stability require control inputs to return the kite to the required position or attitude.