Kite line
Kite lines perform various roles: bridle, control, tug, or special duty.
The integrity of kite lines is affected by wear, reeling, contact with chemicals, loss of strength from knottings, ultraviolet rays of the sun, repeated cycles of use, and damaging actions during use.
Reeling, handling, and storage methods differ for lines depending on the kite applications.
Depending on the kite application and kite system needs, selecting a kite line will consider one or more of the following parameters: availability, base material, color, density, mass per length, size, manufacturer's reports, serial number or product number, diameter, cross-section shape, tensile strength new, aged tensile strength, resistance damage from chemicals, defects, safety factor, resistance to damage from solar radiation (UV stabilization), electrical conductivity, optical conductivity, heat conductivity, moisture intake from water (via humidity, rain, contact with liquid water), buoyancy in water, abrasion resistance, nature of manufacturer's line joins, feel, degradation from knotting, terminal methods, elasticity, structure, signal transmission capacity, visibility to radar, performance over time, maintenance actions, effect on performance from hours of use, drag, negative lift, auxiliary line uses, performance when being reeled under tension, performance when tensed line touches itself, action upon breaking, memory, veil, sleeving, inspectability, surface finish, reaction to heat and cold, taper (as wanted), flexibility, reeling behavior, breaking strength, critical diameter, reliability, test-results portfolio, visibility, twist, plasticity, safety, price.
For example, the design and handling of the piano-wire kite line for the high-altitude meteorological observations (1749–1933) was a keen engineering process.
[10] Historically, high altitude kite flights were made by atmospheric scientists and meteorologists in the late 19th to early 20th centuries.
The line was over 20 km of high tensile steel piano wire with a breaking strength varying between 134 and 225 kg.
[11] In 2014 the single-line single-kite altitude world record was made using a kite line of Ultra High Molecular Weight Polyethylene (UHMWPE, Dyneema) with 300 pound breaking-strength.
The greatest barrier to high altitude kite flights is aerodynamic line drag.
[13] The use of Dyneema over an extended period has shown that it is highly resistant to ultra violet degradation in comparison to Kevlar.
The indoor no-wind kite operator need not worry about line breaks causing damages to downwind property.
Piano wire is appropriate for certain applications, but totally inappropriate for recreational or sport kite flying.
Fishing monofilament line is not used for most hobby, recreational, or sport power kiting because of its stretch, breaking behavior, and thinness; avoid it unless there is a very special application involved.
Gloves, proper reel choices, goggles, guards, tension limiters, and other safety devices help to reduce accidents.
