How to make a parachute?

Parachute is commonly known as "safety umbrella". Parachutes are widely used in the aerospace field, and their long-term use is: (1) emergency lifesaving. Mainly used to save the pilot's life when the plane crashes; (2) stabilizing effect. Keep the attitude of the aircraft ejection seat stable and the refueling machine of the aerial tanker stable; (3) slow down. The braking deceleration when the plane landed and the stagnation deceleration of various aviation bombs and parachutes. Parachute can shorten the landing glide from more than 2000 meters to 800 ~ 900 meters; (4) recycling. Used for air recovery of aircraft, such as unmanned aerial vehicles, test missiles, launch vehicle boosters, high-speed detectors and recoverable spacecraft. There are also recycling equipment on spacecraft and hot air balloon detectors; (5) air drop. Paratroopers airborne, all kinds of materials and weapons airdropped; (6) air movement. Such as skydiving, hillside gliding, hanging wing gliding, power flight, traction lift-off, etc. Classification and use of parachutes: parachutes are divided into three categories: human umbrellas, resistance umbrellas and object umbrellas. People's umbrellas are divided into life-saving umbrellas, paratroopers' umbrellas, coaches' umbrellas, sports umbrellas and spare umbrellas. According to the way of carrying-chest umbrella, back umbrella, sitting umbrella, resistance umbrella (deceleration umbrella). Material umbrellas are divided into throwing umbrellas, bomb umbrellas and recycling umbrellas. There are many kinds of parachutes with different uses, but they all require light weight, softness, high strength-to-mass ratio (strength/mass), certain elongation, high air permeability, high tear strength, flame resistance, aging resistance and mildew resistance. The main components of a parachute are a canopy, a guide umbrella, a rope, a strap system, an opening and an umbrella bag. It consists of textile materials such as umbrella silk (made of silk, cotton cloth and nylon fabric in the early days), umbrella rope, umbrella belt and umbrella thread, as well as some metal parts and rubber parts. Umbrella rope adopts hollow or braided rope with core, which requires compact structure, high strength, softness, good elasticity and small uneven elongation. The umbrella belt is used as the reinforcement belt and sling system of the umbrella clothing. Umbrella rope is the skeleton of umbrella clothing, which requires light weight, softness, high strength and high elastic modulus, less than the elongation at break of umbrella clothing fabric. The umbrella belt adopts double-layer or three-layer fabric thick belt, which requires high strength and breaking work. Umbrella thread is the connecting material for sewing umbrella thread, umbrella belt and umbrella rope, which requires high strength, good lubrication and even and stable twist. Life-saving umbrellas, including seat stabilizing umbrellas and life-saving umbrellas, are life-saving tools used to save the lives of off-board pilots in an emergency. This kind of textile material for umbrella not only conforms to the general parachute performance, but also has the characteristics of portability, softness, high breaking work, high tear strength and tensile strength, good air permeability, good flame resistance and good aging resistance. Parachute This is a stable deceleration tool for paratroopers in airdrop combat and parachuting training. It is one of the heaviest parachutes that people carry. In addition to human weight, you need to carry certain weapons and equipment. This kind of umbrella is required to be safe and reliable, suitable for heavy-duty and intensive skydiving, and has a certain protective color. This kind of umbrella requires sufficient strength of materials and proper permeability of umbrella clothing. The inflatable bag of umbrella clothing should be made of textile materials with light weight, good elasticity and floatability and high strength-to-mass ratio. Resistance Umbrella This umbrella is specially used for airplane landing with other braking devices, which can shorten the taxiing distance. This kind of umbrella is characterized by large dynamic load, small volume, light weight, reusable, poor environmental conditions and high temperature resistance. Therefore, the textile materials used can withstand drag, wear and high breaking strength on rough runways, and can still withstand large opening impact after repeated use, and must have good heat resistance, scorch resistance and high environmental aging resistance. Bomb parachute It is the general name for all kinds of aerial bombs (parachutes) dropped by air. The missile parachute must be safe and reliable, with good stability when the missile leaves the plane, ensuring a certain air time and meeting the tactical requirements. The dynamic load of opening the umbrella shall not exceed the allowable bearing capacity of the aeroelastic structure and its instruments, and the weight and volume of the umbrella shall be as small as possible, with good mildew-proof and moisture-proof performance. For umbrella fabric, it is required to meet the indexes such as breaking strength, elongation at break, air permeability and weight, as well as environmental adaptability, chemical resistance, aging resistance, sewing property, pressure resistance, resilience and flame retardancy. Parachute This is a parachute used to drop supplies and equipment. There are many kinds of air-dropped materials, and the weight varies greatly. Large items, such as trucks, cannons, tanks, etc. Therefore, the textile materials for umbrellas require high strength, light weight, good elasticity, good chemical stability, aging resistance, wear resistance, scorch resistance, sewing and packaging folding. The function of space recovery umbrella is to ensure that the recovered materials can return to the ground safely after completing the flight mission. In addition to the requirements of deceleration, stability, reliability and safe landing that general parachutes must have, it is also necessary to solve the problems of large overload, aerodynamic heat, particle radiation and packaging volume limitation. Therefore, there are special requirements for the strength-to-mass ratio, high temperature resistance and shooting resistance of textile materials for parachutes, especially the high temperature resistance and rocket launching height 126 km, the opening height of the arrow recovery umbrella 66 km, and the opening speed 1 100 m/s, so that parachutes can be applied to the recovery of rockets, missiles, spacecraft with arrows and other spacecraft. Because two-thirds of parachute materials are textile materials, the performance of parachute is closely related to textile materials, and the application of textile materials in aviation field has gradually formed a unique category. At first, the textile materials of parachutes were silk, long-staple cotton and high-quality hemp, which were later replaced by nylon yarns. With the emergence of aramid fiber Kevlar -29 fiber and ultra-high molecular weight polyethylene fiber, the performance of parachute has been continuously improved and strengthened. The performance of parachute fabric depends not only on the fiber material, but also on its fabric structure to a great extent. Most of them use plain weave and increase the warp and weft density, or add thicker yarns to the plain weave to form a lattice appearance on the fabric, so as to improve the strength and tear resistance of the fabric and improve the hand feel.