
skydiving.ppt
- Количество слайдов: 13
parachuting (skydiving)
PLAN: § Vocabulary § Definition § History § Rules § My personal attitude
Vocabulary: § § § § Descent – спуск, снижение; Velocity –скорость, быстрота; Aircraft –авиация; Capsule (cell) –капсула, отсек; Supple – запас; Altitude –высота над уровнем моря; Range – предел; Feet – фут; Cord – веревка, шнур; Chute – парашют, стремнина; Ram-air parachute –гидравлически воздушный парашют; Glider – планёр; Miles per hour (mph) – миль в час.
Definition: parachuting device that slows the vertical descent of a body falling through the atmosphere or the velocity of a body moving horizontally. The parachute increases the body's surface area, and this increased air resistance slows the body in motion.
History: Dating to the 1100 s of the Chinese using parachutes for amusement. In the West, however, parachutes were originally conceived for human use as a means of providing a safe escape from a burning building. It was. Leonardo Da Vinciwho first proposed this use in 1483. The first person to demonstrate the use of a parachute in action was Louis-Sebastien Lenormandof France in 1783.
Rules: Typical jump altitudes in modern times for experienced skydivers range from 7, 500 to 15, 000 feet above ground level, yielding a freefall time of between 40 and 85 seconds. The length of the freefall is dependent upon such factors as exit altitude, opening altitude and fall rate. The fall rate is determined by the jumpsuit the skydiver wears and the way in which the suit conforms to the body during the freefall and by the diver's body configuration relative to the ground.
Rules: Freefall speeds for skydivers falling “belly to earth” range from 110 to 130 miles per hour The altitude at which a. parachutist opens the canopy varies, but 2, 500 feet is usual. With most parachutes, the skydiver pulls a cord that releases the pilot chute, a small chute opened by air resistance that acts to pull the main parachute out from the bag in which the parachutes are encased.
Rules: § For tandems and AFF, approximately 45 -60 seconds before deploying your parachute between 3, 000 and 5, 000 feet above the ground. § On an Accelerated Freefall (AFF) jump, first-time students learn to skydive with their own parachute system, experiencing the thrill of freefall with two instructors at their side—not attached to them. AFF requires four to five hours of intense ground instruction, including learning body flight maneuvers and hand signals that instructors use to coach the student as they fly alongside. He then makes a solo canopy descent, with radio instruction to help guide him to a safe landing.
RULES Reminder signals § • Height control: the thumb and forefinger locked in a so called "ring. " § • Simulation of chute opening all fingers clenched in a fist. § • Open parachute (immediate opening): extended index finger. Correction signals: § Flex: thumb down. § Relax hands, index finger and little finger; resembling a bull with 2 horns § straighten his legs, straightened index and middle fingers in the shape of the letter «V» . § Bend the legs: bent index and middle fingers. § Relax: swing relaxed wrist several times, or the instructor can shake a harness. § OK: thumb up.
Rules: The main parachute increases the skydiver's air resistance and slows the diver's fall to the ground to a speed of around 10 mph. Modern ramair parachutes are made of seven to nine nylon cells that inflate and act as a wing, or glider; these canopies allow the parachutist to steer and sail gently to the ground.
Tandem skydive § Many people make their first jump with an experienced and trained instructor – this type of skydive may be in the form of a tandem skydive. During the tandem jump the instructor is responsible for emergency procedures in the unlikely event that they will be needed, therefore freeing the student to concentrate on learning to skydive.
My personal attitude: In my opinion, parachuting is very dangerous and extreme sport, but very interesting.
skydiving.ppt