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pitch,in aviation: see airplaneairplane,
heavier-than-air vehicle, mechanically driven and fitted with fixed wings that support it in flight through the dynamic action of the air.
..... Click the link for more information. ; airfoilairfoil,
surface designed to develop a desired force by reaction with a fluid, especially air, that is flowing across the surface. For example, the fixed wing surfaces of an airplane produce lift, which opposes gravity.
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pitch:see tar and pitchtar and pitch,
viscous, dark-brown to black substances obtained by the destructive distillation of coal, wood, petroleum, peat, and certain other organic materials. The heating or partial burning of wood to make charcoal yields tar as a byproduct and is an ancient method for the
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pitch,in music, the position of a tone in the musical scalescale,
in music, any series of tones arranged in a step-by-step rising or falling order of pitch. A scale defines the interval relationship of each tone to the others upon which the composition depends.
..... Click the link for more information. , today designated by a letter name and determined by the frequency of vibration of the source of the tone. Pitch is an attribute of every musical tone; the fundamental, or first harmonicharmonic.
1 Physical term describing the vibration in segments of a sound-producing body (see sound). A string vibrates simultaneously in its whole length and in segments of halves, thirds, fourths, etc.
..... Click the link for more information. , of any tone is perceived as its pitch. The earliest successful attempt to standardize pitch was made in 1858, when a commission of musicians and scientists appointed by the French government settled upon an A of 435 cycles per second; this standard was adopted by an international conference at Vienna in 1889. In the United States, however, the prevailing standard is an A of 440 cycles per second. Before the middle of the 19th cent., pitch varied according to time, place, and medium of musical performance; since the classical period the trend has been gradually upward. The relative pitch of a tone, in contrast to absolute pitchabsolute pitch,
the position of a tone in the musical scale determined according to its number of vibrations per second, irrespective of other tones. The term also denotes the capacity to identify any tone upon hearing it sounded alone or to sing any specified tone.
..... Click the link for more information. , is an expression of its pitch in relation to the pitch of some other tone taken as a standard.
a readily melting, bituminous substance, insoluble in water.
Light and black pitch are distinguished. Black pitch is a product of the processing of ligneous or coal tars; it is used in the production of compound filler in shoe manufacture.
Light pitch is composed of rosin, petroleum oils, paraffin, wax, and several other substances; it is used to impregnate fibers in shoe manufacture and also in the production of putties, particularly gardening putty, which is used to cover grafts and wounds caused by pruning or damage to trees. Gardening putty keeps the injured areas in plants from drying out and protects these areas from water, air, bacteria, fungi, and insects.
the residue from the distillation of coking, semicoking, shale, pyrolytic, or other resins, and also of peat tar or wood tar. It is a solid (sometimes thick and viscous) black mass with a conchoidal fracture upon impact. It is plastic under a constant load.
A distinction is made among coal pitch, peat pitch, wood pitch, and petroleum pitch, according to the initial material. Coal pitch is composed predominantly of macromolecular aromatic hydrocarbons; it also contains higher phenols and organic bases. The insoluble fraction of pitch contains 8–30 percent free carbon, depending on the softening point; 0.2 percent and more ash; and asphaltenes. The density is 1.2–1.3 g/cm3.
Pitch is not electrically conductive. It is insoluble in water (peat and wood pitch contain small quantities of water-soluble substances) but soluble in many organic solvents, such as pyridine and benzene; it is resistant to acids. Pitch is mainly used in the preparation of electrode (ash-free) coke, as a binder in the briquetting of solid fuels, as waterproofing material, in the manufacture of tar paper and roofing felt, and in the preparation of varnishes for dyeing metal structures.
D. D. ZYKOV
the angular motion of an aircraft or vessel relative to the principal lateral axis of inertia. The pitch attitude is the angle between the longitudinal axis of the aircraft or vessel and the horizontal plane. In aviation, two types of pitch are distinguished: pitch with an increase in the pitch attitude and pitch with a decrease in the pitch attitude. Each is controlled by use of the aircraft’s elevators.
ii. The distance a propeller will advance in one revolution if there is no slip. Also called a propeller pitch.
iii. The angular setting of a helicopter main or tail rotor blade relative to the axis of rotation and measured at a defined station.
iv. The rotation of a camera about the axis parallel to the vehicle's lateral axis. Also known as a tip.
v. The distance between the centers of adjacent rivets installed in the same row. The distance between rows of rivets is called a gauge.
vi. The distance moved forward in one revolution by a screw. Also known as the pitch of a screw.