时间:2011-03-11 23:18来源:蓝天飞行翻译 作者:航空 点击:次
paint dryer. A component, usually an oil, added to a paint to improve its drying characteristics. paint stripper. A material used to remove paint from a surface. Paint stripper contains very strong solvents in a wax-like vehicle which prevents the solvents from evaporating before they can soak into the paint film. Most paint strippers soften a lacquer film, so it can be wiped off. But rather than softening a film of enamel, the stripper penetrates it and causes it to swell. When the film swells, it wrinkles and breaks away from the surface on which it is applied. The wrinkled enamel is then scrubbed from the surface or washed off with steam or hot water. palladium. A soft, ductile, steel-white, tarnish-resistant metallic chemical element. Palladium’s symbol is Pd, its atomic number is 46, and its atomic weight is 106.4. Palladium is used in the manufacture of electrical contacts, jewelry, and surgical instruments. Pal nut. The registered trade name for a thin, pressed-steel nut which has a shallow cup-shaped bottom surface. A Pal nut is screwed down over the top of a plain nut to lock the nut onto a stud. When the Pal nut is tightened, the bent-up threads are forced down, so they hold pressure on the plain nut and prevent its vibrating loose. pan-pan (urgency signal). The international radio-telephony urgency signal. When repeated three times, pan-pan indicates uncertainty or alert, followed by the nature of the urgency. pancake landing (aircraft operation). A landing in which the aircraft is flared out (leveled off) several feet above the surface of the ground. As the aircraft loses its forward speed and aerodynamic lift, it drops to the ground in a flat attitude. panhead screw (aircraft hardware). A machine screw or sheet metal screw that has a large-diameter head that is slightly crowned, or rounded, on top. pants (airplane wheel covers). A commonly used name for the streamlined wheel covers installed on some fixed landing gear airplanes. |