时间：2011-03-11 23:11来源：蓝天飞行翻译 作者：admin 点击：次
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— the blade is twisted. blade wrench (propeller maintenance tool). A paddle-like tool with an airfoil-shaped cutout that is slipped over the propeller blade. A handle on the blade wrench is used to apply a twisting force to the blade. Blade wrenches are also called blade beams. blanket method of aircraft covering. The method of installing fabric on an aircraft structure in which the fabric is applied in the form of a sheet, or blanket, wrapped around the structure and fastened by sewing or cementing it in place. The other method of installing fabric is the envelope method, in which the fabric is sewed into the form of an envelope and slipped over the structure. The ends are then secured by sewing or cementing. blast fence. A barrier installed on an airport to divert or dissipate jet or propeller blast. bleed air. Compressed air taken from one or more stages of the compressor of a gas turbine engine. Bleed air is used for anti-icing, deicing, cabin pressurization, and cabin heating or cooling. bleed orifice. A calibrated orifice, or hole, used in some fluid power systems to allow a controlled flow of fluid while the system is in operation. When the system is shut down, all of the pressure bleeds off through the bleed orifice. bleed valve (gas turbine engine). A valve in the compressor case of an axial-flow gas turbine engine that allows some of the air to bleed off. By bleeding off some of the pressure, the airflow through the engine is improved, and there is less danger of compressor stall or surge. bleeder (composite structure component). A material such as glass cloth or mat placed over a composite layup to absorb the excess resin that is forced out of the ply fibers when pressure is applied. bleeder current. A steady current that flows from the output of a power supply through a bleeder resistor to ground. Bleeder current improves the voltage regulation of a power supply. bleeder resistor (electrical circuit component). A high-resistance resistor placed between the output of an electrical power supply and ground. The function of a bleeder resistor is to draw a fixed current for improved regulation, or stabilization, and to bleed off high-voltage charges from the capacitors when the equipment is shut off. bleeding brakes (maintenance procedure). A maintenance procedure in which air is removed from the hydraulic fluid in an aircraft brake system. Air in the fluid will compress when the brakes are applied, and the brakes will feel spongy and will not be effective. To bleed the brakes, a bleeder hose is installed in the brake cylinder, and fluid is pumped through the system until no trace of bubbles appears in the fluid. bleeding dope. Aircraft finishing materials containing certain types of pigments that bleed through any finish applied over them. Bleeding dopes can sometimes be successfully covered with a coat of aluminum-pigmented dope applied before the final topcoats. blemish. A visible imperfection that damages an object or destroys its value. |
