Aircraft components

Transportation. High performance fibers and high technology textile products have many appHcations ia the transportation area. Composites are increasingly used as stmctural materials ia aircraft components such as horizontal stabilizers, fins, landing gear doors, fan blades, and nose spia cones. 

Baker, A.A., Bonded Composite Repair of Metallic Aircraft Components — Overview of Australian Activities, AGARD (Advisory Group for Aerospace Research and Development) Conference of Composite Repair of Military Aircraft Structures, 3-5 October 1994, Seville. 

There are several suppliers of electron accelerators suitable for remote repair of composites, including Varian, Siemans, and Schonberg. At present, the only manufacturer of suitable portable electron accelerators is Schonberg Radiation Corporation of Santa Clara, California. Field repair of damaged aircraft components can be accomplished with a remotely controlled, truck-mounted accelerator. Table 13 gives the characteristics for several electron accelerators, all portable, supplied by Schonberg. Fig. 5 shows a schematic layout of a 10-MeV accelerator... 

The technology to routinely cure applied adhesives for repairing damaged composite structures at remote repair stations is currently available. There are already systems that use portable accelerators for X-ray radiographic inspection of aircraft components [43]. Fig. 6 shows a conceptual picture of a portable accelerator unit that would contain the power unit, vacuum systems, and computer... 

Paint strippers may give rise to hydrogen entry into steel, and in critical applications, such as the treatment of aircraft components, commercial paint strippers should be tested before use. 

The primary and secondary aluminum industry produces ingots of pure (greater than 99%) aluminum that serve as feedstock for other materials and processes. Within the U.S., the leading end-users of aluminum come from three industries containers and packaging, transportation, and building and construction. Examples of materials produced with aluminum are sheet metal aluminum plate and foil rod, bar, and wire beverage cans automobiles aircraft components and window/door frames. 

The wastewater at an aircraft-component manufacturing plant contained free and emulsihed oil. The water was treated using 454 kg of organoclay followed by a reverse-osmosis system. The organoclay portion of the treatment train cost 5000. The organoclay was replaced once a year. Replacement and disposal costs was approximately 3000 (D17267S, p. 30). 

The need for thermal stability of jet fuels is based on the following facts. In supersonic flight, the aircraft is subjected to high temperatures. This heat must be removed. Most convenient solution, in many types of jet aircraft, would be to use the fuel as a heat sink for cooling vital aircraft components, such as engine oil... 

Polyaryl sulfones are injection moldable or extrudabie on standard processing equipment. These plastics are used for meter housings, light fixture sockets, aircraft components, household appliances, hardware, and film. 

In 1937 rivets containing a small explosive charge in their shanks were constructed (Aircraft Factory Heinkel and Rheinisch-Westphalische Sprengstoff A. G. [131]). The composition of the explosive mixture is so selected that a slight explosion occurs on heating the head of the rivet with a hot iron. The explosion causes an expansion of the shank thus fixing the rivet in place. Explosive rivets have found wide application primarily for riveting aircraft components in which rivets are not accessible from both sides of the riveted surface. 

Pentoses contained in hemicellulose are used to produce furfural, a useful industrial chemical, used as a solvent for resins and waxes and in petrochemical refining. It is also used as a feedstock for a range of aromatic substances (it has an almond odour) including preservatives, disinfectants and herbicides. Furfural can be converted to furfuryl alcohol and used to make resins for composite applications with fibreglass and other fibres. These are of interest in the aircraft component and automotive brake sectors. Furfural is commercially derived from acid hydrolysis of waste agricultural by-products, such as sugarcane bagasse, com cobs and cereal brans. Around 450 000 tonnes is produced by this method per year. 

Epoxy-phenolic adhesives were developed primarily for bonding metal joints in high-temperature applications. Their first major application was to join major aircraft components. They are also commonly used for bonding glass, ceramics, and phenolic composites. Because of their relatively good flow properties, epoxy phenolics are also used for bonding honeycomb sandwich composites. 

Corrosion may be monitored by measuring changes in thickness with time using ultrasonic thickness gages. An automated ultrasonic inspection system has been devised and used in monitoring corrosion in nuclear waste containers and typical variations in ultrasonic indications in corroded and uncorroded areas have been recorded successfully. Major types of equipment inspection by ultrasonic technique has been done in mill components, power equipment, jet engine parts, aircraft components, railway materials, automotive components and other machinery components. 

It is a well-known fact that failure of an aircraft component can have catastrophic consequences such as loss of precious life and aircraft. It is obvious from Table 7.3 that failures due to fatigue are predominant in aircraft components. When the component is no longer able to withstand the imposed stress, failure will occur. Thus failures are associated with stress concentrations which can occur due to ... 

Vinyl lacquers are used mainly where a high degree of chemical resistance is required these lacquers are based on vinyl chlorides and vinyl acetates. Acrylic lacquers are based on methyl methacrylate and methyl acrylate polymers and copolymers. Other esters of acrylic and methacrylic acid also may be used to make nonconvertible film formers. Judicious selection of these acrylic acid or methacrylic acid esters allows one to produce film formers with specifically designed properties such as hardness, flexibility, gloss, durability, heat, and chemical resistance. Acrylic lacquers, however, are not noted for their water resistance. The principal uses of acrylic-type lacquers are fluorescent and metallic paints, car refinish applications, clear lacquers and sealers for metals, and protective coatings for aircraft components and for vacuum-deposited metals, as well as uses in pigmented coatings for cabinets and appliances. 

Applications in aircraft also increased very quickly. In 1959 Boeing reported from 150 to 200 applications of solid-film lubricants in B-52, KC-135 and Boeing 707 aircraft without any unserviceability reports, and the applications included critical aircraft components. By 1966 over 1000 applications of solid-film lubricants were reported on the North American B-70, and many of these involved molybdenum disulphide. Applications on the General Dynamics F-111 included the heavily-loaded variable geometry wing pivot. 

In Table 15.3 are shown the chemical structures and Tg and of some representative thermoplastic polymers for use at high temperature (3,9). These matrices have high continuous service temperatures (120-200° C) even under wet environmental conditions. Advantages of thermoplastic over thermoset matrices are their shorter fabrication cycle (generally controlled environment storage is not required) and the possibility to be reprocessed and reconsolidated after manufacture. Poly(ether ether ketone) is a strong contender with epoxy resins for use as a matrix in composite prepregs with carbon fibers to be utilized in structural aircraft components. 

An aircraft component factory for the Plessey organization, to be built in a three-mile length of completed but unopened Central Line tube tunnel between Wanstead and Gants Hill stations in East London. 

Three further proposals emerged the following year. In mid-April the Air Supply Board informed the Treasury that they intended to build an underground factory of 250,000 square feet at Drakelow near Kidderminster, into which it was intended to transfer some vital part of an aircraft component factory. No end user was specified, a MAP memorandum noting that ... 

---