Aerospace industry design

Probabilistic design methods have been shown to be important when the design cannot be tested to failure and when it is important to minimize weight and/or cost (Dieter, 1986). In companies where minimizing weight is crucial, for example such as those in the aerospace industry, probabilistic design techniques can be found. 

In the design of equipment for the manufacture of sterile ophthalmic (and nonophthalmic) pharmaceuticals, manufacturers and equipment suppliers are turning to the advanced technology in use in the dairy and aerospace industries, where such concepts as CIP (clean-in-place), COP (clean-out-of-place), automatic heliarc welding, and electropolishing have been in use for several years. As a guide here, the reader is referred to the so-called 3A Standards of the dairy industry issued by the U.S. Public Health Service [267],... 

Propellant compositions are also used in numerous "gas generator" devices, where the production of gas pressure is used to drive pistons, trigger switches, eject pilots from aircraft, and perform an assortment of other critical functions. The military and the aerospace industry use many of these items, which can be designed to function rapidly and can be initiated remotely. 

Serial No 693358) is seen as a simple improvement over die multi-component, mechanical assemblies normally used for one-way explosive-energy transfer. Typical one-way transfer devices rely upon mechanical functions and percussion.primers. Another assembled components design used in the Indus ry relies on the precise placement of boosters to assure that a predetermined schrapnel dispersement allows functioning in only one direction. Both have drawbacks that limit their usefulness in the aerospace industry... 

Far from being unique to the aerospace industry, model-based design and optimization are standard practice across a great many industries, including microelectronics, petrochemicals, and automobiles. All of these industries share four characteristics ... 

Dual-turbine or twin-turbine designs were developed for the aerospace industry, where much higher rangeabilities (up to 1,000 1) are needed than in industry. 

If both substrates to be bonded are nonconducting, then the adhesive formulation must contain a susceptor material. Susceptors can have a small percentage of magnetic iron oxide, iron filings, or carbon additives. A susceptor can also be a steel screen or perforated steel foil that is embedded in the adhesive bond line. It has been found that graphite fiber composites used in the automotive and aerospace industries are sufficiently conductive that they can be successfully heated with induction. Design considerations must be taken into account in placement of the graphite reinforcement, so that the material heats uniformly. 

Much of what we know about bonding to composite materials has come through the aerospace industries. The early studies on adhesives, surface preparation, test specimen preparation, and design of bonded composite joints reported for the PABST Program76 gave credibility to the concept of a bonded aircraft and provide reliable methods of transferring loads between composites and metals or other composites. 

The PMR range of resin materials utilize a two-step reaction, in which a norbornene-terminated prepolymer is formed in situ by the condensation reaction of low molecule weight diamines with norbornene-capped imides or acid esters [37]. The PMR-15 designation refers to polymerization of monomeric reactants, with a mixture of diaminodiphenylmethane and a dimethyl ester and a norbornene-containing monomethyl ester, to form a condensation prepolymer having molecular weight approximately equal to 1500. PMR resins are used as matrix materials in high performance composites in the aerospace industry. 

Physical prototypes are used for testing and evaluation of product properties in the early development stages of product development. VR permits testing and evaluation to be conducted in virtual prototypes. The objective is to avoid physical prototypes if possible. Research is being conducted in the automotive and aerospace industries (Leston et al. 1996). Apart from purely design-oriented tasks, efforts are also being made to conduct physical materials tests, such as crash tests, in virtual proto-... 

Specific tests in the aerospace industry include the assessment of humid atmospheres on physical and mechanical properties. In prEN 2823 [37] the normally used conditions are 70 C and 85% RH, although 95% RH is also available. Some users consider both these options are more severe than normal operating conditions and may unna esstirily penalize the material properties that can be used in design. ASTM D 5229 [38] specifically pro ides for measuring moisture uptake in polymer matrix eomposites. 

Advanced materials are undoubtedly one of the pillars on which the aerospace industry rests, as they can meet the pressing demands of designers for high performance in extreme environments. Material technology is the driving force in the development of space exploration (launchers, satellites, hypersonic vehicles), civil air transportation and military air defence, and its rapid evolution is as important as the advances in computer science or electronics, though less publicised. 

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