III. Match words from column A to their translation in column B

II. Discuss the questions about materials in small groups.

I. Look at the picture and discuss in pairs what materials are used for this aircraft. Each colour is different type of materials.

MODERN MATERIALS

UNIT 5

SENSORS

UNIT 4

1. Make a list of materials which are used in aircraft.

2. What is the most popular material being used in aircraft?

3. What are advantages and disadvantages of the material?

	A		B
	boron-reinforced	a	упрочненный ароматическим волокном
	metal fatigue	b	стекловолокно
	resin	c	материал на основе эпоксидной смолы
	aramid-reinforced	d	армированный бором
	fiber-reinforced matrix	e	смола
	fiberglass	f	усталость металла
	composite material	g	углеродное волокно
	epoxy	h	матрица, армированная волокнами
	carbon fiber	i	композиционный материал

IV. Read and translate the text. What do the following numbers refer to?

300; 2012; 1987; 2005; 350; 50; 787; 1960; 150; 35; 2013; 70; 211

Common composite materials used in aviation are fiberglass, carbon fiber and fiber-reinforced matrix systems, or a combination of any of these.

Composite material has been around since World War II. Over the years, composite material became more popular, being used in different airplanes and gliders. About 35 percent of the nation's aircraft structures were made of composites in 2005. Today, aircraft structures are commonly made up of 50-70 percent composite material.

Boeing rolled out its new 787 Dreamliner in 2012, boasting that it was 50% composite material. And in 2013, the A350-XWB, which is also made of at least 50% composite materials, took flight.

Most of the time, the use of composite materials on an aircraft structure reduces weight. Fiber-reinforced matrix systems are stronger than traditional aluminum found in most aircraft, and they provide a smooth surface and increase fuel efficiency.

Composite materials don't corrode as easily at other types of structures. They don't crack from metal fatigue and they hold up well in structural flexing environments. Composite materials also last longer than aluminum, which means fewer maintenance and repair costs.

Composite materials don’t break easily, but that makes it hard to tell if the interior structure has been damaged at all. Aluminum bends and dents easily and it's apparent if the structure has been damaged in any way; it's harder to tell with composites. Repairs can also be more difficult when a composite surface is damaged.

The resin used in composite material weakens at temperatures as low as 150 degrees, making it important for these aircraft to avoid fires. Fires involved with composite materials can release toxic fumes and microparticles into the air. Temperatures above 300 degrees can cause structural failure.

High cost can be associated with composite materials, but this cost is typically offset by long-term cost savings.

Composite materials have played a major part in weight reduction, and today there are three main types in use: carbon fiber-, glass- and aramid- reinforced epoxy; there are others, such as boron-reinforced.

Since 1987, the use of composites in aerospace has doubled every five years, and new composites regularly appear.

Composites are versatile, used for both structural applications and components, in all aircraft and spacecraft, from hot air balloon gondolas and gliders, to passenger airliners, fighter planes and the Space Shuttle. Applications range from complete airplanes such as the Beech Starship, to wing assemblies, helicopter rotor blades, propellers, seats and instrument enclosures.

The types have different mechanical properties and are used in different areas of aircraft construction. Carbon fiber for example, has unique fatigue behavior and is brittle, as Rolls Royce discovered in the 1960's when the innovative RB211 jet engine with carbon fiber compressor blades failed catastrophically due to birdstrikes.

Whereas an aluminium wing has a known metal fatigue lifetime, carbon fiber is much less predictable, but boron works well (such as in the wing of the Advanced Tactical Fighter). Aramid fibers are widely used in honeycomb sheet form to construct very stiff, very light bulkhead, fuel tanks and floors. They are also used in leading- and trailing-edge wing components.

Overall, carbon fiber is the most widely used composite fiber in aerospace applications.

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