Comparing Modes of Transport

To understand how helicopters work and also why they are so complicated to fly, it is helpful to compare the abilities of a helicopter with those of trains, cars and airplanes. By looking at these different modes of transportation, you can come to understand why helicopters are so versatile!

If you have ever been inside of the cab of a locomotive, you know that trains are fairly simple to drive. After all, there are only two directions that a train can travel in forward and reverse. There is a brake to stop the train's travel in either direction, but there is no steering mechanism of any kind on a train. The tracks take the train where it needs to go.

Because a train has only two directions in which it can travel, you can drive a train with one hand.

A car, of course, can go forward and backward like a train. While you are traveling in either direction you can also turn left or right:

To handle the steering, a car uses a steering wheel that the driver can turn clockwise or counterclockwise. It is possible to drive a car with one hand and one foot.

Anyone who has taken pilot lessons or looked inside the cockpit while boarding a jumbo jet knows that planes are a lot more complicated to fly than a car is to drive. However, a plane is really only one step away from a car:

A plane can move forward and turn left or right. It also adds the ability to go up and down. However, it loses the ability to reverse. So a plane can move in five different directions instead of a car's four directions. The ability to go up and down adds a whole new dimension to a plane, and this dimension is one of the things that makes airplanes different from a car. To control the upward and downward motion of the plane, either a joystick replaces the steering wheel or the steering wheel gains the ability to move in and out (in addition to turning clockwise and counterclockwise). In most planes (but not all), the pilot also has access to two pedals to control the rudder. Therefore, a pilot could fly a plane with one hand and two feet.

A helicopter can do three things that an airplane cannot: A helicopter can fly backwards. The entire aircraft can rotate in the air. A helicopter can hover motionless in the air.

In a car or a plane, the vehicle must be moving in order to turn. In a helicopter, you can move laterally in any direction or you can rotate 360 degrees. These extra degrees of freedom and the skill you must have to master them is what makes helicopters sol exciting, but it also makes them complex.

To control a helicopter, one hand grasps a control called the cyclic, which controls! the lateral direction of the helicopter (including forward, backward, left and right). The] other hand grasps a control called the collective, which controls the up and down motion of the helicopter (and also controls engine speed). The pilot's feet rest on pedals that control the tail rotor, which allows the helicopter to rotate in either direction on its axis. It takes both hands and both feet to fly a helicopter!

The signature of a helicopter is its ability to hover over one point on the ground. While hovering, a helicopter can also spin on its axis so that the pilot can look in any direction.

LESSON # 4

AIRCRAFT CARRIER

Comparing Modes of Transport - student2.ru

Two aircraft carriers, USS John The Russian aircraft carrier Kuznetsov.

C. Stennis

(left), and HMS Illustrious (right), showing the---

Difference in size between a supercarrier and a light V/STOL aircraft carrier.

An aircraft carrier is a warship designed to deploy and recover aircraft—1 feet acting as a sea-going airbase. Aircraft carriers thus allow a naval force to project air power great distances without having to depend on local bases for land-base craft. Modern navies that operate such ships, treat aircraft carriers as the centerpiece of the fleet, a role previously played by the battleship. Unescorted carriers are considered vulnerable to attack by other ships, aircraft, submarines or missiles and therefore travel as part of a carrier battle group. In many navies, especially the United States Navy, И aircraft carrier is a capital ship.

Flight deck configuration

Modem aircraft carriers have a flat-top deck, the flight deck that serves as a take-off and landing area for aircraft. Aircraft take off to the front, into the wind, and land from the rear. Carriers steam at speed, for example up to 35 knots (65 km/h), into the wind during take-off in order to increase the apparent wind speed, thereby reducing the speed о the aircraft relative to the ship. On some ships, a steam-powered catapult is used to propel the aircraft forward assisting the power of its engines and allowing it to take off in a shorter distance than would otherwise be required, even with the headwind effect of the ship’s course. On the carriers, aircraft do not require assistance for take off — the requirement for assistance relates to aircraft design and performance. Conversely, when landing on a carrier, some aircraft rely upon a tailhook that catches on arrestor wires stretched across the deck to bring them to a stop in a shorter distance than normal. Other aircraft utilise their hover capability to land vertically and so require no assistance in speed reduction upon landing.

The primary function of the angle deck landing area is to allow aircraft who miss the arresting wires, to become airborne again without the risk of hitting aircraft parked on the forward parts of the deck. The angle deck also allows launching of aircraft at the same time as others land.

Comparing Modes of Transport - student2.ru

The above deck areas of the warship (the bridge, flight control tower, engine exhausts and so on) are concen­trated to the starboard side of the deck in a relatively small area called an "island". Very few carriers have been designed or built without an island.

A more recent configuration, used by the Royal Navy, has a 'ski-jump' ramp at the for­ward end of the flight deck. This was developed to help launch VTOL (or STOVL) aircraft (air­craft that are able to take off and land with little or no forward movement) such as the Sea Har­rier. Although the aircraft are capable of flying vertically off the deck, using the ramp is more fuel efficient. As catapults and arrestor cables are unnecessary, carriers with this arrangement reduce weight, complexity, and space needed for equipment.

During the Second World War, aircraft would land on the flight deck

parallel to the long axis Я of the ship's hull. Aircraft which had already landed would be parked on the deck at the bow end of the flight deck. A crash barrier was raised behind them to stop any landing aircraft which overshot the landing area because its landing hook missed the arrestor cables. If this happened, it would often cause serious damage or injury and even, if the crash barrier

was not strong enough, destruction of parked aircraft.

An important development of the 1940s was the British invention of the angled

deck, where the runway was canted at an angle of a few degrees across the ship. If an aircraft misses the arrestor cables, the pilot only needs to increase engine power to maximum to get airborne again and will not hit the parked aircraft because the angled deck points out over the sea.

As now only nuclear powered carriers have boilers as part of their motive power system, the majority of aircraft carriers are now equipped with steam generating plant solely to power the catapults. USS Enterprise was the first aircraft carrier to be powered in this way and subsequent super carriers took advantage of this technology to increase their endurance.

The post-war years also saw the development of the helicopter with different capa­bilities to a fighter aircraft. Whereas fixed-wing aircraft are suited to air-to-air combat and air-to-surface attack, helicopters are used to transport equipment and personnel and can be used in an anti-submarine warfare role with dipped sonar and missiles.

Aircraft carriers are generally accompanied by a number of other ships, to provide protection for the relatively unwieldy carrier, to carry supplies, and to provide addi-

tional offensive capabilities.

WORDLIST:

Aircraft carrier - авианесущий корабль, авианосец

sea-going airbase - морская авиационная база

naval force - военно -морские силы

land-based aircraft -самолеты наземного базирования

battleship -линейный корабль, линкор

carrier battle group -авианосная боевая группа

capital ship -корабль основного класса; линкор

flat-top deck, flight deck - полетная палуба

apparent wind speed -относительная скорость ветра

steam-powered catapult - паровая катапульта

tailhook - посадочный гак (хвостовой)

arrestor wire -(трос) аэрофинишер(а)

angle deck landing area - угловая посадочная палуба

flight control tower - авиационный диспетчерский пункт

engine exhaust - дымовая труба

starboard - правый борт

port side -левый борт

island,superstructure - надстройка

'ski-jump' ramp - (трамплинный) взлетный пандус

bow end -носовая часть, нос

lower hold -трюм

crash barrier - аварийное тормозное устройство

nuclear powered carrier - авианосец с ядерной силовой установкой

steam generating plant - паропроизводительная установка

fighter aircraft - самолет-истребитель

air-to-air combat - воздушный бой

air-to-surface attack - (удар) атака наземных целей

endurance - автономность плавания;

дальность плавания

personnel - личный состав

anti-submarine warfare - противолодочная война(борьба)

dipped sonar - погружной гидролокатор, эхолокатор

missile - управляемая ракета

COMMENTARY:

to deploy and recover aircraft— размещать и обслуживать самолеты. Unescorted carriers are considered vulnerable to attack by other ships, aircraft, submarines or missiles and therefore travel as part of a carrier battle group.- Неохраняемые авианосцы рассматриваются как потенциальные цели для ударов, наносимых кораблями, авиацией, подводными лодками или управляемыми ракетами (противника) и поэтому действуют только в составе авианосных групп.

A crash barrier was raised behind them to stop any landing aircraft which overshot the landing area because its landing hook missed the arrestor cables. - Аварийное тормозное устройство поднималось за ними (самолетам), чтобы остановить любой самолет, совершивший посадку с перелетом, так как посадочный гак не зацепил трос аэрофинишёра.

to increase engine power to maximum to get airborne - увеличить до максимума обороты двигателя, чтобы самолет остался в воздухе.

EXERCISES:

I. Give equivalents to the following words and word combinations:

Aircraft carrier,взлетать вертикально, capital ship, личный состав, submarine, flight control tower, надстройка, angle deck, носовая часть, ship's hull, вертолёт, aircraft design, линкор, flight deck, landing hook, воздушный бой, starboard side,

вертикальный взлет и посадка.

II. Translate the following sentences into Russian:

a) A crash barrier was raised to stop any landing aircraft which overshot the landing

area.

b) Aircraft carriers are generally accompanied by a number of other ships, to pro­vide protection.

c) The pilot only needs to increase engine power to maximum to get airborne

again.

d) The bridge, flight control tower, engine exhausts are located in the superstruc­ture.

e) The angle deck also allows launching of aircraft at the same time as others

land.

f) Aircraft utilise their hover capability to land vertically and so require no assis­tance in speed reduction upon landing.

g) A steam-powered catapult is used to propel the aircraft forward assisting the

power of its engines.

h) Aircraft take off to the front, into the wind, and land from the rear.

i) Modern navies that operate such ships, treat aircraft carriers as the centerpiece

of the fleet

III. Translate the following information into Russian:

A surface ship generally consists of the hull, decks and superstructure. The interior of a ship is divided into compartments (rooms, cells or bays) by bulkheads. The keel,| running fore-and-aft throughout her length, is the backbone of the ship. The deck below is called the second deck, then comes the third and so on. The part of a ship above the main deck is the superstructure. It extends from side to side of the ship and usually mounts masts supporting radio and radar antennas, engine exhaust and other equipment In the aircraft carriers the superstructure is positioned away from centerline to permit take-off and landing of aircraft. The front of a ship is the bow; the rearmost part is the stem. Her right side is the starboard; her left side is the port. Ships are driven by propellers and steered by the rudder.

Like other warships aircraft carriers are built of mild steel. The vessel has two skins or bottoms. The inner and outer bottoms are connected together by two systems of frame - longitudinal and transverse, which subdivide the double bottom into watertight cells.

The American aircraft carrier, nuclear-powered USS Nimitz has a flight deck on which there are four steam catapults.

Below the flight deck are the hangars where aircraft are stored. These decks are connected by elevators for the rapid movement of aircraft upwards. Below these decks are the engine rooms, living quarters, repair shops, lower hold and many other cells.

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