Реферат про самолеты на английском
Обновлено: 05.07.2024
1 The Noise Problem
Though long of concern to neighbors of major airports, aircraft noise first became a major problem with the introduction of turbojet-powered commercial aircraft (Tupolev 104, Boeing 707, Dehavilland Comet) in the late 1950s. It was recognized at the time that the noise levels produced by turbojet powered aircraft would be unacceptable to persons living under the take-off pattern of major airports. Accordingly, much effort was devoted to developing jet noise suppressors, with some modest success. Take-off noise restrictions were imposed by some airport managements, and nearly all first-generation turbojet-powered transports were equipped with jet noise suppressors at a significant cost in weight, thrust, and fuel consumption.
The introduction of the turbofan engine, with its lower jet velocity, temporarily alleviated the jet noise problem but increased the high-frequency turbomachinery noise, which became a severe problem on landing approach as well as on take-off. This noise was reduced somewhat by choosing proper rotor and stator blade numbers and spacing and by using engines of the single-mixed-jet type.
2 Effects Of Noise
Noise is often defined as unwanted sound. To gain a satisfactory understanding of the effects of noise, it would be useful to look briefly at the physical properties of sound.
Sound is the result of pressure changes in a medium, caused by vibration or turbulence. The amplitude of these pressure changes is stated in terms of sound level, and the rapidity with which these changes occur is the sound's frequency. Sound level is measured in decibels (dB), and sound frequency is stated in terms of cycles per second or Hertz (Hz). Sound level in decibels is a logarithmic rather than a linear measure of the change in pressure with respect to a reference pressure level. A small increase in decibels can represent a large increase in sound energy. Technically, an increase of 3 dB represents a doubling of sound energy, and an increase of 10 dB represents a tenfold increase. The ear, however, perceives a 10-dB increase as doubling of loudness.
Another important aspect is the duration of the sound, and the way it is distributed in time. Continuous sounds have little or no variation in time, varying sounds have differing maximum levels over a period of time, intermittent sounds are interspersed with quiet periods, and impulsive sounds are characterized by relatively high sound levels and very short durations.
The effects of noise are determined mainly by the duration and level of the noise, but they are also influenced by the frequency. Long-lasting, high-level sounds are the most damaging to hearing and generally the most annoying. High-frequency sounds tend to be more hazardous to hearing and more annoying than low-frequency sounds. The way sounds are distributed in time is also important, in that intermittent sounds appear to be somewhat less damaging to hearing than continuous sounds because of the ear's ability to regenerate during the intervening quiet periods. However, intermittent and impulsive sounds tend to be more annoying because of their unpredictability.
Noise has a significant impact on the quality of life, and in that sense, it is a health problem. The definition of health includes total physical and mental well-being, as well as the absence of disease. Noise is recognized as a major threat to human well-being.
The effects of noise are seldom catastrophic, and are often only transitory, but adverse effects can be cumulative with prolonged or repeated exposure. Although it often causes discomfort and sometimes pain, noise does not cause ears to bleed and noise-induced hearing loss usually takes years to develop. Noise-induced hearing loss can indeed impair the quality of life, through a reduction in the ability to hear important sounds and to communicate with family and friends. Some of the other effects of noise, such as sleep disruption, the masking of speech and television, and the inability to enjoy one's property or leisure time also impair the quality of life. In addition, noise can interfere with the teaching and learning process, disrupt the performance of certain tasks, and increase the incidence of antisocial behavior. There is also some evidence that it can adversely affect general health and well-being in the same manner as chronic stress.
2.1 Hearing Loss
Hearing loss is one of the most obvious and easily quantified effects of excessive exposure to noise. Its progression, however, is insidious, in that it usually develops slowly over a long period of time, and the impairment can reach the handicapping stage before an individual is aware of what has happened.
Prolonged exposure to noise of a certain frequency pattern can cause either temporary hearing loss, which disappears in a few hours or days, or permanent loss. The former is called temporary threshold shift, and the latter is known as permanent threshold shift.
Temporary threshold shift is generally not damaging to human’s ear unless it is prolonged. People who work in noisy environments commonly are victims of temporary threshold shift.
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Сочинение на английском Самолет / Essay on Plane
I think we are very lucky to live in the 21 st century. Thanks to new technologies a lot of exciting things are available to us, about which people could only dream of a hundred years ago.
Actually the first successful controlled and sustained airplane flight took place in the beginning of the 20 th century. But that was only a test flight and first jets were unsafe.
During the 20th century great progress was made in the field of aviation. By now all the big cities have airports. Millions of passengers travel by air every day around the world.
Aircrafts are very safe now. Planes are even safer than cars. I know that some people have aerophobia, but their fear is very irrational. One takes more risks going to the airport by taxi, than flying in the aircraft.
I am not afraid of flights at all! It is so exciting that in a few hours you land in another city or even in another country. I love traveling so much. But usually we go to the sea only once a year. I wish we could do it more often. Traveling by aircraft is not extremely expensive, but it is not very cheap either. Especially if you need tickets for all family members.
Some people feel discomfort or pain it the ears during takeoff and landing. I only felt it once, when I had a runny nose. Usually I feel fine all the flight. Though I have never had a flight more than 4 hours long. I guess I would be tired of sitting for a longer period. There is not much space to limber up in the plane. But it is not such a big problem.
I hope in future I will visit a lot of countries. I’m happy to live in the time when flying is not a fairy tale anymore.
Я думаю, нам очень повезло, что мы живем в 21 веке. Благодаря новым технологиям нам доступно множество увлекательных вещей, о которых люди могли только мечтать сто лет назад.
На самом деле первый успешный управляемый и устойчивый полет самолета состоялся уже в начале 20-го века. Но это был всего лишь испытательный полет, и первые самолеты были небезопасны.
В течение 20-го века был достигнут большой прогресс в области авиации. Сейчас во всех больших городах есть аэропорты. Миллионы пассажиров ежедневно совершают авиаперелеты по всему миру.
Самолеты теперь вполне безопасны. Самолеты даже безопаснее автомобилей. Я знаю, что у некоторых людей есть аэрофобия, но их страх иррационален. Ехать в аэропорт на такси рискованнее, чем лететь на самолете.
Я совсем не боюсь полетов! Это так захватывающе, что через несколько часов вы приземлитесь в другом городе или даже в другой стране. Я так люблю путешествовать. Но обычно мы ездим к морю только раз в год. Жаль, что мы не можем делать это чаще. Путешествие на самолете не очень дорого, но и не очень дешево. Особенно если вам нужны билеты для всех членов семьи.
Некоторые люди чувствуют дискомфорт или боль в ушах во время взлета и посадки. Я почувствовал это только однажды, когда у меня был насморк. Обычно во время полета я чувствую себя прекрасно. Хотя у меня никогда не было рейса более 4 часов. Думаю, я устал бы сидеть дольше. В самолете не так много места для разминки. Но это не такая уж большая проблема.
Надеюсь, в будущем я побываю во многих странах. Я счастлив жить в такое время, когда полет больше не сказка.
на английском языке с переводом на русский язык
Traveling by Plane
Путешествие на самолёте
Our world lives in the situation of globalization. National and cultural borders are more transparent than before. People travel all over the world with different aims: to have a rest and see other countries (tourism), work (international business), and study (educational exchange). Sometimes one’s relatives and friends live abroad, so trips there become regular.
Наш мир живёт в ситуации глобализации. Национальные и культурные границы более прозрачны, чем раньше. Люди путешествуют по всему миру с разными целями: чтобы отдыхать и смотреть на другие страны (туризм), работать (международный бизнес) и учиться (образовательный обмен). Иногда чьи-то родственники или друзья живут за границей, и поездки туда становятся регулярными.
Of course, everyone needs a convenient and available way to travel for long distances. Some people prefer traditional trains, but not all the railways pass through state borders. Besides, traveling by train usually takes much time. As for traveling by sea, it also can be impossible (for example, between countries of the Central Europe) or cause poor health.
Конечно, каждому нужен удобный и доступный способ путешествовать на дальние расстояния. Некоторые люди предпочитают традиционные поезда, но не все железные дороги проходят через государственные границы. Кроме того, путешествие на поезде обычно занимает много времени. Что касается путешествий по морю, они тоже могут быть невозможными (например, между странами Центральной Европы) или вызывать плохое самочувствие.
Therefore, the most popular way to go abroad is traveling by plane. The plane is not the cheapest, but the fastest and the most comfortable transport vehicle allowing to cross continents and oceans just in a few hours. A traveler may choose a flight, buy a ticket and book a seat in advance, via the Internet. It is not necessary to carry a heavy suitcase, because the luggage is delivered separately, after the control of its weight and contents. Although the custom control procedures are rather long, they guarantee the safety of passengers during the flight.
Поэтому наиболее популярный способ ездить за границу – путешествие на самолёте. Самолёт – не самое дешёвое, но самое быстрое и комфортное транспортное средство, позволяющее пересекать континенты и океаны всего за несколько часов. Путешественник может выбрать рейс, купить билет и забронировать место заранее, через Интернет. Нет необходимости носить тяжёлый чемодан, так как багаж доставляется отдельно, после контроля его веса и содержимого. Хотя процедуры таможенного контроля довольно долгие, они гарантируют безопасность пассажиров во время полёта.
There is another point of view: some people suppose that traveling by plane is very dangerous. However, modern planes technically improved and equipped with all the protective means. Only highly qualified pilots and stewards can serve them. In my opinion, traveling by plane is safe and enjoyable.
Есть другая точка зрения: некоторые люди считают, что путешествовать на самолёте очень опасно. Однако современные самолёты технически усовершенствованы и оборудованы всеми защитными средствами. Только высококвалифицированные пилоты и стюарды могут обслуживать их. На мой взгляд, путешествия на самолёте безопасны и приятны.
What are the main structural components of the airplane?
A modern airplane has five basic structural components: the fuselage, the wing set, the empennage, power plant and the undercarriage. The fuselage is the main body to which all components are attached.
As for other components of a fuselage. The cockpit is a compartment where flight crews work. Doors and windows are built into the fuselage, including the windshield through which the pilots look to see where they are going. The wings are airfoils attached to each side of the fuselage. Ailerons are fitted at trailing edge of the wings. They are situated at the inner section of the wings. They are necessary to increase lift at lower speeds during take off and landing.
Other flap-like devices are slats. They are installed at the leading edge of the wings. Slats are designed to adjust the angle of attack. The winglets are placed on some airplane to reduce drag.
The empennage plays an important role in stability of an airplane. It includes vertical stabilizer, rudder and elevator.
As for lower part of the fuselage. There are power plants, engine cowlings, main gear and nose wheel. These parts of the fuselage are necessary for the following:
power plant – for generating thrust
engine cowlings – for creating the flow of air around the engines
main gear and nose wheel – are used during parking, taxiing, rolling and landing.
Современный самолет состоит из 5 основных компонентов: фюзеляж, крылья, хвостовое оперение, двигатель и шасси. Фюзеляж - это основная часть, к которой крепятся все детали.
Что касается остальных компонентов фюзеляжа, кабина пилотов - это помещение, где работает летный экипаж. Двери и окна встроены в фюзеляж, включая лобовое стекло, через которое пилоты могут наблюдать, где они летят. Крылья прикрепляются по обе стороны фюзеляжа. Элероны крепятся к задней кромке крыла. Они необходимы для увеличения подъемной силы на низких скоростях во время взлета и посадки.
Похожие на закрылки поверхности - это предкрылки. Они устанавливаются к передней кромке крыла. Предкрылки сконструированы, чтобы регулировать угол атаки. Винглеты расположены на некоторых самолетах для снижения аэродинамического сопротивления. Хвостовое оперение играет важную роль в поддержании стабильности самолета. Оно включает киль, руль направления и руль высоты.
Что касается нижней части фюзеляжа, там есть двигатели, капот двигателя, основная опора шасси и передняя стойка шасси. Части фюзеляжа необходимы для следующего:
- двигатели - для генерации тяги,
- капоты двигателей - для создания потока воздуха вокруг двигателей,
- основная опора шасси и передняя стойка шасси - используются при рулении, парковке, повороте и посадке.
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