Weather

Weather is composed of a number of elements such as the temperature and humidity of the air, atmospheric pressure, the speed and direction of the wind, air visibility and of special phenomena such as fog, storms and others.

Pilots need the information about weather conditions along the route of flight and at the destination aerodrome. The object of the meteorological service is to contribute to safety, efficiency and regularity of air traffic.

There exist some sources of aviation weather information: surface observation, radar observation, automatic meteorological observation, pilot reports and others.

At every airport there is a meteorological station which is equipped with special instruments recording all changes in the atmosphere. They indicate air pressure and temperature, record wind speed and direction as well as the movements of clouds. All the observations are summed up on special weather charts. The observations at the airports are made every 30 minutes and every 15 minutes if the weather suddenly gets worse or better.

Preparing for the flight the pilot is to get the latest weather information and weather forecasts along the planned route and at the point of destination and the alternates.

At agreat number of met. stations situated along the airways complete weather observations are made and then transmitted to weather forecast centres by telephone, telegraph, radio and thousands of miles of teletype circuits. Thus, the pilot has a complete picture of the weather.

20-30 minutes before entering the aerodrome area the controller gives the pilot full information about the terminal weather. At many airports the information helpful for landing and take off is continuously broadcast on a navigational aid frequency. Prior to descent the pilot requests the actual weather and aerodrome conditions for the airport he is going to land.

It is considered that landing of an aircraft is probably the most difficult operation which a pilot has to perform and the standards of visibility required are higher than for any other phase of flight.

It is known that fog, rain and clouds often affect the aircraft operation. For many decades attempts were made to make flying independent of weather conditions or, in other words, to allow an aircraft to land under very low or zero visibility.

Now there exist several categories set up by ICAO:

Category I - 200 ft ceiling and 1/2 mile visibility;

Category II- 100 ft ceiling and I/4 mile visibility;

Category III - landing under zero-zero conditions.

Met. services for aviation require much work to collect data and prepare weather charts. This work is especially difficult for long-distance flights over vast areas with different climatic conditions.

Nowaday met. services for aviation are almost fully automated. Automated Surface Weather Systems are installed at the airports of many countries. The System provides for the measurements, processing and display of the following meteorological parameters: wind direction and speed, air temperature and dew point t°, runway visual range, minimum cloud height, barometric pressure.

The use of lazers makes it possible to give pilots all the necessary information when they land under low visibility conditions. The introduction of these systems has greatly increased the reliability and safety of flights.

Satellite meteorology has become an independent area of science. Weather forecasts based on information from outer space make forecasts more accurate and help to save a great sum of money annually.

At present the work of meteorologist becomes easier thanks to computers which make calculations quicker and due to them the weather forecast service is becoming more reliable. The use of satellites and computers greatly increases the accuracy of weather forecasts.

Exercises

I. Ответьте на вопросы:

1. What elements are included in weather report?

2. What is the object of meteorological service?

3. How often is weather observation made at the airport?

4. What do the instruments at the meteorological stations indicate?

5. What weather information does the pilot get before the flight?

6. Do the pilots obtain weather information while in flight?

7. When does the controller give the pilot full information about the terminal weather?

8. What phase of flight does especially depend on weather conditions?

9. What weather phenomena affect the aircraft operation?

10. What categories are set up by ICAO?

11. What does Automated Surface Weather System provide?

12. When do lazers help the pilots?

13. What is the advantage of satellite meteorology?

14. What other instruments make weather forecast service more reliable?

II. Переведите слова, обращая внимание на словообразующие элементы:

direct – direction

visual – visually – visibility

observe – observation – observer

equip – equipment

transmit – transmission – transmitter

regular – regularity

depend – dependence – dependent – independent

provide – provision

accurate – accurately – accuracy – inaccurate

rely – reliable – reliability – unreliable

III. Найдите в тексте эквивалент следующим словосочетаниям:

сводки погоды, погодные условия, давление воздуха, скорость ветра, направление ветра, нижняя граница облачности, прогноз погоды, центр прогнозирования погоды, прогностические карты, станция обеспечения полета, погода аэродрома посадки

IV. Переведите на английский язык:

1. Погода состоит из таких элементов как температура и влажность воздуха, атмосферное давление, скорость и направление ветра, видимость.

2. Дождь, гроза, туман, шторм и другие явления опасны для полета.

3. Перед полетом пилот идет в метеобюро, чтобы получить сводку погоды и прогноз не только по своему маршруту, но и в пункте назначения.

4. В каждом аэропорту есть метеостанция со специальными приборами, регистрирующими все изменения в атмосфере.

5. Имея все данные о погоде, синоптики составляют погодную карту.

6. Во многих аэропортах информация о погоде непрерывно транслируется на определенной частоте.

7. Посадка самолета – самая трудная операция.

8. Стандарты видимости для посадки выше, чем для любой другой фазы полета.

9. Сейчас большинство метеостанций почти полностью автоматизированы.

10. Автоматическая система погоды показывает скорость и направление ветра, температуру воздуха, точку росы, дальность видимости на полосе, высоту облачности.

11. Прогноз погоды, полученный со спутников, делает его точнее.

12. Использование спутников и компьютеров повышает точность прогноза погоды.

Дата добавления: 2015-03-29