The effects of the weather on aviation

Except perhaps for local or very short flights, a pilot, before taking off, obtains a weather forecast giving him the weather conditions which are expected along the route of his flight and at his destination. Because weather conditions affect aircraft in flight, to a considerable extent, special aviation forecasts are provided by meteorologists at weather offices all over the world.

The meteorologist, or forecaster, prepares a weather chart which shows the current weather conditions over the whole country. The current weather chart is called a synoptic chart. This synoptic chart shows the areas of low pressure, the areas of high pressure, where precipitation is falling, and all other weather conditions across the country.

From this weather map, the forecaster can inform pilots of the weather conditions they can expect to encounter during their flights. A high pressure area, for instance, usually means good weather while a low pressure area usually involves one or more fronts producing clouds and precipitation over many hundreds of miles.

A pilot needs to know the wind direction and speed. A headwind will obviously delay the arrival of flights and is to be avoided if at all possible. A tailwind on the other hand, can be of great advantage as it increases the ground speed and results in a reduction in fuel consumption. Winds vary with altitude, and also from one place to another, so information on winds is very important.

Pilots will pay particular attention to a low pressure which lies en route, and the weather conditions associated with that low pressure area. The associated cold or warm fronts could involve clouds, thunderstorm, snow, rain, and turbulence. From his charts, the meteorologist can forecast where this weather will be at a certain time in the future, and with the help of these predictions, the pilot will decide which route to fly and when and he will know what weather conditions to expect. Should the forecast be very bad, for example, dense fog or poor visibility due to snow, the pilot may decide to postpone his flight. A pilot flying VFR would also cancel his flight because of low ceiling or low overcast conditions on route.

Air navigation

Air navigation came into existence alongside with air traffic. It had a humble beginning, but in a little more than 50 years has come today's extensive aircraft industry, a vast network of global airlines.

In the early days of flying, serious accidents often occurred because men were not thoroughly familiar with the new medium of transportation.

Today pilots are familiar with the construction of the aircraft, its controls, and its limitations. Competent instructors are available to give this information as well as to give actual flight instructions. The manuals are based not only on sound theory but also on long experience. They should be obtained and carefully studied.

The directing of aircraft from one place to another is the science of air navigation.

In fair weather and during daylight, it is usually not difficult to fly from one place to another by visual reference to landmarks noted in the charts. In bad weather and in the hours of darkness, the usual landmarks are often lost to view. Even the airport of the destination may be closed.

If air transportation is to function safely and with any degree of regularity, some aids to navigation, including instrument landing facilities, must be made available.

With the installation of instrument landing systems at principle terminals, and with other equipment such as radar and radar beacons, we may confidently expect that air transportation soon will become independent of all but the most severe weather conditions.