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164 U.S. CIVIL AERONAUTICS AUTHORITY

Highways and roads. - To place dependence upon following roads is, in general, bad practice unless nothing better offers.

Aeronautical charts do not profess to show all roads, as that would be an almost impossible task requiring constant revision. It will be found that the roads on the latest charts are neither accurate, complete, nor up to date.  However, the charts do attempt to give the pilot the general road pattern for the vicinity, but it should be re-membered that new pavement is continually being laid and many new roads being constructed.

Different colored roads sometimes assume undue importance due to light conditions or the surrounding terrain.  For the same reasons they are often very hard to see.  Old stained concrete is not nearly as prominent as a freshly graded country road in certain colored soils.

In sections where there are few roads, a cross road properly iden-tified by the aid of other landmarks, will usually lead to a fair sized town, with the chance of finding a landing field near it.

In many parts of the United States roads are laid out around sections of land, with the result that they will found to generally run in a north-south or east-west direction.  This crisscross pattern can be a considerable aid in finding direction.

Do not get panicky if the roads shown on your chart do not conform exactly with those you see below you see. Look for other landmarks.

Rivers. - Rivers are usually excellent landmarks.  Like railroads, their presence below gives a feeling of confidence.  The curves of a winding river offer many good fixes.  However, pilots should remem-ber that they have their peculiarities, some of which are as follows: In flat woody country, rivers are sometimes confusing and hard to trace.  The water is sometimes had to detect through the trees unless the light is just right or unless they are directly below.  Some rivers have so many tributaries that it is very difficult to trace the main stream.  When a river is in flood, its appearance and area may be so changed that it will be unsafe to depend upon it.  After heavy rains, or during a flood season, water can sometimes be seen through the trees in many places when the light reflects upon it.

In the western areas, the chances are that the big river shown on the chart will turn out to be nothing more than a dry arroyo during most of the year.  It is only by careful examination of the topography of the surrounding country that the pilot is about to find traces of it.

When you are seemingly hopelessly lost, the direction in which a river flows will sometimes give you a key to where you are.

Lakes. - Except where there are too many of them, lakes generally offer good fixes.  As with rivers, in arid areas lakes also have a way of drying up completely and disappearing during certain seasons of the years.  There are sometimes small artificial lakes that have not been marked on the chart that show up well when the light hits them right.  In connection with with artificial lakes created as the result of hydroelectric projects it is well to remember these are being de-veloped rapidly, particularly in southern Sates, and they may not be shown on the chart.

In is well to remember that on sectional charts, lakes are very often shown much larger than they really are, in order to vie the general