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             LOW LEVEL NAVIGATION WITH RELATION TO GROUND ATTACK.

Introduction.

1.   Low level navigation may be described as any navigation carried out during
flight below 500' above, ground level. Since the average pilot spends most of
his time flying at much greater altitudes, it is not surprising that he is not
thoroughly familiar with the problems associated with accurate navigation close
to the ground.

Reasons for operational low flying.

2.   By flying low the pilot gives himself a very good chance of reaching the
target undetected. He is: -

     (a)  Below radar cover.

     (b)  A vary difficult sighting problem for other aircraft.
          A camouflaged Hunter, for example, is almost invisible from above
          when flying over European terrain.

     (c)  A difficult target for ground defences.
     
Problems of low level navigation.

3.   Field of Vision. When flying low the pilot's field of vision is restricted
and therefore the number of available pin-points is reduced. Over slightly
undulating terrain the field of vision from 100' is approximately one mile.
This means that the pilot need not be far off track for some of his main pin-
points to become obscured.

4.   There is a considerable difference between the field of vision. at 250' -
the peacetime low flying limit, and the "on the dock" conditions which would
prevail in war. It is as well to remember this when considering the degree of
accuracy required in flight planning, and also that flights in war will not be
over familiar ground in the local low flying areas.

5.   Recognition of pinpoints. When flying really low there is the difficulty
of recognising pinpoints presented in an entirely different perspective. A lake
or a wood, for example, easily recogniseable in plan from 2000', becomes of
doubtful value to the inexperienced when viewed as a blur of trees or water with
regular outline, with probably only a portion in view. The pilot must therefore
know what to look for and exactly when and where to look for it.

6.   Hazards. Another problem particular to the low level sortie is the amount
of lookout needed to ensure avoidance of high tension cables, wayward pheasants
and the like. This would obviously be a much greater problem in war with no
250' safety limit. The greater the lookout the less time available to "look in"
and check maps, flight plan, and stop watch.

7.   Weather. Unexpected bad visibility can often mar the sortie. Mist near
coastlines, smoke haze in the lee of large towns may prevent pinpoints from being
seen for some considerable time. By sticking to accurately planned courses and
times there is a very good chance of swiftly fixing one's position once these areas
have been passed.

8.   It must therefore be obvious that if low level sorties are to be conducted
successfully and safely, navigation must be efficient and as far as possible
automatic. This state can only be attained by constant practice, a thorough
knowledge of the problems involved, and application of the correct technique.

                                                              /Planning.

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