ET 
| 
UJ 
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REVIEW 
In aerial survey, navigation methods and equipment can be used 
for at least three different purposes: 
1. General air navigation, 
IN being the technique of guiding the 
| aeroplane to the starting point of the 
survey line or survey block,and return 
to the airport 
d Innovations and improvements in the field of general air navigation 
  
  
are: ) 
use of improved VLF navigation 
2) 
use of improved Doppler navigation 
| anh ed) QA 
use of improved INS navigation 
  
2. Survey navigation, 
being the technique of producing the correct coverage, 
which can be & pattern of parallel lines or any other 
pattern. 
Methods applied in survey navigation are 
(24) visual and/or DR 4) navigation methods 
(2b) instrumental navigation methods — either ground-based 
or selfcontained. : 
(2a) Innovations and improvements in the field of visual navigation 
or "contact navigation" are: use of ERTS/Landsat imagery for 
  
small and medium scale navigation. | e» 
Innovations and improvements in the field of D.R. navigation 
are: use of programmable pocket calculators N I One! 
(2b) Innovations and improvements in the field of instrumental 
d lii navigation are: use of doppler-plus-compass navigators and of 
| inertial navigators equipped with dedicated digital computers 
e numerical displays) the programs of which are designed 
  
rvey_navigation. 
  
I 1) 
I Doppler/compass/digital computer, precision self-contained 
| automated navigation equipment 
Very low frequency ground-based air navigation equipment 
Inertial navigation instrumentation, equipped with specialized 
navigation computer 
  
I 3) 
4) 
  
Deduced reckoning