a 1985 ground preparation at a scale of 1/30000, with transfer 
on 1987 aerial survey. Adjustment results on control points are 
as follows 
- for planimetry 
- for altimetry 
0,75 i 
0,60 m 
  
what appears normal for transferred points at a scale of 1/30000 
1) Comparison between GPS positions and coordinates of the 
points of view. 
A first aspect concerns medium position of the whole block re- 
lative to the ground reference. Computation is done from diffe- 
rential data corrected from main GPS systematic errors : 
error of the satellites, ephemerid errors and, partly, ionos- 
pheric delays because the fixed receiver was far enough from 
the test flight. Distance between antenna and point of view, 
and geoid height relative to Clarke ellipsoIde are also correc- 
ted. In these conditions the translation for the whole block 
has the following components : 
Tx" -—3,02 m 
Ty 1.37 I 
Tz 2z-0,51 m 
Individual differences of the strips relative to medium referen- 
ce of:the block are as follows 
  
  
  
  
Strips A B € D E F G 
x {in n)41- 0; 83/47 0;50|- 1,14|+.0,82|+ 0,26|+ 0,391 0,09 
y (in m)|- 0,34|+ 0,05|- 0,08[|+ 0, 79|+: 0, 711]- 1,09/+0,09 
7 din mn) |-:0,33|- 0,72|- 0,33]- 0,94|+ 0,66|+ 0,85{+ 0,47 
  
  
  
  
  
  
  
  
It is noticed that reception losses when the aircraft is chan- 
ging of strip are not completely corrected by the manufacturer 
software ; strips are only linked by the photogrammetric block. 
If bias for each strip is eliminated it is obtained standard 
deviations between GPS positions and points of the view for the 
whole block, with the three kinds of GPS data 
  
  
Differential Pseudoranges and phases Pseudoranges 
“x 0,39 m 0,75 m 4,09 m 
Ty 0,41 m 0, 79m 2,60 m 
TZ 0,20 m 1,14 m 4,20 m 
  
  
  
  
  
  
2) As for Amiens test site, GPS measures contribution in ad- 
justment with all control points is negligible.