STRIP::2 
Tx mu" «s, d, Ui “x = 0,30 m 
Ty = 1,44 m we = 0,48 m 
TZ = 3,061 m Yz = 0,23 m 
Strip 3 
Tx = 0,49 m x = 0,20 M 
Ty = 0,95, m vw. 0,421. in 
Tz = 2,64 m Fz = 0,28 m 
It is noticed that standard deviations are about of the same 
order than aerotriangulation residuals. But perhaps better. ac- 
curacies would be possible with better control points. 
b) Introduction of GPS measurements in aerotriangulation. 
If GPS measurements are introduced in aerotriangulation compu- 
tation. with. all. the, control points, there, is. no, significant 
effect. 
c) It is interesting to reduce the number of control points. If 
we keep only 4 points known in x y z at the angles of the block 
the results are as follows, on the check points, for the whole 
block: 
TX 0,22 m 
TY 0,53 m 
«2 - 0,70 m 
This result can appreciably vary according to the choice of the 
four kept control points. 
d) If we continue this trial, we can keep only one point at the 
center of the block. The results on the same check points as 
previously are as follows : 
mx -=0,51->m 
S y 0752 m 
72 = 1 55m 
It is noticed that results remain acceptable for planimetry but 
are degraded in altimetry. The main cause is a lack of trans- 
versal stiffness of the block. For this reason two North-South 
Strips have been added to flight configuration of 1987, in or- 
der to obtain a better transmission of altimetric constants. 
Bl Lunel.test.site 
  
For this sheet computations have been conducted using the three 
kinds of available GPS data : 
- pseudoranges smoothed by phase, with trajectographic correc- 
tion by differential processing, using Creil or Nantes GPS 
records. 
- pseudoranges smoothed by phase, without differential proces- 
sing 
- only pseudoranges 
Aerial triangulation of this mission has been calculated using