-6- 
the whole work# 
The plane used was a D, C,3, equipped with a dill EC.8 
camera - 9" x 9"> f=6", Aviogon lenses - and a crew of 3s Pilot, 
Co-Pilot - Photographic Navigator and Camera Operator« 
Although a longer focal length camera, viz., an 
Aviotar cone, should have been used, there was no option in this 
case, since all existing cameras in Mozambique are of the wide 
angle type. 
Fortunately tho whole area is rather flat and free of 
undulation, with the exception of a very small corner in the up 
stream side, which includes part of the Lupata Gorge. 
The following table will illustrate the type of 
terrainj- 
Heights in 
Area distribution in 
Maximum relief 
displacement to be 
meters 
a.m.s,1. 
Acres 
Percentage 
* 
expected at l/lO, 000 
o 
i 
ro 
o 
760.451 ■ 
51.8 
0,3 rams 
o 
1 
° j 
C\J 
202.705 
13.8 
0.4 
o 
1 
o 
121.836 
8.3 
0.4 
60 - 80 
115o969 
7.9 
0.4 " 
80 - 1.00 
146.877 
10.0 
0.7 " 
100 - 170 
118.862 
8.1 
2.0 " 
0 
i 
M 
—0 
0 
1.466,700 
100.0 
—- r — a 
The edge of the area between 100 and 170 meters over 
laps the existing map of l/lO.OOO. In order to reduce tne relief 
displacement to a minimum, the strips were flown with 70fo long and 
30fo side overlap, on average. One of the strips was even flown witn 
80$ long overlap. 
This brought the maximum error in the rectification due 
to relief displacement, down to: 
& \=0.7 x A h m 
The last column of the above table represents therefore, 
the maximum value of relief displacement for the different zones, as 
suming the most unfavourable conditions, i.e., that tne largest height 
differences appear on the corners of the central rectangle to oe rec 
tified.