- 30 - 
Florida ; " Photogrammetric Engineering ", March, 196 2 [8]. This new system is aimed to im 
prove the efficiency of world-wide photo mapping missions by using Jet Boeing RC-135 airpla 
nes, improved automatic navigation means for forward and sidelap control, improved accuracy 
for positioning of exposure stations by replacing the presently used Hiran system by a more 
accurate Shiran system, by accurate recording of tilt components for the direct airborne deter 
mination of ground control and thus eliminating tedious and inconsistent ground surveying. 
U. S. Naval Oceanographic Office 
This agency does not use aerial triangulation with auxiliary data. 
The Department of Geodetic Science, The Ohio State University 
A block triangulation (Massif Central ) was performed for the " Group of Study for Ex 
perimental Researches on Blocks of Strips ", International Society of Photogrammetry, consis 
ting of three principal strips and eight longitudinal strips and using statoscope data. This block 
triangulation covers an area of 80 x 80 km^. The ground elevations in the block vary, between 
300 m and 1 600 m above sea level, and the average ground elevation amounts to 800 m above 
sea level. Vertical photography, from appr. 9 000 m above sea level, was taken with the Wild 
RC 7 Plate Camera (nominal focal length f = 100 mm, photograph format 140 x 140 mm) and sta 
toscope data. With an overlap of 70 % and a sidelap between adjacent longitudinal strips of 15 % 
and a photo scale of 1 : 80, 000, an average number per principal strip of 28 models and of 25 
models per longitudinal strip, i. e. 280 models, were triangulated according to the aeroleveling 
procedure described in " The Practice of Spatial Aerial Triangulation " by A. J. Brandenber- 
ger, Photogrammetric Institute, Federal Institute of Technology, Zurich, 1951 [2]. To check 
the accuracy attained by the block triangulation, appr. 300 test points were given. The block 
adjustment was performed according to[2] using in each principal strip a group of given points 
at both ends and in the middle of the strip. The following standard residual, errors were obtai 
ned : M^. = + 6.5 m, M^ = 16.9 m, M = 1 9. 0 m. For comparison purposes these standard 
errors have to be reduced to standara errors to be expected when using a standard wide angle 
camera 9 x 9", f = 6" to yield the following standard errors : M = 1 4. 3 m, M^ = 1 4. 6 m, 
M^ = ^6.0 m. This accuracy is sufficient to provide ground control for mapping in the scale 
1 : 50, 000 with a contour interval of 20 m if a standard wide angle camera is used. The perfor 
mance of this block triangulation required a total time of 813 man hours (instrumental work plus 
adjustment) or 2 hours 55 minutes per model. The various phases of this test were carried out 
by Dr. F. J. Montero, Mr. R. B. Forrest, and Mr. R. K. H. Adler. - Also, a super long strip 
triangulation (Phoenix, Arizona, to Los Angeles, California : 9 x 9"/6" vertical Metrogon pho 
tography ; 60 % overlap ; flight height 12 km above ground ; length of the strip 650 km ; 80 mo - 
dels ; area of strip nearly 12, 000 km^ ; triangulated at the Wild Autograph A7 ; see " Aerial 
Triangulation with Auxiliary Data " by A. J. Brandenberger, " Photogrammetria ", 1960) was 
adjusted. Although no auxiliary data were available this strip was triangulated according to the 
principle of aeroleveling (bz = 0 method). A horizontal adjustment with groups of given ground 
control points at X = 0, X = 270 km, X = 390 km, X = 500 km, X = 610 km, and IV. order poly 
nomials was performed using semi-graphical procedures. This adjustment was tested with 120 
test points and the following standard horizontal error was obtained : Mp =\/ M^ + M^ = 15.9m. 
It is considered that this accuracy is sufficient to provide horizontal ground control for mapping 
in scales 1:50, 000 and smaller. This strip triangulation required one man hour instrumental 
time per model and appr. 11/4 man hour per model for the adjustment. The vertical adjust 
ment of the strip using different procedures is still in process and it is anticipated to report on 
this phase at a later date. The strip was also adjusted by using only two independent base lines 
and azimuths (no absolute control) at both ends of the strip and an average horizontal closure 
error AS = y(X)^ + ( Y)^ of appr. 100 m or appr. 3" in terms of geographic coordinates was 
found. The various phases of this test were carried out by Dr. A. J. Brandenberger, Dr.G.Mu- 
lert, Mr. K. Bretterbauer, Mr. R. B. Forrest, Mr. S. Ghosh, Mr. A. Soliman and Mr. S.Weis- 
sman. - Considerable research was done in connection with the new U. S. Air Force develop 
ment program to design an " Integrated Photogrammetric Mapping System " (USQ 28) for world 
wide photo mapping missions. Reference is made to : " Photogrammetric Mapping Using Verti- 
cality Data " by A. J. Brandenberger, Final Report, OSU RF project 1432 to Headquarters 1360