Introduction 
A Commission III Working Group report on analytical adjustment of a block 
of simulated aerial photographs was presented at the 1968 Congress of the 
International Society of Photogrammetry in Lausanne. A broad spectrum of block 
sizes and test cases were studied in that report and many interesting conclu- 
sions drawn from the results. However, the diversity of block dimensions, 
control arrays, and experiments in that set of test prevented meaningful com- 
parison of the various methods. Consequently, one of the charges to Commis- 
sion III, at the eleventh Congress, was to continue investigations of analyti- 
cal block adjustment using simulated photography. 
In September 1970, James M. Anderson of the University of California in 
Berkeley and Everett H. Ramey of the National Ocean Survey were appointed co- 
chairmen of a Commission III Working Group formed to pursue these investigations. 
Suggestions were solicited (via a questionnaire) from potential participants 
with respect to: (a) test block dimensions; (b) desired sidelap and overlap; 
(c) points/photographs; (d) control point configurations; and (e) desired 
flight arrangements. On the basis of responses to these questionnaires, guide- 
lines were established for tests with a uniform block size and specified control 
arrays. 
The general objectives of the study were to: 1) evaluate and compare 
different methods of analytical aerotriangulation and adjustment of blocks using 
uniform block size and control configurations; 2) evaluate and compare several 
ground control configurations; and 3) assess effects of residual systematic 
perturbations remaining in observed plate coordinates after coordinate refine- 
ment. : 
As ultimately formed, the Working Group included the following organiza- 
tions and principal investigators: 
National Research Council of Canada - Ottawa, Canada 
Mr.36. H. Schut. 
Institute Für Angewandte Geodäsie,‘ Frankfurt, 
Prof. Dr. R. Forstner and Universität Stuttgart 
Prof. Dr. Ing. F. Ackermann. 
University of Wisconsin, Madison, Wisconsin, U.S.A. 
Dr. Paul R. Wolf and Mr. Steven Johnson. 
Pacific Aero Survey Co., Ltd., Tokyo, Japan 
Mr. Hiroshi Morito, Mr. Hitoshi Tamura. 
Asia Air Survey, Tokyo, Japan. 
Kokusai Aerial Survey Co., Ltd., Tokyo, Japan 
Mr. Isamu Yamamoto. 
Toyo Aero Survey Co., Ltd., Tokyo, Japan 
Mr. Sohachi Kurihara. 
Helsinki University of Technology, Otaniemi, Finland 
Professor R. S. Halonen. 
United States Army Topographic Command, Washinton, D.C., U.S.A. 
Mr. Richard L. Penrod. 
D.B.A. Systems, Inc., Melbourne, Florida, U.S.A. 
Mr. John À. Strahle.