THE ROLE OF AERIAL SURVEYS IN HIGHWAY ENGINEERING 
William T. Pryor, Chief 
Aerial Surveys Branch 
Highway Standards Division 
Bureau of Public Roads 
U. S. Department of Commerce 
Washington, D. C. 
Prepared for 
Ninth Congress 
International Society for Photogrammetry 
London, England 
September 5-17, 1960 
  
  
  
  
  
  
  
CONTENTS 
Abstract . + ... + tou ma 9 ee ee + 0e ee es s. lii 
Introduction . . M sx au Eis ea yey a ae, 1 
Early development "3 ^. 5. Re bay heh ow vee Te 2 
Highway service standards... +. + + + +. . . . . 0 ew ly 
Highway location in retrospect . . . . +." . eu... so s 4 
The hiehway teai :.… « « =…-+- 0.00 0e. mu. es ee nee» 6 
Aspects and arrangement . .. + «e + « utat totae o» + = 6 
Nature of aerial photographs and aerial surveys for highways . . . . 8 
Aerial photographs ... cv + e + eu sn tice. TY pn 8 
Aerial surveys . . . Sai. eae cae. 10 
Applications of aerial Surveys in pigway engineering "uae X e we um 5 11 
Applications in highway planning . . . #4 04e Ce 0 11 
Applications in reconnaissance survey of area . . . . . . . +. + 13 
Photographic coverage “sie oe es Lam 18 a S m 13 
Procedures » . .« + .» o ie J^ ^ 6e +4, 0e + + ^ 13 
Stereograms illustrating route toca ions ee 2 ee … ee, Us 15 
Applications in reconnaissance survey of alternate routes a …. eo. +. + 20 
Photographic coverage e... "uS "RE SR uS ue tuus aa t, on 20 
Procedures . . eue comin Wie Tw t. s 20 
Noneritical topography and land use + e ir. Te a 20 
Critical topography and land use ee ee . 0 + + +» = 21 
Clearing before preliminary survey . + + + + . oo . . . 22 
When large scale photographs are used . . . . 22 
Applications in preliminary survey and design of highway on à approved 
route 4 o. . 23 
Direct procedure in preliminary survey and design o QM uw 23 
Photographic targets . . . . A ES BD 
Route photography J ood ad Eid gy 4 4 d d c (8 27 
Horizontal ‘and vertical control . EN «^. 27 
Plane coordinates e 74 . (MX 27 
Topographic maps compiled by atereophatogéemetrtie "methods UN: 28 
Types of photogrammetric instruments used N v. 31. 
Accuracy and completeness tests of maps . . . . . . . . 32 
Correction, revision, and completion of maps  . |. . 4. 34 
Engineering use of photographs and topographic maps "  . i. © 35