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The purpose of this paper is to compare the accuracy of shape of an element of the main rotor of a helicopter reconstructed from digital photographs and terrestrial scanner. The purpose of the main rotor is to generate the thrust necessary for the flight (forward, backward, sideward), as well as the moments for stability and control. The construction of such types of objects requires very high precision, since the admissible error of the reproduced part amounts to 0.1 mm. To carry out an analysis of the accuracy, 3D models obtained from different data were generated. A first reference model was created from the design data.. Design data allow to draw profiles of the main rotor and then describe its surface, and it is possible to measure coordinates of any point of the object. A second model was obtained from digital images taken by the Canon EOS 20D camera and with use of two types of coded and uncoded reference points placed on the object. Automatic image matching was executed in the PhotoModeler Scanner software. The third model was reconstructed on the basis of data from terrestrial laser scanning, where the industrial precise ATOS II scanner from the GOM company was used. In addition, special target points for automatic scan matching on this object were located. A comparison of these two generated 3D models with the reference model was carried out in the NX program, which is an advanced CAD/CAM/CAE software. Based on the analysis, both evaluation of the accuracy of the generated models and the time consumption and economic aspects were compared.
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