Abstract
As the vertical parallaxes are observed by the analytical aerotirangulation only at the beginning and are used to the end of computation without repeating the observation usually, the gross errors can hardly be found in halfway if exist. To improve this circumstance the closing conditions of the pass points are introduced to check, find and if necessary reject the gross errors in halfway.
Further it is suggested to explain the prompt error accumlation in the aerial triangulation by the well known Random Walking Theory instead of the Double Summation Theory from the theoretical consideration and experimental simulation with long numerical sequence.
