For a third-order, class I and II geodetic control network, minimum triangulation station spacing is at least?

• A. 0.50 km
• B. 15.00 km
• C. 10.00 km
• D. 5.00 km

Answer: (A)

In a triangulation network, the length of each side (the spacing between stations) controls how angular measurement errors translate into position errors once the network is adjusted. For a third-order network of class I and II, the goal is to keep lines short enough that a small angular error does not blow up into large coordinate errors, while still being practical to observe and compute. A spacing of about 0.5 km keeps the network dense enough to provide strong redundancy and reliable closures, given the typical precision of angle measurements in classic triangulation. If the spacing were much larger, the same angular uncertainty would produce bigger misclosures and poorer network integrity; hence 0.5 km is the minimum that meets the required accuracy and redundancy for this order and class. The other options imply substantially longer spacings, which would compromise the network’s robustness and are not suitable for a third-order, class I/II design.