Traverse Closure Error

Also known as misclosure · closure error

Ec=(ΣLat)2+(ΣDep)2E_c = \sqrt{\left(\Sigma\text{Lat}\right)^{2} + \left(\Sigma\text{Dep}\right)^{2}}

Enter your known values, leave one input blank, and solves for the missing one. Try different units for next level excitement!

Learning zone

Walk a closed traverse and you finish where you started, so in a perfect world the latitudes sum to zero and so do the departures. They never do. Whatever is left over is the misclosure, and because the two residuals are perpendicular the total error is their hypotenuse. The direction of that closing line is informative too — a misclosure that lies consistently along one bearing usually means a systematic problem such as an uncalibrated tape or a mis-set instrument height, while a randomly oriented one is ordinary measurement noise.

A worked example: a five-sided boundary traverse closes with ΣLat = +0.24 ft and ΣDep = −0.32 ft. The linear misclosure is √(0.24² + 0.32²) = 0.40 ft — a tidy 3-4-5 triangle. Whether 0.40 ft is acceptable depends entirely on the perimeter, which is why the closure error is almost always quoted as a precision ratio rather than a raw length. Before adjusting anything by the compass rule or least squares, check the angular closure first: an angle blunder shows up as a misclosure that no distance adjustment can absorb.

Traverse Closure Error
Ec=(ΣLat)2+(ΣDep)2E_c = \sqrt{\left(\Sigma\text{Lat}\right)^{2} + \left(\Sigma\text{Dep}\right)^{2}}
Where
  • EcE_c= Linear closure error
  • ΣLat\Sigma\text{Lat}= Sum of the latitudes
  • ΣDep\Sigma\text{Dep}= Sum of the departures
Missing one of these? Work it out first, then come back