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Running Fix - Two Observations

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Estimate running-fix error at second observation from interval, own speed, and advance-method correction - sensitivity of the fix to course/speed change.

Formula

$$ \epsilon = \sqrt{(D \sin \epsilon_C)^2 + (D \epsilon_S)^2} $$

Symbol legend

SymbolMeaningUnitSource
$D$DR distance runnmspeed × time
$\epsilon_C$Course errordeggyro/compass
$\epsilon_S$Speed error%log precision

Sources

  • Bowditch Pub.9 Ch.23.