Pacing and Distance
Distance from pace count with terrain correction; reference table per stride length.
Example
You enter
- Calibration distance (ft) 100
- Calibration paces 38
- Current paces 120
- Terrain flat
You get
- Pace length 2.63 ft
- Distance (ft) 315.79
- Distance m 96.25
- Terrain factor 1
Checked against published worked examples from: National Wildfire Coordinating Group (NWCG); Alabama Cooperative Extension System.
Details, formula, and sources
Formula or tableDistance = pace_count × calibrated pace length ÷ terrain factor, the factor being how many more paces rough ground takes per unit distance: flat 1.00 / rolling 1.10 / steep 1.25 / brush 1.30 / snow 1.40.
Source and editionU.S. Army FM 3-25.26 (Map Reading and Land Navigation) and FM 21-26 (predecessor) by name.
Free accessU.S. Army field manuals free at army.mil and at archive.org.
What governsGeometry is not forecasting. Avalanche advisory and incident commander govern.
API field namescalibration_distance_ft, calibration_paces, current_paces, terrain, pace_length_ft, distance_ft, distance_m, terrain_factor
- Terrain factors divide by flat 1.00 / rolling 1.10 / steep 1.25 / brush 1.30 / snow 1.40; a planning convention -- FM 3-25.26 names slope, vegetation, snow and fatigue as shortening the pace but gives no factors, so calibrate on the ground you will walkproject convention