What is the formula to convert feet per nautical mile to a climb gradient percent?

• A. Run/Rise x 100
• B. Rise/Run x 100
• C. Rise x Run
• D. (Rise/Run) with no 100 factor

Answer: (B)

Climb gradient percent is just a way of expressing how steep a climb is by comparing vertical gain to horizontal distance. To convert a rise over a run into a percent, you take the vertical change (rise) and divide it by the horizontal distance (run), then multiply by 100. That gives rise over run as a dimensionless ratio in percent.

When you have feet per nautical mile, make sure the run is in a consistent unit with the rise. Convert the nautical miles to feet (1 NM ≈ 6076 ft) or convert both to a common unit, then apply Rise/Run × 100. That’s why Rise/Run × 100 is the correct form for a climb gradient percent.

The reciprocal (Run/Rise) would give the inverse slope, not the climb gradient. Dropping the 100 factor would yield a decimal fraction rather than a percentage.