What is the effect on distances when slope or contamination corrections are applied?

• A. Distances will typically increase when slope or contamination corrections are applied.
• B. Distances will typically decrease when slope or contamination corrections are applied.
• C. Distances are unchanged by slope or contamination.
• D. Only takeoff distance is affected by slope or contamination.

Answer: (A)

Corrections for slope and contamination adjust published runway distances to reflect how real conditions affect performance. An uphill slope slows acceleration and increases the distance needed to reach takeoff speed or to stop on landing. Contaminated surfaces reduce friction, making acceleration slower and braking less effective, so more distance is required to safely take off or land. Because these corrections account for the negative effects, they add distance to the required runway, so distances typically increase when slope or contamination corrections are applied.