If a helicopter has landed on a slope, from which side should you never approach?

Approaching a helicopter that has landed on a slope should always be done with caution, as the helicopter's position on the slope creates additional hazards. The correct answer, approaching from the uphill side, is the safest course of action because helicopters are designed to handle their rotor downwash better when being approached from below.

When approaching from the uphill side, you avoid potential hazards associated with the rotor blades, including the risk of being caught in the rotor wash that can be unstable and turbulent. Additionally, approaching a helicopter from the downhill side could lead to the threat of rolling or sliding towards the helicopter, especially if the ground is unstable or loose, which has the potential to result in injury.

Choosing sides based solely on left or right is insufficient without considering the slope's impact on safety. Therefore, while approaching from either side might seem logical in some circumstances, the uphill option clearly indicates the least risk of danger in the context of a landing on a slope, reinforcing the need to always assess the terrain and conditions present when working in proximity to helicopters.