Which of the following is a common hazard associated with air tankers?

Limited visibility is a common hazard associated with air tankers, especially when they are flying in areas impacted by wildfires. Smoke, ash, and changing weather conditions can significantly reduce visibility, making it challenging for pilots to navigate and execute drops accurately. This poses risks not only to the effectiveness of the firefighting effort but also to the safety of the aircrew and surrounding environments.

High-altitude flying, while it does present challenges, is not typically the primary concern for air tankers, which usually operate at lower altitudes to effectively deliver fire retardant. Excessive fuel consumption is a factor in operational costs, but it's not categorized as a direct hazard to safety in the same manner as visibility issues. Frequent mechanical failures could be a concern; however, air tankers are required to undergo stringent maintenance checks and are designed for reliability during operations, making this less of a common hazard compared to visibility challenges caused by fire conditions.