WeatherQuestion 80 of 100
On a cold morning you find a thin coat of frost on your aircraft's arms and propeller blades. What is the correct action?
a.Polish the frost smooth so that airflow stays attached to the blades
b.Launch as planned, since frost is harmless at the low speeds a UAS flies
c.Hover briefly at low power and let the rotor wash blow the frost away
d.Remove all frost before flight, since it disrupts airflow and adds weight
Explanation
Frost roughens the surfaces that generate lift, disrupting smooth airflow over the propeller blades and airframe while also adding weight, which reduces thrust and can prevent a normal takeoff. The only acceptable action is to remove all of it before flight. Polishing frost smooth is specifically not acceptable, low airspeed does not make contamination harmless, and attempting to hover it off means the aircraft is already flying in a degraded condition.
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