Loading & PerformanceQuestion 86 of 100
You are launching a fully loaded multirotor from a mountain meadow at 7,500 ft MSL on a hot afternoon. How does the high density altitude affect performance?
a.Thrust increases because the thinner air produces less drag on the propellers
b.Performance is unaffected because electric motors do not need air to burn fuel
c.The propellers produce less thrust, so climbs are slower and endurance is reduced
d.Battery voltage rises with altitude, which offsets any loss of propeller efficiency
Explanation
Propellers generate lift from the air they move, so thin, hot air yields less thrust for the same motor RPM. The aircraft must draw more current to hover, which slows climbs and cuts flight time, and a heavy payload makes this worse. Electric motors do not need air for combustion, but their propellers absolutely do, and altitude does not raise battery voltage.
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