What is the wing movement of a penguin speed?

The wing movement of a penguin is not measured in terms of speed, as penguins do not fly. Instead, penguins use their wings for swimming and steering in the water. The wing flapping motion of a penguin can reach frequencies of up to 2-3 flaps per second during fast swimming. Their powerful wingstrokes, combined with their streamlined bodies, allow them to reach speeds of up to 20 kilometers per hour (12.4 miles per hour) underwater.