This study investigates the oscillating behavior of a heavy pendulum in a vertical air jet. The behavior of a pendulum, initially inclined at a certain angle, is investigated under the influence of a jet with two distinct Reynolds numbers. A consistent observation is that with the increase in air jet Reynolds number (Re), the time taken by the pendulum to reach its vertical equilibrium state reduces. The air jet’s flow pattern, when deflected by the pendulum, creates a suction pressure that helps the pendulum return to its original position against the force of gravity. As the jet Reynolds number increases, the suction pressure becomes more pronounced, aiding the pendulum’s return to equilibrium. The subsequent effect is an increase in the frictional damping force experienced by the pendulum at its pivot, contributing to the observed behavior. A theoretical model is developed, and numerical results are obtained to support and validate the conclusion that the interplay between the suction pressure and frictional damping force is responsible for the observed reduction in the time taken to reach the vertical equilibrium state with the rise in air jet Re.