Abstract: A telescoping propeller shaft includes an elongated hollow cylindrical body having a splined interior surface, the splines defining a minor diameter (x) and a major diameter (y), and a correspondingly splined shaft mating in register with the cylindrical body along an engagement length (L). Major (c) and minor (b) diameters of the splined shaft are less than the respective major (y) and minor (x) diameters of the interior splines of the cylindrical body such that the two shafts can freely telescope at least along the engagement length (L) and a free plunge region (D1). In response to a sufficient inward axial load, the cylindrical body is adapted to telescope over the splined shaft through an interference region (D2) comprising an interference mechanism for energy dissipation.