“…The geometry of the tangent sphere bundles of constant radius r, endowed with the metrics induced by some Riemannian metrics from the ambient tangent bundle, was studied by authors like Abbassi, Boeckx, Calvaruso, Kowalski, Munteanu, Park, Sekigawa, Sekizawa (see [1], [2], [4]- [7], [9], [12]- [14], [16]). In the most part of the papers, such as [4], [5] and [16], the metric considered on the tangent bundle T M was the Sasaki metric, but Boeckx noticed that the unit tangent bundle equipped with the induced Cheeger-Gromoll metric is isometric to the tangent sphere bundle T 1…”