We consider two continuous-time generalizations of conservative random walks
introduced in [J.Englander and S.Volkov (2022)], an orthogonal and a
spherically-symmetrical one; the latter model is known as {\em random flights}.
For both models, we show the transience of the walks when d≥2 and the rate
of changing of direction follows power law t−α, 0<α≤1, or
the law (lnt)−β where β>2