In this paper, a theoretical approach has been used in order to present the physical characteristics of tachyons with real mass. The procedure of the transfer from the Einstein’s physics into the world of superluminal particles has been given. In addition, the tachyon transformation matrix has been constructed using the principle of correspondence between these two physics. With the usage of the tachyon matrix, it has been shown how length contraction and time dilatation are calculated in the tachyons case. A particular attention has been devoted to measuring the velocity of tachyons and their potential flavor oscillations since it should be kept in mind that there is no rest reference frame attached to tachyon world lines and, in that sense, special relativity does not treat tachyons on the same footing as particles that are slower than light. It has been demonstrated, using the Lorentz transformation matrix, that it is impossible to measure the velocities above the speed of light with the method of measuring time of flight in laboratories over a certain distance. It has been particularly disclosed that tachyons as isolated particles each on its own could not exist in nature, and if they did exist, they would always appear united with other tachyon types. Owing to that tachyon characteristic, obtained by theoretical consideration, it has been concluded that tachyons, rather than neutrinos as subluminal particles, could comply with the definition for the occurrence of the oscillation phenomena between different tachyon types. Furthermore, the analysis of the velocity of emitted neutrinos during the explosion of Supernova SN1987A has been conducted in the spirit of the proposed theory, where it has been demonstrated that it is possible to measure even superluminal velocities with the usage of that measuring method.