Excitation of Surface guided electromagnetic waves (SGEW) of optical wave range in chiral liquid crystals (CLC) are theoretically examined in the framework of dynamical diffraction theory. In contrast to the traditionally discussed method of SGEW excitation by means of attenuated total external reflection (ATER) the SGEW excitation by a beam incident at a CLC film from the side of a boundary without total internal reflection (TIR) is investigated. In the general case an analytical description of the SEW excitation can not be carried out. It is why the limiting case allowing simplification of the problem, namely, SGEW of the second order diffraction, is examined in details.