  In this work we study the natural focusing of Airy beams symmetric under
reflection of the transverse coordinates. Following a recent proposal, their
angular spectra depend on the absolute value of the third power of the
transverse components of the wave vector. We show that these beams are related
to Airy and Scorer special functions. The caustics have a morphology that does
not correspond to the ones described by standard catastrophe optics. The
structural stability of symmetric Airy beams is experimentally probed
