A new synthetic strategy for the preparation of macroscopically oriented smectic main chain liquid crystal elastomers (MC-LCE) by the photocrosslinking of laterally functionalized polyesters is presented. X-ray measurements proved the formation of the monodomain and allowed a quantitative determination of the order parameter. The thermo-actuation of our material at the phase transition from the liquid-crystalline to the isotropic phase was demonstrated by temperature dependent measurements of the sample length, showing a fully reversible shape change of approximate to 40%. Mechanical measurements showed that the sample can be stretched by up to 60% along the smectic layer normal without any reorientation of the structure, in contrast to earlier experiments and theoretical predictions. The results are discussed in the context of limited smectic layer correlation in different types of smectic materials.