A large deformation of the tube body resulting from a sight increase of an existing load under which the tube had previously exhibited little, if any, deformation before the load was increased. In unsupported tube lengths, the deflection of the lateral axis of the tube body can rapidly become large, resulting in catastrophic failure. In bounded environments where the tube is concentric to tubing or casing, the buckling can take a sinusoidal or helical form, depending upon the applied load and ratio of tubing (or casing) ID and concentric tube OD.