are preferably uni ball connectors and this configuration allows for relative axial movement between engine 117 and secondary duct 105 but this does not allow for vertical or lateral movement the single degree of freedom associated with drag link 109 allows engine movement to push or pull secondary exhaust duct 105 consistently with primary duct 103 and keeps the system in the desired alignment secondary exhaust duct 105 has a curved portion 123 for altering the direction of exhaust flow from its original flow path along central axis 124 of a fixed portion 125 of duct 105 to a direction off the central axis of fixed portion 125 in the nominal orientation cured portion directs flow in the direction shown relative to fixed portion 125 however curved portion 123 is rotatable generally about axis 124 through a range of motion of about 90 degrees to either side or to the extent of the range of motion available in the particular application fig4 shows an end view of secondary duct 105 with curved portion 123 in the nominal position solid lines and rotated to one side broken lines to enable rotation while retaining the function of the means for keeping ducts 103 and 105 concentric a bearing band 127 is disposed between curved portion 123 and struts 113 115 a joint 129 which is shown in fig5 joins curved portion 123 and fixed portion 125 together joint 129 is configured to retain curved portion 123 axially by a retainer 131 while allowing curved portion 123 to rotate relative to fixed portion 125 along central axis 124 also a self lubricated bearing coating 133 preferably rexton is disposed at the interface of curved portion 123 and fixed portion 125 fig6 is an end.