A delivery system for an inflatable endoluminal prosthesis, comprising: a delivery catheter comprising an elongate shaft including a proximal section and a fill tube including a fill tube lumen extending axially within the fill tube; an endoluminal prosthesis releasably secured to the proximal section of the delivery catheter, the endoluminal prosthesis including an inflatable portion with an interior volume in fluid communication with a inflation port, and a proximal end of the fill tube of the catheter releasably coupled to the inflation port; and a fill tube retention mechanism that releasably secures the fill tube lumen of the fill tube in fluid communication with the inflation port, comprising: a tab which is disposed at a distal end of the endoluminal prosthesis in substantially fixed relation to the inflation port and which includes an aperture in the tab which is separated from the inflation port by a predetermined distance, a fitting secured to a proximal portion of the fill tube of the delivery catheter which extends laterally from the fill tube, which includes at least a portion that is sized to pass through the aperture in the tab, which is disposed a distance from a proximal end of the fill tube that allows the fill tube to be engaged with the inflation port while the fitting is disposed within the aperture, and which has a passage through the fitting, and a release wire including an outer transverse dimension and axial bending stiffness that allows the release wire to pass through the passage of the fitting and mechanically capture the tab to the fitting with the tab disposed between the release wire and the fill tube and the release wire disposed in the passage, characterized in that the aperture of the tab of the endoluminal prosthesis closely fits an outer transverse surface of the fitting. a delivery catheter comprising an elongate shaft including a proximal section and a fill tube including a fill tube lumen extending axially within the fill tube; an endoluminal prosthesis releasably secured to the proximal section of the delivery catheter, the endoluminal prosthesis including an inflatable portion with an interior volume in fluid communication with a inflation port, and a proximal end of the fill tube of the catheter releasably coupled to the inflation port; and a fill tube retention mechanism that releasably secures the fill tube lumen of the fill tube in fluid communication with the inflation port, comprising: a tab which is disposed at a distal end of the endoluminal prosthesis in substantially fixed relation to the inflation port and which includes an aperture in the tab which is separated from the inflation port by a predetermined distance, a fitting secured to a proximal portion of the fill tube of the delivery catheter which extends laterally from the fill tube, which includes at least a portion that is sized to pass through the aperture in the tab, which is disposed a distance from a proximal end of the fill tube that allows the fill tube to be engaged with the inflation port while the fitting is disposed within the aperture, and which has a passage through the fitting, and a release wire including an outer transverse dimension and axial bending stiffness that allows the release wire to pass through the passage of the fitting and mechanically capture the tab to the fitting with the tab disposed between the release wire and the fill tube and the release wire disposed in the passage, a tab which is disposed at a distal end of the endoluminal prosthesis in substantially fixed relation to the inflation port and which includes an aperture in the tab which is separated from the inflation port by a predetermined distance, a fitting secured to a proximal portion of the fill tube of the delivery catheter which extends laterally from the fill tube, which includes at least a portion that is sized to pass through the aperture in the tab, which is disposed a distance from a proximal end of the fill tube that allows the fill tube to be engaged with the inflation port while the fitting is disposed within the aperture, and which has a passage through the fitting, and a release wire including an outer transverse dimension and axial bending stiffness that allows the release wire to pass through the passage of the fitting and mechanically capture the tab to the fitting with the tab disposed between the release wire and the fill tube and the release wire disposed in the passage,