A suspension system for an aircraft auxiliary power unit located in a fuselage structure, the system comprising: - a plurality of struts extending between the auxiliary power unit and the fuselage structure, - a plurality of auxiliary power unit attachment brackets (51, 52) for connecting the strut to the auxiliary power unit, - a plurality of vibration isolators for joining the struts and the auxiliary power unit attachment bracket (51, 52), the vibration isolators comprising a housing in connection with the struts for enclosing an elastomeric element in the loadpath for damping vibrations, at least one of the vibration isolators comprising a cone-bolt in connection with the housing at one end and attached to the auxiliary power unit attachment brackets (51, 52) at the other end and the cone-bolt being male with respect to the auxiliary power unit attachment brackets (51, 52), characterised in that: - at least one of the auxiliary power unit attachment brackets (51,52) is divided into at least two parts, a first part wrapping at least a first longitudinal portion of the cone-bolt and connected to the auxiliary power unit and a second part wrapping at least a second longitudinal portion of the cone-bolt and connected to the auxiliary power unit, and - at least one of the vibration isolators further comprises: - thecone-bolt having a longitudinal threaded hollow, being said longitudinal hollow open at the end of the auxiliary power unit attachment bracket (51, 52), - an inner bolt partially located within the hollow of the cone-bolt and threaded to the upper part of the cone-bolt, - an outer bolt having a longitudinal through-hole and partially located within the hollow of the cone-bolt and comprising an external thread that engages the thread of the cone-bolt, the inner bolt extending across the hollow of said outer bolt and configured so that the outer bolt is threaded to the bottom part of the cone-bolt and male with respect to the cone-bolt and female with respect to the inner bolt. - a plurality of struts extending between the auxiliary power unit and the fuselage structure, - a plurality of auxiliary power unit attachment brackets (51, 52) for connecting the strut to the auxiliary power unit, - a plurality of vibration isolators for joining the struts and the auxiliary power unit attachment bracket (51, 52), the vibration isolators comprising a housing in connection with the struts for enclosing an elastomeric element in the loadpath for damping vibrations, - at least one of the auxiliary power unit attachment brackets (51,52) is divided into at least two parts, a first part wrapping at least a first longitudinal portion of the cone-bolt and connected to the auxiliary power unit and a second part wrapping at least a second longitudinal portion of the cone-bolt and connected to the auxiliary power unit, and - at least one of the vibration isolators further comprises: - thecone-bolt having a longitudinal threaded hollow, being said longitudinal hollow open at the end of the auxiliary power unit attachment bracket (51, 52), - an inner bolt partially located within the hollow of the cone-bolt and threaded to the upper part of the cone-bolt, - an outer bolt having a longitudinal through-hole and partially located within the hollow of the cone-bolt and comprising an external thread that engages the thread of the cone-bolt, the inner bolt extending across the hollow of said outer bolt and configured so that the outer bolt is threaded to the bottom part of the cone-bolt and male with respect to the cone-bolt and female with respect to the inner bolt. - thecone-bolt having a longitudinal threaded hollow, being said longitudinal hollow open at the end of the auxiliary power unit attachment bracket (51, 52), - an inner bolt partially located within the hollow of the cone-bolt and threaded to the upper part of the cone-bolt, - an outer bolt having a longitudinal through-hole and partially located within the hollow of the cone-bolt and comprising an external thread that engages the thread of the cone-bolt, the inner bolt extending across the hollow of said outer bolt and configured so that the outer bolt is threaded to the bottom part of the cone-bolt and male with respect to the cone-bolt and female with respect to the inner bolt.