Support system for auxiliary power unit
Support system suitable for sustaining an auxiliary power unit of an aircraft to a fixed structure ( 2 ) belonging to a compartment of the auxiliary power unit ( 6 ) of the aircraft. The support system is made in a high mechanical strength material and with high resistance to ignition, and comprises three fittings ( 3, 4, 5 ) two of which are frusto-conical and one with a substantially cylindrical. Fittings ( 3, 4, 5 ) being able to be hollow and being able to comprise an array of lateral ribs. Each one of them presenting a first end ( 7 ) comprising means of attachment of the support system ( 8 ) to the fixed structure ( 2 ) and a second end ( 9 ) comprising means of securing of the support system ( 8 ) which are joined to the auxiliary power unit ( 1 ) in the periphery of the extension of said auxiliary power unit ( 1 ).
1. An auxiliary power unit support system which sustains an auxiliary power unit of an aircraft to a fixed structure belonging to an auxiliary power unit compartment of said aircraft, made in a high mechanical strength material, and with high resistance to ignition, which comprises means of attachment of the support system that are complementary to means of attachment of the fixed structure provided in said fixed structure, and means of securing of the support system that are complementary to means of securing of the auxiliary power unit provided in said auxiliary power unit, wherein the auxiliary power unit support system further comprises at least three fittings, two of which are frusto-conical and one is substantially cylindrical, each of the said fittings comprising a first end and a second end, with said means of attachment of the support system being provided in the said first end and said means of securing of the support system being provided in the said second end; being said first end attached to the fixed structure belonging to said auxiliary power unit compartment and being said second end joined to the auxiliary power unit.
2. The auxiliary power unit support system of claim 1 , wherein said fittings are hollow.
3. The auxiliary power unit support system of claim 1 wherein the fixed structure to which the first end of each of the fittings is attached is located on an upper surface of the auxiliary power unit compartment, and said second end of each of the fittings is joined to said upper surface of the auxiliary power unit in such a way that said auxiliary power unit hangs from those fittings.
4. The auxiliary power unit support system of claim 1 , wherein the fixed structure to which the first end of each of the fittings is attached is located on a lower surface of the auxiliary power unit compartment, and said second end of each of the fittings is joined to said lower surface of the auxiliary power unit; being said auxiliary power unit rested on said fittings.
5. The auxiliary power unit support system of claim 1 , wherein the second ends of each of the fittings are joined to the auxiliary power unit in a zone close to a periphery of an extension of said auxiliary power unit and at least one of said fittings is not located in the straight line defined by the rest of the said fittings.
6. The auxiliary power unit support system of claim 1 , wherein said fittings comprise at least one rear fitting in such a way that said rear fitting is joined to a rear part of the auxiliary power unit, and at least a first forward fitting and a second forward fitting in such a way that said first forward fitting and second forward fitting are joined to a forward part of said auxiliary power unit.
7. The auxiliary power unit support system of claim 6 , wherein said first forward fitting and second forward fitting present a curvature in such a way that the means of securing of the support system of the second end of each of said forward fittings are joined to the auxiliary power unit in a horizontal plane.
8. The auxiliary power unit support system of claim 1 , wherein said means of attachment of the support system which attach said fittings to the fixed structure comprise at least three bolt-holes and at least three bolts complementary to said bolt-holes and in turn complementary to at least another three bolt-holes located in the means of attachment of the fixed structure in the fixed structure.
9. The auxiliary power unit support system of claim 1 , wherein said means of securing of the support system which join said fittings to the auxiliary power unit comprise at least three bolt-holes and at least three bolts complementary to said bolt-holes and in turn complementary to at least another three bolt-holes located in the means of securing of the auxiliary power unit in the auxiliary power unit.
10. The auxiliary power unit support system of claim 6 , wherein the rear fitting presents an array of lateral ribs along the entire length of its outer surface.
11. The auxiliary power unit support system of claim 1 , wherein the high resistance material with which the said support system is produced is PH13-8Mo steel (1.4534).
12. The auxiliary power unit support system of claim 1 , wherein each of the fittings includes an adapter for bars such that said support system for auxiliary power unit is compatible with auxiliary power unit attachment systems using bars.