Anti-icing system and aircraft

1. An anti-icing system that blows heated gas to an inner surface of a wing of an aircraft, the anti-icing system comprising:

a piccolo tube that includes a flow path through which the heated gas flows in a longitudinal direction from a rear end to a front end, and a plurality of ejection holes provided along the longitudinal direction to make the flow path communicate with an outside; and

a supply source that supplies the heated gas toward the piccolo tube, wherein

the piccolo tube is held to cause positions of the respective ejection holes to be fixed in a gravity direction.

2. The anti-icing system according to claim 1 , wherein the piccolo tube has an eccentric structure in which a centroid is deviated downward from a center in a vertical direction.

3. The anti-icing system according to claim 2 , wherein the eccentric structure is configured such that a partial region in a circumferential direction on a cross-sectional surface of the piccolo tube is larger in mass than other regions.

4. The anti-icing system according to claim 3 , wherein the piccolo tube includes a weight on one or both of an inner peripheral surface facing the flow path and an outer peripheral surface, to cause the partial region in the circumferential direction to be larger in mass than the other regions.

5. The anti-icing system according to claim 2 , wherein the eccentric structure is configured such that a partial region in a circumferential direction on a cross-sectional surface of the piccolo tube is larger in a size in a radial direction than other regions.

6. The anti-icing system according to claim 1 , wherein the plurality of ejection holes of the piccolo tube are straightly arranged in a first ejection hole line and a second ejection hole line, the first ejection hole line being disposed on a relatively upper side, and the second ejection hole line being disposed on a lower side of the first ejection hole line.

7. The anti-icing system according to claim 6 , wherein the plurality of ejection holes of the first ejection hole line and the second ejection hole line are alternately arranged in the longitudinal direction on the piccolo tube.

8. The anti-icing system according to claim 2 , wherein the eccentric structure is configured such that a partial region in a circumferential direction on a cross-sectional surface of the piccolo tube is larger in thickness than other regions.

9. The anti-icing system according to claim 2 , wherein the eccentric structure of the piccolo tube is configured such that a partial region in a circumferential direction of the piccolo tube includes a material having density larger than that of other regions.

10. The anti-icing system according to claim 1 , wherein the piccolo tube rotates relative to the main wing.

11. The anti-icing system according to claim 1 , wherein the main wing is provided with a vane, and the vane is coupled with the piccolo tube so as not to rotate relative to each other.

12. An aircraft comprising the anti-icing system according to claim 1 .

13. An anti-icing system that blows heated gas to an inner surface of a wing of an aircraft, the anti-icing system comprising:

a piccolo tube that includes a flow path through which the heated gas flows in a longitudinal direction from a rear end to a front end, and a plurality of ejection holes provided along the longitudinal direction to make the flow path communicate with an outside; and

a supply source that supplies the heated gas toward the piccolo tube, wherein

the plurality of ejection holes of the piccolo tube are straightly arranged in a first ejection hole line and a second ejection hole line, the first ejection hole line being disposed on a relatively upper side, and the second ejection hole line being disposed on a lower side of the first ejection hole line,

the piccolo tube includes a damper that adjusts a flow amount Q 1 of the heated gas ejected from the first ejection hole line, and a flow amount Q 2 of the heated gas ejected from the second ejection hole line, and

the damper increases and decreases the flow amount Q 2 inversely to increase and decrease of the flow amount Q 1 .

14. The anti-icing system according to claim 13 , wherein

the flow path of the piccolo tube is equally partitioned into an upper flow path corresponding to the first ejection hole line and a lower flow path corresponding to the second ejection hole line, and

the damper is a first damper that adjusts an amount of the heated gas flowing into each of the upper flow path and the lower flow path.

15. The anti-icing system according to claim 14 , wherein the first damper is pivotably provided in the piccolo tube.

16. The anti-icing system according to claim 15 , wherein:

the piccolo tube includes a partition that equally partitions the flow path into the upper flow path and the lower flow path; and

the first damper is pivotably provided in the piccolo tube such that a part of the first damper is coincident with the partition.

17. The anti-icing system according to claim 13 , wherein the damper is a second damper that is provided inside the flow path and blocks the plurality of ejection holes configuring the first ejection hole line and the plurality of ejection holes configuring the second ejection hole line.

18. The anti-icing system according to claim 17 , wherein the second damper has a surface in contact with the piccolo tube, the surface having curvature substantially equal to that of an inner peripheral surface of the piccolo tube.

19. The anti-icing system according to claim 17 , wherein the second damper has a width that is larger than an inner diameter of each of the plurality of ejection holes and is smaller than a distance between the first ejection hole line and the second ejection hole line.

20. An aircraft comprising the anti-icing system according to claim 13 .