Method for forming/installing intake duct in waterjet-propelled marine vessel

1. A method of forming/installing an intake duct in a waterjet-propelled marine vessel including a hull molded of composite material, a jet pump and an intake duct having final thickness, comprising:

prefabricating an intake duct upper part having an upper wall and side walls all of less-than-final thickness, and an upper flange portion;

prefabricating a lower part having a lower flange portion;

placing the upper part in the mold; and thereafter

contemporaneously molding the hull and over-molding the prefabricated upper part to form the final-thickness intake duct integral with the hull and including the prefabricated upper part.

2. The method of claim 1 further including placing the lower part adjacent to the upper part such that the flange portions are aligned.

3. The method of claim 2 wherein the placing of the lower part is before the molding step.

4. The method of claim 3 wherein the placing of the lower part adjacent to the upper part includes joining the upper and lower parts.

5. The method of claim 1 wherein the prefabricating of the upper part includes forming the upper part over a mold plug.

6. The method of claim 5 wherein the upper part is formed free of undercuts, thereby enabling unencumbered release of the upper part.

7. The method of claim 1 further including installing a shaft tube in the upper part.

8. The method of claim 1 wherein the prefabricating of the upper part includes adding a shaft tube.

9. The method of claim 8 wherein the shaft tube is integrally formed with the upper part.

10. The method of claim 1 wherein the prefabricating of the upper part includes forming an intake duct mount for installation of an intake grid.