Steering and backing systems for waterjet craft with underwater discharge

Abstract

The inventive apparatus exercises control of the water flow which is discharged from a marine waterjet propulsor. Typical inventive embodiments comprise plural horizontal and plural vertical blade-like structures which together describe an open-ended, box-like rectilinear configuration characterized by at least two adjacent channels. Every vertical blade-like structure includes, at its aft end, a “steering” flap which is pivotable about a vertical axis. Some inventive embodiments advance marine craft reversing by implementing one or more bucket-like devices behind the inventive apparatus. According to many inventive embodiments, every vertical blade-like structure (other than the two laterally extreme vertical blade-like structures) has a steering flap attributed with lengthwise severability (as if severed by a vertical plane) into two sub-flaps, each sub-flap itself being pivotable about the same vertical axis; in cooperation therewith, the marine craft is reversed by implementing plural “backing” flaps (included in the bottom-side horizontal blade-like structure or structures) which are each pivotable about a horizontal axis. The inventively coordinated movements and dispositions of the flaps, sub-flaps and/or bucket-like devices effect steerable and/or reversible maneuverability of the marine craft. Utilization of the present invention is especially efficacious in the context of waterjet propulsion systems wherein the water flow is discharged underwater; underwater-discharge marine waterjet propulsion, practically unknown but theoretically recognized for its potential benefits, is rendered a real and viable option by the present invention.