Sliding variant adjustable CARET intake duct

The invention relates to a sliding variant adjustable CARET intake duct, wherein the shape of a cross section of the intake duct is a parallelogram, a lip of the intake duct is in a typical dual-beveling shape, and first-grade fixed compression sloping plates are arranged on the upper side wall and inner side wall of an inlet so as to form a CARET wing-shaped wave rider compression surface; a first-grade adjustable compression sloping plate and a first-grade follow-up expansion sloping plate which are composed of parallel sliding mechanisms are arranged at the rear of the fixed compression sloping plate of the upper side wall, the compression sloping plate is connected with the expansion sloping plate through a flexible structure, and pressure equalizing holes are formed in the expansion sloping plate; and boundary layer absorption holes are formed in the fixed compression sloping plates of the intake duct, and a bleed valve is arranged on a side wall. According to the scheme, by virtue of parallel slide of the compression sloping plate in a lowering process, the compression sloping plate does not intervene with the side wall structure of the parallelogram, and no gap exists. When an aircraft flies at a subsonic speed or a low supersonic speed, the adjustable compression sloping plate slides to retract, and the incoming flow is compressed by the fixed compression sloping plates, thereby improving high-Mach-number total pressure recovery. The scheme has the advantages of realizing full-envelope high total pressure recovery and keeping low target characteristics of internal pipelines.