Air-breathing engines (e.g. ramjets) are generally designed for only a very limited operating range. The operating range may be limited by a specific approach velocity or flight altitude. This results in requirements for the geometry and control of the engines. In contrast, control for extended working ranges is relatively costly, complex and can lead to further disadvantages for efficiency. Additional mechanical control of the engine geometry may result in high weight (e.g., due to powerful hydraulics).

In the following, an alternative to mechanical control by means of "volumetric" / fluidic control is presented. In the concept for an adaptive engine geometry (also structural concept), a system according to the invention is registered consisting of a few simple, light and inexpensive components. These components are a "volumetric basic structure," deck structure and, if necessary, composite structure.

The "volumetric base structure" can be formed, for example, of flexible or movable cushions, or chambers (e.g. heavy duty cushions).

The cover structure can be made, for example, of metal or ceramic fibers, or composites. These are efficient and flexible. Mats, nets, fabrics or fleece can be used for this purpose. Layers for thermal insulation or cooling can also be integrated.

To allow for structures that are as flexible as possible, composite structures can be used by means of frictional locking, if necessary.

The objective of the invention is the powerful extension of the working range of thrusters, ideally the conversion of a subsonic ramjet into a ramjet, or a ramjet with an extended working range. This could, for example, enable vertical takeoff for ascent to low Earth orbit using air-breathing thrusters. In addition, there are many possibilities for the design of adaptive structures, e.g., to modify aerodynamic flows on outer contours. Here, stalls can be prevented if necessary or boundary layer flows can be designed in an energy-efficient manner.

Presentation of adaptive engine concept