Injection apparatus for a rocket engine

An injection apparatus for a rocket engine, comprising:

• an injection plate delimiting a combustion chamber upstream,
• a plurality of coaxial injection elements distributed in the injection plate, each coaxial injection element forming an inner outlet opening, delimited by a central sleeve body, for a first propellant component and an outer outlet opening for a second propellant component, wherein the outer outlet opening is formed between the central sleeve body and a wall section which surrounds the central sleeve body in an annular manner,
• wherein in a partial number of the coaxial injection elements, the central sleeve body projects from the wall section in a direction towards the combustion chamber,
• wherein the central sleeve body comprises a plurality of tangential holes distributed in a peripheral direction, through which the first propellant component enters the central sleeve body,
• wherein the injection plate is flat on a plate side that faces the combustion chamber, at least in a region of the coaxial injection elements, in which the wall section is flush with the injection plate, and, in the partial number of the coaxial injection elements, the central sleeve body protrudes from the injection plate on the plate side that faces the combustion chamber, and
• wherein in a remaining partial number of the coaxial injection elements, an axial end face of the central sleeve body that faces the combustion chamber is flush with the plate side of the injection plate that faces the combustion chamber, so that the central sleeve body does not protrude relative to the plate side of the injection plate.