A rough overview of the important aspects and problem areas associated with the development of Integral Rocket Ramjet (IRR) technology is given in this report. The IRR is a supersonic air-breathing concept in which the gas generator produces fuel-rich gases. These fuel-rich gases are burnt in the secondary combustion chamber with ambient air captured and decelerated in the inlet. During the boost phase, a solid propellant booster provides the thrust necessary to achieve the velocity at which the ramjet may be operated (about M = 2). The booster is integrated in the secondary combustion chamber.

The patent application relates to the design of a ramjet engine whereby air injection ports and fuel injection systems are arranged in a manner to enhance flame stability.

This report describes the main accomplishments of a collaborative Canadian-Dutch project known as the Integral Rocket Ramjet Demonstration Program (IRRDP) to investigate the key technologies of air-breathing missile propulsion through the design, fabrication, & testing of a solid fuel ducted rocket engine with an integral booster for a medium-range air-launched missile. It begins by discussing the requirements for an integral rocket ramjet engine, then reviews activities related to the development of a missile design tool & performance prediction tool, computational fluid dynamics evaluation of the intake & port covers, development of a new solid propellant for a gas generator used in ducted rocket propulsion, modelling of the ramjet combustor in a water tunnel, combustion tests, modelling & propellant development for the nozzle-less booster, and the final design.