Apogee kick motor Apogee kick motor An apogee kick motor (AKM) refers to a rocket motor that is regularly employed on artificial satellites to provide the final impulse to change the trajectory from the transfer orbit into its final (most commonly circular) orbit. For a satellite launched from the Earth, the rocket firing is done at the highest point of the transfer orbit, known as the apogee, thus giving the engine its name. An apogee kick motor is used, for example, for satellites launched into a geostationary orbit. As the vast majority of geostationary satellite launches are carried out from spaceports at a
Liquid apogee engine be prohibited or restricted in the near- to mid-term. Exemptions are being sought to allow to be used for space applications, however to mitigate this risk, companies are investigating alternative propellants and engine designs. A change over to these alternative propellants is not straightforward, and issues such as performance, reliability and compatibility (e.g. satellite propulsion system and launch-site infrastructure) require investigation. The performance of an apogee engine is usually quoted in terms of vacuum specific impulse and vacuum thrust. However, there are many other details which influence performance: A typical 500 N-class hypergolic liquid apogee engine has a vacuum specific