The predecessor to the Icarus engine and the original engine designed for the Aether launcher. It used “Rocket Candy” as a propellant, and the grains were in the BATES configuration. It had a glass-fibre engine casing, a new nozzle design—manufactured from pertinax and aluminium—and an igniter system consisting of a commercial ammonium perchlorate grain housed in a 3D printed basket, a pyro-bolt and two squibs.
Several single grain motor and igniter tests were performed successfully, however, a successful full-scale test was never achieved. This was deemed to be the result of casing and propellant grains quality issues and some design flaws due to incorrect simulations.
All these issues have been addressed in the design of the Icarus engine, but were sufficient for the Asimov project to be cancelled.