CALLISTO vs. standard ELV : what does matter when System is at stake

Abstract

The CALLISTO Vehicle is a flight demonstrator for future reusable launcher stages. The program involves three countries and their space organizations : CNES for France, JAXA for Japan and DLR for Germany. The flights will be conducted from the CSG, Europe's Spaceport for commercial launches in French Guiana. One challenge is to develop the skills of all three partners during the course of the project. This knowhow includes products and Vehicle design, ground segment set-up and post-flight operations for Vehicle recovery and reuse. This paper details some differences in between CALLISTO and a standard mid- or heavy-sized ELV focusing to system queries, especially: - size (CALLISTO much smaller than a standard mid- or heavy ELV class), - "recover" features : mechanical engineering, aero-based flight control during descent, additional transient phases (especially touchdown), GNC & relevant accuracy for landing target, - "reuse" features : post-landing phase operations and Maintenance & Repair Operations, - a demonstrator vs. an operational Launcher and its so-called Payload. No hard data or figures with numbers are provided. The motivation is rather detailing somehow contradicting design (or operations) trends and derived solutions that makes CALLISTO what it is : in short, the essence of system engineering. Last, but not the least, the content of the paper benefits from maturity of the Project with some products being "ready for flight" status and others leaving the drawing board.