ALSET - Japanese Air Launch System Ground Tests and Applications

The Air Launch System Enabling Technology (ALSET) project is a Japanese Ministry of Economy, Trade and Industry (METI) funded project whose purpose is to study air launch orbital payload delivery systems and related technologies. The project is a first step toward an operational commercial air launch system that will use a multistage solid rocket to deliver small payloads on the order of 100 to 200 kilograms into Low Earth Orbit (LEO). An air drop type launch approach to space transportation provides high reliability, flexibility, and responsiveness to meet the future needs of small satellite operators. ALSET culminates in a series of drop tests of an inert launch vehicle (a mass simulator) to demonstrate the technologies necessary for the operational system. The baseline system design uses a carriage extraction system method whereby the rocket is extracted from a C-130 aircraft on a TYPE-V platform. Two 28-foot extraction parachutes are used to pull the platform from the aircraft. Three 100-foot cargo parachutes are then deployed for deceleration prior to release of the rocket from the platform for launch. The baseline test site selected for the drop test is the Yuma Test Center (YTC) in Arizona, USA. The large drop zones available at the YTC are ideal for ALSET testing. Additionally, the YTC’s considerable experience with similar test activities, including the NASA Ares Jumbo Drop Test Vehicle drop tests, minimizes technical risks. The authors’ efforts to date completed the Critical Design Review (CDR) for the ALSET Drop Test in February and March 2015. The ALSET program is now ready for manufacturing for the ALSET Drop Test. As the prospective applications of ALSET to C4ISR missions, two case studies were conducted. The studies demonstrated the effectiveness of the air launch system. The responsiveness and flexibility of the air launch system enables small satellites to collect the ground information desired in short time, and to observe the target highfrequently by sequential satellite launches and forming a constellation.