Spaceflight Secondary Payload System (SSPS) and SHERPA Tug - A New Business Model for Secondary and Hosted Payloads

Since the termination of the Falcon 1 program, the opportunities for access to space for small spacecraft have been limited. Spaceflight, Inc. (Spaceflight) is addressing this market need by providing commercial launch services for secondary and hosted payloads by using its Spaceflight Secondary Payload System (SSPS) and SHERPA in-space tug. The SSPS is a system designed to transport up to 1,500 kg of secondary and hosted payloads to space using the excess capacity on Medium and Intermediate class commercial launch vehicles. The SSPS can accommodate up to five 300 kg spacecraft, or many smaller spacecraft, on each of its five ports and operates independently from the primary launch vehicle to simplify payload and mission integration. SHERPA is an in-space tug that builds upon the capabilities of the SSPS by incorporating propulsion and power generation subsystems, which creates a free-flying tug dedicated to maneuvering to an optimal orbit to place secondary and hosted payloads. Spaceflight has manifested the SSPS on a Falcon 9 launch in 2013 and the SHERPA on launches in 2014 and 2015. This paper and presentation will outline the design details and payload capabilities of both the SSPS and SHERPA, with specific details on the payload interfaces, the available payload volume, predicted environments and expected launch integration flow