United Launch Alliance rideshare capabilities for providing low-cost access to space

United Launch Alliance (ULA) has a long history of providing launch services to high-value payloads for a variety of customers, including the US Department of Defense, the National Reconnaissance Office, NASA, and commercial customers. These missions have deployed a wide variety of capabilities into Earth orbit and beyond, such as navigation, communication, R&D, observation, and science, all which have provided us with a tremendous amount of knowledge about Earth and our solar system. The majority of these spacecraft has been launched as primary payloads, and used the full capability of the launch vehicle; yet there is a lower-cost alternative for achieving similar mission objectives: rideshare. Rideshare is the approach of sharing available launch vehicle performance and volume margins with two or more spacecraft that would otherwise go underutilized by the spacecraft community. This allows spacecraft customers the opportunity to get their spacecraft to orbit and beyond in an inexpensive and reliable manner. This concept has been regularly demonstrated since the 1960s, and these rideshare launches have proved that alternative ways to delivering important payloads to orbit in a cost-effective manner can be successfully achieved. Rideshare missions will become even more commonplace as newer launch service capabilities become available and the spacecraft customers choose to take advantage of them. The ULA family of launch vehicles - the Atlas V, the Delta II, and the Delta IV - all have rideshare capabilities that can be used by the community to launch payloads to orbit for a much lower price than a dedicated single-manifest mission. These capabilities support a wide range of spacecraft sizes, from the smallest Cubesats, to the largest dual-manifest payloads. This presentation will provide a technical overview of current and future rideshare capabilities available, including Delta II PPOD dispensers, the C-Adapter Platform (CAP), the Atlas V Aft Bulkhead Carrier (ABC), the EELV Secondary Payload Adapter (ESP A), the AQUILA, the eXternal Payload Carrier (XPC), and the Dual Spacecraft Systems (DSS-4 and DSS-5). Additionally, programmatic considerations for designing, manifesting, and integrating rideshare missions will be discussed.