Launch vehicles for low-cost planetary missions

Abstract

Delta has been synonymous with the launch of planetary missions for several decades. To make launches of all missions, including planetary missions, more affordable, launch vehicle evolution is necessary. The history of the Delta expendable launch vehicle has been one of constant evolution for almost 40 years and continues to evolve. Delta expendable launch vehicles include three basic variants: Delta II, Delta III, and Delta IV. Each vehicle is described and performance capabilities given for escape missions, GTO missions, and LEO missions. Injection accuracy for the Delta II has been better than 3 sigma. Actual injection accuracy performance figures for several planetary missions are presented. Data on launch environments are presented as well as the cleanliness environment available in the fairing and mobile service tower. Since many planetary missions depend on rather restricted launch windows, data are presented showing Delta's launch record within the launch window requirements. Delta has launched approximately 30 secondary missions over the past several years. Boeing is developing dual-payload capabilities for Delta II, Delta III, and Delta IV Heavy. Boeing also is evaluating auxiliary launch concepts for Delta IV. Over the past 40 years, Delta has significantly increased overall capability while reducing launch costs. Delta IV will continue this tradition with dramatic cost reductions while providing a more robust expendable launch vehicle.