Industry is being asked to propose concepts for reusable launch vehicles that could be used for a range of Defense Department requirements, from suborbital flights to heavy-lift missions.
The Reusable Booster System (RBS) request for information (RFI) issued by the U.S. Air Force Research Laboratory (AFRL) is a step toward the possible X-plane flight demonstration of a lower-cost, more-responsive launch vehicle combining a reusable first stage and expendable upper stage.
According to the solicitation, the RFI's objective "is to identify potential operational RBS concepts, including the family of expendable stage variants, and feasible system development approaches."
The plan is to conduct an integrated demonstration of technologies and processes culminating in a subscale X-plane vehicle that would fly by 2017-18 and take the concept to a technology readiness level of 6, ready to enter full-scale development.
AFRL has several ground-based experiments already under way involving structures, controls and systems for an operationally responsive launch vehicle. The work is focused on a reference concept for an unmanned vertical takeoff and horizontal landing reusable booster capable of turnaround in 24-48 hours and launch within 4-8 hours of a request.
After release of the expandable upper stage, the reusable booster would use its rocket engines to perform an autonomous post-staging maneuver, called "rocket-back," to orient and position the vehicle for a gliding landing near the launch site.
AFRL's reference concept includes an integral all-composite airframe and tank structure that carries both internal pressure and external flight loads. The concept vehicle is powered by pump-fed liquid-oxygen/hydrocarbon rocket engines.
While other vehicle concepts can be proposed in response to the RFI, the solicitation says "it is preferred for the flight demonstrator to use a previously developed main engine ... [with a] configuration similar to the expected operational system."
The RFI seeks a description of the vehicle concept, including ground systems and technology options; a concept of operations, including mission capabilities and costs; a development approach, including costs, risks and timelines; and potential synergies with other military and civil applications of the reusable booster and expendable stages.
In addition, the solicitation seeks ideas for demonstration projects in the areas of airframe, engines, control and health management, power, fluid, thermal and actuation subsystems, ground support and system integration.
Again, no time to comment. Too busy.