Continue the technology search. Reprioritize new technologies as required. As TD+D results (tests, data, etc) are obtained reevaluate and reprioritize as required. Be open to shifts in tactics.
Quick, efficient information exchange is required to accomodate the above. Consider an electronic forum (I-Net based?) to better enable the concurrent engineering process and the quick exchange of test results leading to conclusions and redirection.
Propulsion
Tripropellant is not desirable. The goal is not SSTO. It is affordable SSTO leading to commercialization.
Architecture and operability are key. Component development must be synergistic with systems and architecture, not an end in itself.
Structures
Robust, maintenance-free TPS is a top priority. Synergy with structures and operations a must. All current TPS technology candidates have some major operations deficiency which must be resolved successfully if SSTO is to be affordable.
Structures has key enabling technologies (AlLi, Composites, etc...) but must have more emphasis on robustness.
Avionics
VHM is key, but must be further defined. Diverse efforts must all be bought to work intensely together.
Architecture, Integrated GN+C, EMA's and power sources are key. STS for TD+D is definitely an option here and elsewhere if an efficient organizational structure can be determined for implementation.
Operations
Top RLV TD+D priority is to create a "way of doing business" which emphasizes concurrent engineering, operations input as key to affordability, efficient organizational structures with authority and responsibility at the lowest levels, and synergistic teamwork.
Operability must be included in system architectural concepts and be a key focus of all the disciplines.
Return to KSC Next Gen Site
Edgar Zapata, NASA Kennedy Space Center
Shuttle Process Engineering Directorate, Fluid Systems Division