Low Cost Intermediate Stage for Affordable Nano/Micro Launch

NASA is extremely interested in developing small space launch capability. Small launchers are more sensitive to dry mass growth, more so then larger vehicles. Three stage launchers tend to be much more insensitive to Dry mass growth. The challenge then becomes how to meet strict cost targets when additional parts count increases. Use of Propane derived fuel helps reduce cost by allowing common bulkhead tanks w/o insulation. TGV proposes a DARPA funded Electrocycle Boost stage, and a NASA funded pressure fed Micro stage. upgrade NASA STTR funded nano-stage with 3,000 class pressure fed second stage ProPoly 50 engine. Goal: Provide flexible architecture to ensure success of TGV's 15,000 lb class first stage and 500 lbs class upper stage. Design and build engine in phase I. No avionics, strictly middle stage. Could be used for suborbital testing of small upper stages. Phase II: Test engine, build stage, fly.