Hi Frank - thanks for your message. The cold, hard reality about my project is that this orbiter may not ever fly - think Enterprise over Atlantis. I have never built a rocket with 3D Molds and Carbon Fiber skin; I have never built anything with a retractable landing gear or doors. This was a concept model to get those skills in line. I also need a physical "twin" to go along with the "digital twin" for controlling this in recovery mode. It will take years to accomplish this goal, but I needed to start somewhere - and I know that these issues will take a while to iron out. Getting everything aligned and understanding how to support the shuttle on the External Tank, where the sensors need to go, how to attach and separate the orbiter from the ET are all hard problems getting solved along the way. As I move forward, getting models to weigh less will be a goal.