Scratch Build.  SLS Block 2 scale.  This is in experimental stage w/Rock Sim 9.  Please feel free to download and tweak it.  Any suggestions, improvements or fixes are most welcome.

As it is now, the rocket requires at least two 24mm F engines, or three 24mm D engines.  I have attempted to provide a wide range of engine mix options.  There are five 24/18mm engine tubes and two 38/29/24mm engine tubes. Necking down to 18mm or 24mm of course requires an adapter.  A customizable mass object is located in the nose for adjusting CG.  The rocket simulates as excellent stability and low weather cocking.  

A full engine complement, using the lower impulse engines that match the non-adapted engine tubes, consisting of four Estes D11, two Contrail G300 SRB engines and one Aerotech D13W-10 with a 150g CG ballast yields 2150 feet altitude. I am working on improving the 24mm engine performance, but the drag profile for the build limits this.

Basic low flight with two Aerotech F12J-5 engines = 720 fft.

Basic low flight with three Estes D12-3 engines = 250 ft.