Supersonic and Hypersonic Aerodynamic Extensions for OpenRocket: Technical Report

This technical report documents the OpenRocket Plus aerodynamic extensions implemented in the Java codebase. The work replaces legacy low-subsonic Barrowman assumptions with compressible atmosphere models, shock and expansion solvers, transonic blending, supersonic and hypersonic drag models, local-flow coupling for fin stability, static and dynamic stability corrections, high-angle-of-attack effects, and numerical hardening for six-degree-of-freedom (6-DOF) flight simulation. 

The framework is validated against a 25-flight ground-truth corpus (Mach 0.54 to 4.33) demonstrating a -0.38% mean signed apogee error (MAE of 4.74%), achieving parity with version-locked RASAero II predictions. Subsystem validations include nose wave drag models evaluated against NACA RM A52H28, fin lift characteristics against NASA TM X-653, and total vehicle drag profiles against the Army-Navy Basic Finner (ADA636861) benchmark corpus.